Seyed Ali Hosseini, Pierre Boivin, Dominique Thévenin, Ilya Karlin. Lattice Boltzmann methods for combustion applications. Progress in Energy and Combustion Science, 2024, 102, pp.101140. ⟨10.1016/j.pecs.2023.101140⟩. ⟨hal-04412786⟩ Plus de détails...
The lattice Boltzmann method, after close to thirty years of presence in computational fluid dynamics has turned into a versatile, efficient and quite popular numerical tool for fluid flow simulations. The lattice Boltzmann method owes its popularity in the past decade to its efficiency, low numerical dissipation and simplicity of its algorithm. Progress in recent years has opened the door for yet another very challenging area of application: Combustion simulations. Combustion is known to be a challenge for numerical tools due to, among many others, the large number of variables and scales both in time and space, leading to a stiff multi-scale problem. In the present work we present a comprehensive overview of models and strategies developed in the past years to model combustion with the lattice Boltzmann method and discuss some of the most recent applications, remaining challenges and prospects.
Seyed Ali Hosseini, Pierre Boivin, Dominique Thévenin, Ilya Karlin. Lattice Boltzmann methods for combustion applications. Progress in Energy and Combustion Science, 2024, 102, pp.101140. ⟨10.1016/j.pecs.2023.101140⟩. ⟨hal-04412786⟩
Journal: Progress in Energy and Combustion Science
Mostafa Taha, Song Zhao, Aymeric Lamorlette, Jean-Louis Consalvi, Pierre Boivin. Large eddy simulation of fire-induced flows using Lattice-Boltzmann methods. International Journal of Thermal Sciences, 2024, 197, pp.108801. ⟨10.1016/j.ijthermalsci.2023.108801⟩. ⟨hal-04338538⟩ Plus de détails...
Large-eddy simulations (LES) of the near-field region of large-scale fire plumes are performed for the first time with a pressure-based Lattice Boltzmann method (LBM) with low-Mach number approximation. Two scenarios are considered: the large-scale non-reactive helium plume and the 1 m methane pool fire, both investigated experimentally at Sandia. In the second scenario, a simplified modeling of the combustion and radiation processes is introduced involving a one-step irreversible reaction eddydissipation concept-based combustion model and a radiant fraction model, respectively. In both scenarios, a quantitative agreement is observed with the experimental data and model predictions are consistent with previouslypublished numerical studies. Our simulations demonstrate the computational efficiency of the proposed LBM solver to tackle fire-induced flows, suggesting that LBMs are a good alternative candidate for the modeling of fire-related problems.
Mostafa Taha, Song Zhao, Aymeric Lamorlette, Jean-Louis Consalvi, Pierre Boivin. Large eddy simulation of fire-induced flows using Lattice-Boltzmann methods. International Journal of Thermal Sciences, 2024, 197, pp.108801. ⟨10.1016/j.ijthermalsci.2023.108801⟩. ⟨hal-04338538⟩
Journal: International Journal of Thermal Sciences
A safe separation distance (SSD) needs to be considered during firefighting activities (fire suppression or people evacuation) against wildfires. The SSD is of critical interest for both humans and assets located in the wildland-urban interfaces (WUI). In most cases, the safety zone models and guidelines assume a flat terrain and only radiant heating. Nevertheless, injuries or damage do not result exclusively from radiant heating. Indeed, convection must be also considered as a significant contribution of heat transfer, particularly in the presence of the combined effects of sloping terrain and a high wind velocity. In this work, a critical case study is considered for the village of Sari-Solenzara in Corsica (France). This site location was selected by the operational staff since highintensity fire spread is likely to occur in the WUI during wind-blown conditions. This study was carried out for 4 m high shrubland, a sloping terrain of 12° and a wind speed of 16.6 m/s. The numerical simulations were performed using a fully physical fire model, namely, FireStar2D, to investigate a case of fire spreading, which is thought to be representative of most high wildfire risk situations in Corsica. This study is based on the evaluation of the total (radiative and convective) heat flux received by two types of targets (human bodies and buildings) located ahead of the fire front. The results obtained revealed that the radiation was the dominant heat transfer mode in the evaluation of the SSD. In addition, the predictions were consistent with the criterion established by the operational experts, which assumes that in Corsica, a minimum SSD of 50 m is required to keep an equipped firefighter without injury in a fuelbreak named ZAL. This numerical work also provides correlations relating the total heat flux to the SSD.
Jacky Fayad, Gilbert Accary, Frédéric Morandini, François-Joseph Chatelon, Lucile Rossi, et al.. Numerical Assessment of Safe Separation Distance in the Wildland-Urban Interfaces. Fire, 2023, 6 (209), ⟨10.3390/fire6050209⟩. ⟨hal-04101026⟩
G. Farag, P. Boivin, P. Sagaut. Linear interaction approximation for shock/disturbance interaction in a Noble–Abel stiffened gas. Shock Waves, 2023, ⟨10.1007/s00193-023-01131-8⟩. ⟨hal-04097657⟩ Plus de détails...
When departure from the ideal gas equation of state is considered, the Noble-Abel stiffened gas model is an appealing and versatile candidate due to its simple form. The Linear Interaction Approximation formalism is extended to consider non-ideal gas effects introduced by this equation of state. Kovásznay decomposition and adequate definition of the energy of disturbances are provided in the context of this equation of state. Changes with respect to ideal gas are investigated on transfer functions, critical angle and compression factor. Those differences yield concrete effects on the damping and transfer of fluctuations across shock waves. Those changes are further illustrated by considering the interaction of an entropy spot with a Mach 3 stationary shock wave.
G. Farag, P. Boivin, P. Sagaut. Linear interaction approximation for shock/disturbance interaction in a Noble–Abel stiffened gas. Shock Waves, 2023, ⟨10.1007/s00193-023-01131-8⟩. ⟨hal-04097657⟩
Song Zhao, Karthik Bhairapurada, Muhammad Tayyab, Renaud Mercier, Pierre Boivin. Lattice-Boltzmann modelling of the quiet and unstable PRECCINSTA burner modes. Computers and Fluids, 2023, pp.105898. ⟨10.1016/j.compfluid.2023.105898⟩. ⟨hal-04085625⟩ Plus de détails...
Song Zhao, Karthik Bhairapurada, Muhammad Tayyab, Renaud Mercier, Pierre Boivin. Lattice-Boltzmann modelling of the quiet and unstable PRECCINSTA burner modes. Computers and Fluids, 2023, pp.105898. ⟨10.1016/j.compfluid.2023.105898⟩. ⟨hal-04085625⟩
Jacky Fayad, Morandini Frédéric, Gilbert Accary, François-Joseph Chatelon, Clément Wandon, et al.. A Study of Two High Intensity Fires across Corsican Shrubland. Atmosphere, 2023, ⟨10.3390/atmos14030473⟩. ⟨hal-04007587⟩ Plus de détails...
This paper reports two experimental fires conducted at field-scale in Corsica, across a particular mountain shrubland. The orientation of the experimental plots was chosen in such a way that the wind was aligned along the main slope direction in order to obtain a high intensity fire. The first objective was to study the high intensity fire behavior by evaluating the propagation conditions related to its speed and intensity, as well as the geometry of the fire front and its impact on different targets. Therefore, an experimental protocol was designed to determine the properties of the fire spread using UAV cameras and its impact using heat flux gauges. Another objective was to study these experiments numerically using a fully physical fire model, namely FireStar3D. Numerical results concerning the fire dynamics, particularly the ROS, were also compared to other predictions of the FireStar2D model. The comparison with experimental measurements showed the robustness of the 3D approach with a maximum difference of 5.2% for the head fire ROS. The fire intensities obtained revealed that these experiments are representative of high intensity fires, which are very difficult to control in the case of real wildfires. Other parameters investigated numerically (flame geometry and heat fluxes) were also in fairly good agreement with the experimental measurements and confirm the capacity of FireStar3D to predict surface fires of high intensity.
Jacky Fayad, Morandini Frédéric, Gilbert Accary, François-Joseph Chatelon, Clément Wandon, et al.. A Study of Two High Intensity Fires across Corsican Shrubland. Atmosphere, 2023, ⟨10.3390/atmos14030473⟩. ⟨hal-04007587⟩
Marc Le Boursicaud, Song Zhao, Jean-Louis Consalvi, Pierre Boivin. An improved passive scalar model for hydrogen hazardous ignition prediction. Combustion and Flame, 2023, 256, pp.112938. ⟨10.1016/j.combustflame.2023.112938⟩. ⟨hal-04169558⟩ Plus de détails...
With an increasing interest in hydrogen as an alternative fuel for transportation, there is a need to develop tools for the prediction of ignition events. A cost-effective passive scalar formulation has been recently developed to predict hydrogen auto-ignition. A single scalar advection-diffusion-reaction equation is used to reproduce the chain-branched ignition process, where the scalar represents the radical pool responsible of ignition (H, O, OH, HO2 , H2O2). The scalar reaction rate is analytically deduced from the Jacobian matrix associated to hydrogen ignition chemistry. This method was found to reproduce with good accuracy the ignition delays obtained by detailed chemistry for temperature where the branching is the leading process. For temperature close or below the crossover temperature, where other phenomenon such as the thermal runaway are important, the scalar approach fails to predict correctly ignition events. Thus, an extension of the scalar source term formulation is proposed to extend its validity over the entire temperature range. In addition, a simple way to approximate the diffusion properties of the scalar is introduced: the radical pool composition may vary drastically, with molecules having very different diffusion properties (e.g. H and HO2). The complete modified framework is presented and its capability is assessed in canonical scenarios and more complex simulations relevant to hydrogen safety.
Marc Le Boursicaud, Song Zhao, Jean-Louis Consalvi, Pierre Boivin. An improved passive scalar model for hydrogen hazardous ignition prediction. Combustion and Flame, 2023, 256, pp.112938. ⟨10.1016/j.combustflame.2023.112938⟩. ⟨hal-04169558⟩
Gauthier Wissocq, Said Taileb, Song Zhao, Pierre Boivin. A hybrid lattice Boltzmann method for gaseous detonations. Journal of Computational Physics, 2023, 494, pp.112525. ⟨10.1016/j.jcp.2023.112525⟩. ⟨hal-04244340⟩ Plus de détails...
This article is dedicated to the construction of a robust and accurate numerical scheme based on the lattice Boltzmann method (LBM) for simulations of gaseous detonations. This objective is achieved through careful construction of a fully conservative hybrid lattice Boltzmann scheme tailored for multi-species reactive flows. The core concept is to retain LBM low dissipation properties for acoustic and vortical modes by using the collide and stream algorithm for the particle distribution function, while transporting entropic and species modes via a specifically designed finite-volume scheme. The proposed method is first evaluated on common academic cases, demonstrating its ability to accurately simulate multi-species compressible and reactive flows with discontinuities: the convection of inert species, a Sod shock tube with two ideal gases and a steady one-dimensional inviscid detonation wave. Subsequently, the potential of this novel approach is demonstrated in one- and two-dimensional inviscid unsteady gaseous detonations, highlighting its ability to accurately recover detonation structures and associated instabilities for high activation energies. To the authors' knowledge, this study is the first successful simulation of detonation cellular structures capitalizing on the LBM collide and stream algorithm.
Gauthier Wissocq, Said Taileb, Song Zhao, Pierre Boivin. A hybrid lattice Boltzmann method for gaseous detonations. Journal of Computational Physics, 2023, 494, pp.112525. ⟨10.1016/j.jcp.2023.112525⟩. ⟨hal-04244340⟩
Benoît Péden, Julien Carmona, Pierre Boivin, Schmitt Thomas, Bénédicte Cuenot, et al.. Numerical assessment of Diffuse-Interface method for air-assisted liquid sheet simulation. Computers and Fluids, 2023, 266, pp.106022. ⟨10.1016/j.compfluid.2023.106022⟩. ⟨hal-04244347⟩ Plus de détails...
This study presents the implementation and validation of a second-order accurate solver for the 4-equation multi-fluid method in a cell-vertex context, to handle aeronautical air-assisted liquid sheet configurations. Validations include one and two-dimensional shock tube problems, Laplace tests, droplets oscillations, and a two-dimensional configuration reminiscent of an aeronautical airblast injector. Promising results are obtained in the last case, especially when the pressure is increased and the characteristic flow times decreased, a trend observed in recent aeronautical developments, but not necessary in classical academical benchmarks. Being fully compatible of the reactive flow formulation of the cell-vertex solver AVBP, this study paves the way to future monolithic simulations of airblast injectors for aeronautical combustion chambers, including both the multi-phase and the reactive regions.
Benoît Péden, Julien Carmona, Pierre Boivin, Schmitt Thomas, Bénédicte Cuenot, et al.. Numerical assessment of Diffuse-Interface method for air-assisted liquid sheet simulation. Computers and Fluids, 2023, 266, pp.106022. ⟨10.1016/j.compfluid.2023.106022⟩. ⟨hal-04244347⟩
Pierre Boivin, Marc Le Boursicaud, Alejandro Millán-Merino, Said Taileb, Josué Melguizo-Gavilanes, et al.. Hydrogen ignition and safety. Efstathios-Al. Tingas. Hydrogen for Future Thermal Engines, Springer International Publishing, pp.161-236, 2023, Green Energy and Technology, 978-3-031-28411-3. ⟨10.1007/978-3-031-28412-0_5⟩. ⟨hal-04244414⟩ Plus de détails...
This chapter provides an overview of H 2 ignition and safety-related questions, to be addressed in the development of future H 2 thermal engines. Basics of H 2 ignition phenomena are covered in the first part, including the well-known branchedchain oxidation reactions described by Semenov & Hinshelwood, as well as useful analytical derivations of induction delay times. The second part provides an overview of classical canonical limit problems, including the explosion-limit (,) diagram, the propagation limits of both deflagrations and detonations, and shock-induced or thermal-induced ignitions. The two remaining parts address two opposite but complementary questions: how to ignite a H 2 engine, and how to prevent hazardous H 2 ignition. In the former, a list of available technologies is offered, while in the latter, simplified models are presented to predict ignition hazards from cold-flow numerical simulations.
Pierre Boivin, Marc Le Boursicaud, Alejandro Millán-Merino, Said Taileb, Josué Melguizo-Gavilanes, et al.. Hydrogen ignition and safety. Efstathios-Al. Tingas. Hydrogen for Future Thermal Engines, Springer International Publishing, pp.161-236, 2023, Green Energy and Technology, 978-3-031-28411-3. ⟨10.1007/978-3-031-28412-0_5⟩. ⟨hal-04244414⟩
Said Taileb, Alejandro Millán-Merino, Song Zhao, Pierre Boivin. Lattice-Boltzmann modeling of lifted hydrogen jet flames: A new model for hazardous ignition prediction. Combustion and Flame, 2022, 245, pp.112317. ⟨10.1016/j.combustflame.2022.112317⟩. ⟨hal-03796395⟩ Plus de détails...
This numerical study deals with the hazardous ignition of a jet flame in a vitiated co-flow. A novel formulation, based on a passive scalar variable, will be presented to predict hydrogen auto-ignition events. The model, derived from the theoretical analysis of the Jacobian, correctly describes the appearance and absence of auto-ignition in complex configurations based on initial thermodynamic and mixture conditions. No chemical reaction and species equations are required to perform the simulations. Results of Lattice Boltzmann Methods (LBM) simulations of a 3D H 2 /N 2 Cabra flame will be presented using a detailed H 2-Air mechanism. Validation against experimental and numerical results will be provided for the lift-off (distance to auto-ignition). The passive scalar predictions are successfully compared with the reactive simulations. The results show a potential extension of this model to an extensive spectrum of hydrogen safety and large-scale turbulent combustion applications.
Said Taileb, Alejandro Millán-Merino, Song Zhao, Pierre Boivin. Lattice-Boltzmann modeling of lifted hydrogen jet flames: A new model for hazardous ignition prediction. Combustion and Flame, 2022, 245, pp.112317. ⟨10.1016/j.combustflame.2022.112317⟩. ⟨hal-03796395⟩
Alejandro Millán-Merino, Said Taileb, Pierre Boivin. A new method for systematic 1-step chemistry reduction applied to hydrocarbon combustion. Proceedings of the Combustion Institute, 2022, ⟨10.1016/j.proci.2022.08.052⟩. ⟨hal-03825847⟩ Plus de détails...
We propose a new single-step mechanism for the combustion of arbitrary hydrocarbons and alcohols. Unlike most single-step models, no tabulation is required, as the method builds upon a new analytical description of the thermochemical equilibrium of fuel-oxidizer mixtures including dihydrogen and carbon monoxide-two species usually discarded in one-step descriptions-yielding correct adiabatic temperature. The single-step chemistry includes varying stoichiometric coefficients, ensuring a convergence towards thermochemical equilibrium regardless of the local state. The reaction rate is then carefully adjusted to reproduce accurately premixed flames. To tackle ignition simultaneously, an additional passive scalar advection-diffusion-reaction equation is introduced, with a rate fitted on ignition delays. The scalar then serves as an efficiency to modify the single-step reaction rate in autoignition configurations. The obtained scheme is then validated for a wide range of equivalence ratios on homogeneous reactors, premixed flames, a triple flame, and a counterflow diffusion flame. The new analytical thermochemical equilibrium formulation may also serve in speeding up infinitely fast chemistry calculations.
Alejandro Millán-Merino, Said Taileb, Pierre Boivin. A new method for systematic 1-step chemistry reduction applied to hydrocarbon combustion. Proceedings of the Combustion Institute, 2022, ⟨10.1016/j.proci.2022.08.052⟩. ⟨hal-03825847⟩
Pierre Boivin, Yves Connier, Bertrand Dousteyssier, Didier Miallier, Élise Nectoux, et al.. Protohistoire de la moyenne montagne auvergnate : le cas du versant oriental du Cézallier à l’âge du Bronze et au Ier âge du Fer, premier état des lieux. Frédéric Surmely. Archéologie en milieu de montagne dans la région Auvergne-Rhône-Alpes : Actes de la table ronde de Clermont-Ferrand (6 décembre 2019), Presses universitaires Blaise Pascal, pp.137-160, 2022, Terra Mater, 9782383770046. ⟨hal-04123826⟩ Plus de détails...
Pierre Boivin, Yves Connier, Bertrand Dousteyssier, Didier Miallier, Élise Nectoux, et al.. Protohistoire de la moyenne montagne auvergnate : le cas du versant oriental du Cézallier à l’âge du Bronze et au Ier âge du Fer, premier état des lieux. Frédéric Surmely. Archéologie en milieu de montagne dans la région Auvergne-Rhône-Alpes : Actes de la table ronde de Clermont-Ferrand (6 décembre 2019), Presses universitaires Blaise Pascal, pp.137-160, 2022, Terra Mater, 9782383770046. ⟨hal-04123826⟩
Adil Mouahid, Pierre Boivin, Suzanne Diaw, Elisabeth Badens. Widom and extrema lines as criteria for optimizing operating conditions in supercritical processes. Journal of Supercritical Fluids, 2022, 186, pp.105587. ⟨10.1016/j.supflu.2022.105587⟩. ⟨hal-03797377⟩ Plus de détails...
Adil Mouahid, Pierre Boivin, Suzanne Diaw, Elisabeth Badens. Widom and extrema lines as criteria for optimizing operating conditions in supercritical processes. Journal of Supercritical Fluids, 2022, 186, pp.105587. ⟨10.1016/j.supflu.2022.105587⟩. ⟨hal-03797377⟩
Mostafa Taha, Song Zhao, Aymeric Lamorlette, Jean-Louis Consalvi, Pierre Boivin. Lattice-Boltzmann modeling of buoyancy-driven turbulent flows. Physics of Fluids, 2022, ⟨10.1063/5.0088409⟩. ⟨hal-03661928⟩ Plus de détails...
The pressure-based hybrid lattice-Boltzmann method presented by Farag & al (Phys. Fluids 2020) is assessed for the simulation of buoyancy driven flows. The model is first validated on Rayleigh-Benard and Rayleigh-Taylor two-dimensional cases. A large-eddy simulation of a turbulent forced plume is then carried out, and results are validated against experiments. A good overall agreement is obtained, both for mean and fluctuations quantities, as well as global entertainment. The self-similarity character of the plume in the far-field is also recovered.
Mostafa Taha, Song Zhao, Aymeric Lamorlette, Jean-Louis Consalvi, Pierre Boivin. Lattice-Boltzmann modeling of buoyancy-driven turbulent flows. Physics of Fluids, 2022, ⟨10.1063/5.0088409⟩. ⟨hal-03661928⟩
Guanxiong Wang, Song Zhao, Pierre Boivin, Eric Serre, Pierre Sagaut. A new hybrid lattice-Boltzmann method for thermal flow simulations in low-Mach number approximation. Physics of Fluids, 2022, 34 (4), pp.046114. ⟨10.1063/5.0091517⟩. ⟨hal-03796386⟩ Plus de détails...
A new low-Mach algorithm for the thermal lattice Boltzmann method (LBM) is proposed aiming at reducing the computational cost of thermal flow simulations in the low Mach number limit. The well-known low Mach number approximation is adopted to accelerate the simulations by enlarging the time step through re-scaling the psuedoacoustic speed to the same order of the fluid motion velocity. This specific process is inspired by the similarity between the artificial compressibility method and the isothermal LBM and is further extended to its thermal counterpart. It must be emphasized that such low-Mach acceleration strategy is in a general form, thus can be easily applied to other compressible LB methods. The present method overcomes the drawback of the classical pressure gradient scaling method due to the pressure gradient changing. The new algorithm is validated by various well-documented academic test cases in laminar [one dimensional gravity column, 2D (two dimensional) rising thermal bubble, and 2D differentially heated square cavity] and turbulent [3D (three dimensional) Taylor–Green vortex and 3D heated cylinder] regimes. All the results show excellent agreement with the reference data and high computational efficiency.
Guanxiong Wang, Song Zhao, Pierre Boivin, Eric Serre, Pierre Sagaut. A new hybrid lattice-Boltzmann method for thermal flow simulations in low-Mach number approximation. Physics of Fluids, 2022, 34 (4), pp.046114. ⟨10.1063/5.0091517⟩. ⟨hal-03796386⟩
Karthik Bhairapurada, Bruno Denet, Pierre Boivin. A Lattice-Boltzmann study of premixed flames thermo-acoustic instabilities. Combustion and Flame, 2022, 240, pp.112049. ⟨hal-03582162⟩ Plus de détails...
We present possibly for the first time Lattice-Boltzmann numerical simulations of thermo-acoustic instabilities of premixed flames. We study flames interacting with an imposed acoustic field where flames submitted to a parametric instability can be observed, as well as plane flames re-stabilized by the acoustic forcing. Self-induced thermo-acoustic oscillations of flames propagating in narrow channels are also studied, indicating an unexpected dependency with the channel width. For both excited and self-excited flames, results confirm that Lattice-Boltzmann method can capture the complex coupling between flame dynamics and acoustics.
Karthik Bhairapurada, Bruno Denet, Pierre Boivin. A Lattice-Boltzmann study of premixed flames thermo-acoustic instabilities. Combustion and Flame, 2022, 240, pp.112049. ⟨hal-03582162⟩
François Joseph Chatelon, Jacques Henri Balbi, Miguel Cruz, Dominique Morvan, Jean Louis Rossi, et al.. Extending the Balbi fire spread Model for field scale conditions: the case of shrubland fires. International Journal of Wildland Fire, 2022, 31 (2), pp.176-192. ⟨10.1071/WF21082⟩. ⟨hal-04064057⟩ Plus de détails...
The 'Balbi model' is a simplified rate of fire spread model aimed at providing fast and accurate simulations for fire spread that can be used by fire managers under operational conditions. This model describes the steady-state spread rate of surface fires by accounting for both radiation and convection heat transfer processes. In the present work the original Balbi model developed for laboratory conditions is improved with changes that address specificities of outdoor fires, such as fuel complexes with a mix of live and dead materials, a larger scale and an open environment. The model is calibrated against a small training dataset (n=25) of shrubland fires conducted in Turkey. A sensitivity analysis of model output is presented and its predictive capacity against a larger independent dataset of experimental fires in shrubland fuels
François Joseph Chatelon, Jacques Henri Balbi, Miguel Cruz, Dominique Morvan, Jean Louis Rossi, et al.. Extending the Balbi fire spread Model for field scale conditions: the case of shrubland fires. International Journal of Wildland Fire, 2022, 31 (2), pp.176-192. ⟨10.1071/WF21082⟩. ⟨hal-04064057⟩
Housseyn Smahi, Djilali Ameur, Joanna Dib, Isabelle Raspo. On the modeling and simulation of coupled adsorption and thermosolutal convection in supercritical carbon dioxide. Journal of Engineering and Applied Science, 2022, 69 (1), pp.5. ⟨10.1186/s44147-021-00054-4⟩. ⟨hal-03567395⟩ Plus de détails...
Abstract In this paper, we present a numerical study along with an exhaustive adsorption investigation in a binary dilute mixture model nearby the solvent’s critical point in a configuration relevant for soil remediation. By means of this model, mass and heat transfer efficiency were qualitatively and quantitatively discussed through this work. The convergence of the solution was evaluated on the values of the Nusselt and Sherwood numbers. The results reveal intense convection expanding into the cavity close to the critical point, thus enabling homogeneous adsorption of the solute. Moreover, the mass fraction perturbation isolines exhibit the existence, along the adsorbent plate, of a thin boundary layer which becomes thinner when approaching the critical point.
Housseyn Smahi, Djilali Ameur, Joanna Dib, Isabelle Raspo. On the modeling and simulation of coupled adsorption and thermosolutal convection in supercritical carbon dioxide. Journal of Engineering and Applied Science, 2022, 69 (1), pp.5. ⟨10.1186/s44147-021-00054-4⟩. ⟨hal-03567395⟩
Journal: Journal of Engineering and Applied Science
Gilbert Accary, Jacky Fayad, François-Joseph Chatelon, Nicolas Frangieh, Carmen Awad, et al.. Simulation of induced-wind-dominated fire on sloping terrain. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.375-380, 2022, ⟨10.14195/978-989-26-2298-9_59⟩. ⟨hal-03875345⟩ Plus de détails...
Using the fully physical model FireStar3D, a numerical simulation of an eruptive fire was carried out for a grassland on a slopping terrain (30° inclination) and a 10 m-open wind speed of 2 m/s. To reproduce the behaviour of a quasi-infinite fire front, periodic conditions were considered in the fireline direction. The simulation highlights the role played by the additional wind induced by the fire (that reaches about 5.8 m/s at 10 m above ground) and its feedback action on fire behaviour. This interaction results in the transition of the fire behaviour from a plume-dominated fire to a wind-dominated fire, and this goes along with a substantial increase of the rate of spread (from 0.454 m/s to 0.714 m/s) and of the fireline heat release rate (from 4.8 MW/m to 14 MW/m). The fire regime was characterized by Byram’s convection number, based on the effective crosswind speed, that drops from 46.8 to about 3.8 once fire-induced wind takes effect on fire behaviour.
Gilbert Accary, Jacky Fayad, François-Joseph Chatelon, Nicolas Frangieh, Carmen Awad, et al.. Simulation of induced-wind-dominated fire on sloping terrain. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.375-380, 2022, ⟨10.14195/978-989-26-2298-9_59⟩. ⟨hal-03875345⟩
Dominique Morvan, Gilbert Accary, Sofiane Meradji, Nicolas Frangieh. Fifty years of progress in wildland fire modelling: from empirical to fully physical CFD models. Comptes Rendus. Mécanique, 2022, 350 (S1), pp.1-9. ⟨10.5802/crmeca.133⟩. ⟨hal-04063901⟩ Plus de détails...
The aim of this short review is to present the progress made in wildland fire modelling during the last 50 years and the intellectual track followed by wildland fires models, from fully empirical models in the 60s, to semi-empirical ones in the 70s, to fully physical models at the end of the 90s. During the last period, the large diffusion of HPC methods substantially contributed to the development of multiphase formulations applied to wildland fire modelling. Many studies have particularly focused on the effects of various parameters (vegetation, topography, atmosphere) affecting the behaviour of a fire front propagating through a forest fuel layer.
Dominique Morvan, Gilbert Accary, Sofiane Meradji, Nicolas Frangieh. Fifty years of progress in wildland fire modelling: from empirical to fully physical CFD models. Comptes Rendus. Mécanique, 2022, 350 (S1), pp.1-9. ⟨10.5802/crmeca.133⟩. ⟨hal-04063901⟩
Alejandro Millán-Merino, Said Taileb, Pierre Boivin. A new method for systematic 1-step chemistry reduction applied to hydrocarbon combustion. Proceedings of the Combustion Institute, In press, ⟨10.1016/j.proci.2022.08.052⟩. ⟨hal-04063894⟩ Plus de détails...
We propose a new single-step mechanism for the combustion of arbitrary hydrocarbons and alcohols. Unlike most single-step models, no tabulation is required, as the method builds upon a new analytical description of the thermochemical equilibrium of fuel-oxidizer mixtures including dihydrogen and carbon monoxide-two species usually discarded in one-step descriptions-yielding correct adiabatic temperature. The single-step chemistry includes varying stoichiometric coefficients, ensuring a convergence towards thermochemical equilibrium regardless of the local state. The reaction rate is then carefully adjusted to reproduce accurately premixed flames. To tackle ignition simultaneously, an additional passive scalar advection-diffusion-reaction equation is introduced, with a rate fitted on ignition delays. The scalar then serves as an efficiency to modify the single-step reaction rate in autoignition configurations. The obtained scheme is then validated for a wide range of equivalence ratios on homogeneous reactors, premixed flames, a triple flame, and a counterflow diffusion flame. The new analytical thermochemical equilibrium formulation may also serve in speeding up infinitely fast chemistry calculations.
Alejandro Millán-Merino, Said Taileb, Pierre Boivin. A new method for systematic 1-step chemistry reduction applied to hydrocarbon combustion. Proceedings of the Combustion Institute, In press, ⟨10.1016/j.proci.2022.08.052⟩. ⟨hal-04063894⟩
Carmen Awad, Jacky Fayad, Nicolas Frangieh, Frédéric Morandini, Jean Louis Rossi, et al.. Impact of the bulk density on fire spread through a homogenous vegetation layer. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.1657-1664, 2022, ⟨10.14195/978-989-26-2298-9_254⟩. ⟨hal-03875325⟩ Plus de détails...
The bulk density as definition represents the ratio between the packing ratio and the density of the vegetation. Therefore, it is directly related to the fuel load, the height and to the porosity of the vegetation. In fact, the bulk density plays an important role in fire propagation and behavior. Due to its dependence on the fuel porosity, the bulk density influences heat transfers inside the fuel bed, so, it can affect directly the rate of spread. Or, the bulk density influences also the fire intensity and flame characteristics (residence time, height and depth) due to its dependence of the fuel load and fuel bed height. However, despite the important influence of the bulk density on fire propagation, the literature does not clarify its impact on fire behavior, different points of view can be exanimated. So, the aim of this study is to investigate the role played by the bulk density upon both propagation parameters and heat transfer of a surface fire through a homogeneous vegetation layer. Investigations were conducted numerically using “FireStar2Dâ€, a complete physical model based on multiphase formulation. Also, experimentally, tests were constructed at the university of Corsica at laboratory scale under no wind and no slope condition. In order to study the elementary effect of the bulk density on fire behavior, three different cases were evaluated: (a) variable fuel load with a constant bulk density, (b) variable fuel load and variable bulk density, (c) variable bulk density with a constant fuel load. Case (a) was only studied numerically, the obtained results are in agreement with the literature: the rate of spread increases with the fuel load until a specific value where the ROS becomes independent of it. Case (b) was evaluated numerically and experimentally using a fix fuel bed height. The numerical and the experimental results showed that the ROS is barely affected by both fuel load and bulk density. Finally, the results of the last case, with a constant fuel load, showed numerically the same tendency proposed by Rothermel: the rate of spread reaches a maximum value at an optimal packing ratio that depends of the surface-volume ratio of the vegetation. Or, experimentally the ROS decreases with the increase of the bulk density. Different variables such as the optical thickness, the fire intensity, the residence time, the radiation and convection heat fluxes have been analyzed.
Carmen Awad, Jacky Fayad, Nicolas Frangieh, Frédéric Morandini, Jean Louis Rossi, et al.. Impact of the bulk density on fire spread through a homogenous vegetation layer. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.1657-1664, 2022, ⟨10.14195/978-989-26-2298-9_254⟩. ⟨hal-03875325⟩
Nicolas Godinaud, Pierre Boivin, Pierre Freton, Jean-Jacques Gonzalez, Frédéric Camy-Peyret. Development of a new OpenFOAM solver for plasma cutting modelling. Computers and Fluids, 2022, ⟨10.1016/j.compfluid.2022.105479⟩. ⟨hal-03661919⟩ Plus de détails...
A new OpenFOAM solver is presented, for the simulation of plasma cutting torches. The mathematical model that is introduced is based on the compressible Navier-Stokes equations coupled via source terms to the electric current conservation equation. Due to the conservative and hyperbolic nature of the model, a Godunov-type scheme is used for the first time in the context of plasma cutting simulation. The numerical method consists of a second-order Total Variation Diminishing (TVD) integration with flux Harten-Lax-van Leer-Contact (HLLC) Riemann solver for the flow conservation equations, coupled with a Laplace solver for the current conservation equation. An efficient formulation for the equation of state, accurately taking into account the plasma properties, is also presented. The solver is validated through a set of canonical test cases (shock tubes and 2D Riemann problems) and it is used to simulate a three-dimensional plasma cutting torch. Good agreement is found with the literature, with an improvement in the ability to deal with the shocks occurring during plasma cutting.
Nicolas Godinaud, Pierre Boivin, Pierre Freton, Jean-Jacques Gonzalez, Frédéric Camy-Peyret. Development of a new OpenFOAM solver for plasma cutting modelling. Computers and Fluids, 2022, ⟨10.1016/j.compfluid.2022.105479⟩. ⟨hal-03661919⟩
Jacky Fayad, Lucile Rossi, Nicolas Frangieh, Carmen Awad, Gilbert Accary, et al.. Numerical study of high intensity experimental field fires across Corsican shrubland vegetation. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.1725-1732, 2022, ⟨10.14195/978-989-26-2298-9_266⟩. ⟨hal-03875178⟩ Plus de détails...
Jacky Fayad, Lucile Rossi, Nicolas Frangieh, Carmen Awad, Gilbert Accary, et al.. Numerical study of high intensity experimental field fires across Corsican shrubland vegetation. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.1725-1732, 2022, ⟨10.14195/978-989-26-2298-9_266⟩. ⟨hal-03875178⟩
Guillaume Martin, Sébastien Gaime, Pierre Boivin, Bertrand Dousteyssier, Didier Miallier, et al.. Production et diffusion des sarcophages en trachyte de la chaîne des Puys (Massif central, France) au premier Moyen Âge (Ve-IXe s.). Yves Henigfeld; Édith Peytremann. Un monde en mouvement : la circulation des personnes, des biens et des idées à l’époque mérovingienne (Ve-VIIIe siècle), AFAM, pp.241-258, 2022, Mémoires de l’Association française d’Archéologie mérovingienne ; Tome XXXVII, 979-10-90282-02-5. ⟨hal-04128988⟩ Plus de détails...
Guillaume Martin, Sébastien Gaime, Pierre Boivin, Bertrand Dousteyssier, Didier Miallier, et al.. Production et diffusion des sarcophages en trachyte de la chaîne des Puys (Massif central, France) au premier Moyen Âge (Ve-IXe s.). Yves Henigfeld; Édith Peytremann. Un monde en mouvement : la circulation des personnes, des biens et des idées à l’époque mérovingienne (Ve-VIIIe siècle), AFAM, pp.241-258, 2022, Mémoires de l’Association française d’Archéologie mérovingienne ; Tome XXXVII, 979-10-90282-02-5. ⟨hal-04128988⟩
Nicolas Frangieh, Gilbert Accary, Jean-Louis Rossi, Dominique Morvan, François-Joseph Chatelon, et al.. Fuelbreaks design: from CFD modelling to operational tools. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.222-226, 2022, ⟨10.14195/978-989-26-2298-9_36⟩. ⟨hal-03875340⟩ Plus de détails...
Dimensioning a fuelbreak remains always a challenging problem. For a long time, this problem was tackled using an empirical approach from the experience of operational users such as the fire fighters and the foresters. During the last decades, new approaches coming from fire safety engineering have completed the set of tools adapted to study this problem. These tools are all based on physical considerations, more or- less sophisticated. The simplest ones, consist in assimilating the flame as a radiant panel, calculating the distribution of radiant heat flux as a function of the distance separating the flame to a potential target and defining at what distance this heat flux reached a critical threshold level susceptible to produce damages on this target (pain for people or ignition for materials). The most complex ones, consist in solving the conservation equations (mass, momentum, energy ...) governing the behaviour of complex coupled problem formed by the vegetation, the flame front and the surrounding atmosphere. This new generation of engineering tool, based on CFD approach allows to directly predict the behaviour of a fire front propagating toward a fuelbreak, in order to evaluate its efficiency as a function of the amount of surface fuel (grass, shrubs) removed to reduce locally the fuel load and therefore the intensity of an incoming fire. These two approaches are fully complementary, only the first one has the potentiality to be spread operationally on the field, whereas the second one can contribute to improve the first one and to study with more detail some very sensitive situations such as those encountered in the wildland urban interface (WUI). The main part of this study concerns numerical simulations of the propagation of a fire front through a homogeneous vegetation layer (a grassland) in the vicinity of a fuelbreak represented by a band more or less wide inside which all the fuel was removed. The simulations were performed using a fully physical wildfire model (FIRESTAR3D), three variable parameters were considered in this study: the 1m open wind speed (U1 ranged between 3 and 10 m/s), the fuel height (HFuel ranged between 0.25 and 1m) and the fuelbreak width (LFB). With these conditions, the simulations covered a large range of values of the Byram’s convective number NC (0.3 < NC < 60) in order to explore wind as well driven fires (NC < 2) and plume dominated fires (NC > 10). The 72 simulations carried out in this study have been classified in three categories: 1/ Propagation (if the fire has crossed the fuelbreak with a propagation after); 2/ Overshooting or Marginal (if the fire has crossed the fuelbreak without a propagation after); 3/ No-propagation (if the fuelbreak has stopped the fire). The main objective of this study was to determine the optimal fuelbreak width LFBx separating between the Propagation and the No-propagation regimes, in order to generalize the conclusion, the results have been presented in dimensionless form (similitude theory) in representing as an example the ratio LFBx/HFuel versus the Byram’s convective number NC.
Nicolas Frangieh, Gilbert Accary, Jean-Louis Rossi, Dominique Morvan, François-Joseph Chatelon, et al.. Fuelbreaks design: from CFD modelling to operational tools. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.222-226, 2022, ⟨10.14195/978-989-26-2298-9_36⟩. ⟨hal-03875340⟩
Guanxiong Wang, Song Zhao, Pierre Boivin, Eric Serre, Pierre Sagaut. A new hybrid Lattice-Boltzmann method for thermal flow simulations in low-Mach number approximation. Physics of Fluids, 2022, Physics of fluids, 34 (046114). ⟨hal-03636905⟩ Plus de détails...
Guanxiong Wang, Song Zhao, Pierre Boivin, Eric Serre, Pierre Sagaut. A new hybrid Lattice-Boltzmann method for thermal flow simulations in low-Mach number approximation. Physics of Fluids, 2022, Physics of fluids, 34 (046114). ⟨hal-03636905⟩
Jacky Fayad, Lucile Rossi, Nicolas Frangieh, Carmen Awad, Gilbert Accary, et al.. Numerical study of an experimental high-intensity prescribed fire across Corsican Genista salzmannii vegetation. Fire Safety Journal, 2022, 131, pp.103600. ⟨10.1016/j.firesaf.2022.103600⟩. ⟨hal-04063905⟩ Plus de détails...
This paper reported a high intensity experimental fire conducted during a field-scale experiment on a steep sloped terrain (28°) as part of a winter prescribed burns campaign managed by the local firefighter service in the northwestern region of Corsica. The rate of spread (ROS) of fire, measured using UAV cameras (thermal and visible), was evaluated at 0.45 m/s. The experiment was numerically reproduced using a completely physical 2D model, namely FireStar2D, and the comparison with the experimental measurements mainly concerned the fire ROS and the heat fluxes received by three distant targets placed at the end of the plot. The results analysis shows that the considered fire has a wind-driven regime of propagation with a fire intensity higher than 7 MW/m. The numerical results are in fairly good agreement with the experimental measurements, within 11% difference for the ROS and 5% for the heat fluxes, validating consequently the relevance of the numerical approach to tackle such high-intensity wildfires. Despite the unfavorable wind and humidity conditions for fire propagation (U = 1.67 m/s and RH = 82%), this experiment confirms that such fire can exhibit a dangerous behavior due to the steep slope of the terrain.
Jacky Fayad, Lucile Rossi, Nicolas Frangieh, Carmen Awad, Gilbert Accary, et al.. Numerical study of an experimental high-intensity prescribed fire across Corsican Genista salzmannii vegetation. Fire Safety Journal, 2022, 131, pp.103600. ⟨10.1016/j.firesaf.2022.103600⟩. ⟨hal-04063905⟩
Thierry Marcelli, Lucile Rossi, Gilbert Accary, Carmen Awad, Antoine Burglin, et al.. GOLIAT, a project to develop tools for firefighting and land use planning. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.234-239, 2022, ⟨10.14195/978-989-26-2298-9_38⟩. ⟨hal-03875377⟩ Plus de détails...
The GOLIAT project is a consortium of academics and firefighting operators and land-use planning professionals of Corsica. One goal of GOLIAT project is to provide four operational decision support tools. To reach this goal, a survey of past fires occurred in Corsica since the twentieth century beginning is made. This inventory contributes to build up a database with a web display interface easy to use as fire patterns history. A fire behavior and impact simulator prototype for vegetation fires, a geolocation tool for hot spots using UAV images, and a guide of good practices of prescribed fires in the undergrowth are building. At the same time, experimental fires are carried out to improve knowledge about high intensity fire and the experimental results were compared to the predictions provided by a complete physical 3D model, namely FireStar3D.
Thierry Marcelli, Lucile Rossi, Gilbert Accary, Carmen Awad, Antoine Burglin, et al.. GOLIAT, a project to develop tools for firefighting and land use planning. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.234-239, 2022, ⟨10.14195/978-989-26-2298-9_38⟩. ⟨hal-03875377⟩
François Joseph Chatelon, Miguel Cruz, Jacques-Henri Balbi, Jean-Louis Rossi, Jacky Fayad, et al.. A simplified physical propagation model for surface fires designed for an implementation into fire decision making tools. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.67-73, 2022, ⟨10.14195/978-989-26-2298-9_9⟩. ⟨hal-03875331⟩ Plus de détails...
Nowadays, the needs for decision making tools useful for people involved in firefighting and/or in landscape management becomes more and more crucial, especially with the dramatic increase of the fire dangerousness and fire severity. These tools have to be accurate enough and faster than real time. Up to now, simulators and other tools are mainly based on empirical or semi-empirical models but the lack of physics in their formulation is a major flaw. The Balbi model is a simplified physical propagation model for surface fires which explicitly depends on the topography, the wind velocity and several fuel characteristics. It is a set of algebraic equations built from usual physical conservation laws (mass, momentum etc.) with some strong assumptions. This work aims at providing a new version of the Balbi model in which the resolution of the rate of spread (ROS) does not need any iterative method any more. This simplification is helpful in implementing the equations set into a fire propagation simulator or a coupled fire-atmosphere simulator. It needs a complete change in the structure of the model and the predicted ROS was tested at the field scale against 179 shrubland fires (burnt in Australia, South Africa, Turkey, Portugal, Spain, New Zealand) and 178 Australian grassland fires with a very good agreement with the observed ROS. Two statistical tools are used to check this agreement (Normalized Mean Square Error, NMSE and Mean Absolute Percentage Error, MAPE) and the Fractional Bias (FB) aims at understanding when the model over-predicts or under-predicts the ROS. The proposed model is accurate and its model parameters are calibrated against a small training dataset which makes it fully predictive whatever the environmental and topographic conditions and the fuel bed characteristics. Its more simple structure allows it to be a good candidate for the heart of a simulation or land management decision making tool.
François Joseph Chatelon, Miguel Cruz, Jacques-Henri Balbi, Jean-Louis Rossi, Jacky Fayad, et al.. A simplified physical propagation model for surface fires designed for an implementation into fire decision making tools. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.67-73, 2022, ⟨10.14195/978-989-26-2298-9_9⟩. ⟨hal-03875331⟩
Gauthier Wissocq, Thomas Coratger, Gabriel Farag, Song Zhao, Pierre Boivin, et al.. Restoring the conservativity of characteristic-based segregated models: application to the hybrid lattice Boltzmann method. Physics of Fluids, 2022, 34 (4), pp.046102. ⟨10.1063/5.0083377⟩. ⟨hal-03627520⟩ Plus de détails...
A general methodology is introduced to build conservative numerical models for fluid simulations based on segregated schemes, where mass, momentum and energy equations are solved by different methods. It is here especially designed for developing new numerical discretizations of the total energy equation, adapted to a thermal coupling with the lattice Boltzmann method (LBM). The proposed methodology is based on a linear equivalence with standard discretizations of the entropy equation, which, as a characteristic variable of the Euler system, allows efficiently decoupling the energy equation with the LBM. To this extent, any LBM scheme is equivalently written under a finite-volume formulation involving fluxes, which are further included in the total energy equation as numerical corrections. The viscous heat production is implicitly considered thanks to the knowledge of the LBM momentum flux. Three models are subsequently derived: a first-order upwind, a Lax-Wendroff and a third-order Godunov-type schemes. They are assessed on standard academic test cases: a Couette flow, entropy spot and vortex convections, a Sod shock tube, several two-dimensional Riemann problems and a shock-vortex interaction. Three key features are then exhibited: 1) the models are conservative by construction, recovering correct jump relations across shock waves, 2) the stability and accuracy of entropy modes can be explicitly controlled, 3) the low dissipation of the LBM for isentropic phenomena is preserved.
Gauthier Wissocq, Thomas Coratger, Gabriel Farag, Song Zhao, Pierre Boivin, et al.. Restoring the conservativity of characteristic-based segregated models: application to the hybrid lattice Boltzmann method. Physics of Fluids, 2022, 34 (4), pp.046102. ⟨10.1063/5.0083377⟩. ⟨hal-03627520⟩
François Joseph Chatelon, Jacques-Henri Balbi, Jacky Fayad, Jean-Louis Rossi, Dominique Morvan, et al.. Physical modelling of fires spreading upslope, involved in fire eruption triggering. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.1740-1746, 2022, ⟨10.14195/978-989-26-2298-9_268⟩. ⟨hal-03875354⟩ Plus de détails...
Eruptive fires are one category of extreme fire behaviour. They are characterized by a sudden and unpredictable change in the fire behaviour which represents an extreme danger for people involved in firefighting. The major point is about the mechanism that turns a usual fire behaviour into an eruptive fire behaviour. Among the different explanations found in the literature, the pioneering interpretation consisting in a feedback effect caused by the convective flow induced by the fire under wind and/or slope conditions, has never been disproved with an example of fire accident. The main goal of this work lies in proposing a physical modelling of this fire induced wind. This modelling attempt is derived from the brand-new version of the Balbi model, which is a simplified physical model for surface fires at the field scale that explicitly depends on the triangle of fire (fuel bed, wind and slope). This work is a first step to the modelling of fire eruption. The model tries to represent accurately the acceleration of the fire rate of spread propagating on different sloped terrain under no-wind or weak wind conditions. It is tested against three sets of experiments carried out at the laboratory scale without external wind and against a high intensity experimental fire spreading on a steep sloped terrain and conducted under weak wind conditions in the north-western of Corsica. Some statistical tools are used to compare predicted and observed rate of spread (NMSE, Normalized Mean Square Error and MAPE, Mean Absolute Percentage Error) and to understand the model’s under-predictions or over-predictions trends (FB, Fractional Bias).
François Joseph Chatelon, Jacques-Henri Balbi, Jacky Fayad, Jean-Louis Rossi, Dominique Morvan, et al.. Physical modelling of fires spreading upslope, involved in fire eruption triggering. Advances in Forest Fire Research 2022, 1.ª Edição, Imprensa da Universidade de Coimbra, pp.1740-1746, 2022, ⟨10.14195/978-989-26-2298-9_268⟩. ⟨hal-03875354⟩
T. Coratger, G. Farag, S. Zhao, Pierre Boivin, P. Sagaut. Large-eddy lattice-Boltzmann modeling of transonic flows. Physics of Fluids, 2021, 33 (11), pp.115112. ⟨10.1063/5.0064944⟩. ⟨hal-03424286⟩ Plus de détails...
T. Coratger, G. Farag, S. Zhao, Pierre Boivin, P. Sagaut. Large-eddy lattice-Boltzmann modeling of transonic flows. Physics of Fluids, 2021, 33 (11), pp.115112. ⟨10.1063/5.0064944⟩. ⟨hal-03424286⟩
Oleksandr Dimitrov, Pierrette Guichardon, Isabelle Raspo, Evelyne Neau. Vapor–Liquid Equilibria of the Aqueous and Organic Mixtures Composed of Dipropylene Glycol Methyl Ether, Dipropylene Glycol n -Butyl Ether, and Propylene Glycol n -Butyl Ether. Part II: Modeling Based on the NRTL-PR Model. Industrial and engineering chemistry research, 2021, 60 (30), pp.11513-11524. ⟨10.1021/acs.iecr.1c01545⟩. ⟨hal-03379757⟩ Plus de détails...
Further to the Part I of the present paper, the second Part is concentrated around the VLE modeling of binary mixtures involving the three glycol ethers previously studied experimentally. The authors propose to use the NRTL-PR model for the representation of these non-ideal mixtures. The main difficulties of modelling related to very low vapor pressures and the way of dealing with them are highlighted. The unknown critical parameters for DPM, DPnB and PnB were determined using robust group contribution methods. However, the experimental values of these parameters have never been published before. The main goal of the authors was to obtain the most satisfactory representation of the experimental data provided in the Part I. Some issues that mostly occurred in mixtures involving the PnB as well as in mixtures having very low vapor pressures, were encountered. Nevertheless, we have obtained in general a satisfactory representation of measured points regardless of those issues.
Oleksandr Dimitrov, Pierrette Guichardon, Isabelle Raspo, Evelyne Neau. Vapor–Liquid Equilibria of the Aqueous and Organic Mixtures Composed of Dipropylene Glycol Methyl Ether, Dipropylene Glycol n -Butyl Ether, and Propylene Glycol n -Butyl Ether. Part II: Modeling Based on the NRTL-PR Model. Industrial and engineering chemistry research, 2021, 60 (30), pp.11513-11524. ⟨10.1021/acs.iecr.1c01545⟩. ⟨hal-03379757⟩
Journal: Industrial and engineering chemistry research
Pierre Boivin, M. Tayyab, S. Zhao. Benchmarking a lattice-Boltzmann solver for reactive flows: Is the method worth the effort for combustion?. Physics of Fluids, 2021, 33 (7), pp.071703. ⟨10.1063/5.0057352⟩. ⟨hal-03276189⟩ Plus de détails...
Pierre Boivin, M. Tayyab, S. Zhao. Benchmarking a lattice-Boltzmann solver for reactive flows: Is the method worth the effort for combustion?. Physics of Fluids, 2021, 33 (7), pp.071703. ⟨10.1063/5.0057352⟩. ⟨hal-03276189⟩
Nicolas Frangieh, Gilbert Accary, Jean-Louis Rossi, Dominique Morvan, Sofiane Meradji, et al.. Fuelbreak effectiveness against wind-driven and plume-dominated fires: a 3D numerical study. Fire Safety Journal, 2021, pp.103383. ⟨10.1016/j.firesaf.2021.103383⟩. ⟨hal-03597349⟩ Plus de détails...
The effectiveness of a fuelbreak, created in a homogeneous grassland on a flat terrain, was studied numerically. The analysis relies on 3D numerical simulations that were performed using a detailed physical-fire-model (FIRESTAR3D) based on a multiphase formulation. To avoid border effects, calculations were carried out by imposing periodic boundary conditions along the two lateral sides of the computational domain, reproducing that way a quasi-infinitely long fire front. A total of 72 simulations were carried out for various wind speeds, fuel heights, and fuelbreak widths, which allowed to cover a large spectrum of fire behaviour, ranging from plume-dominated fires to wind-driven fires. The results were classified in three main categories: 1- “Propagation” if fire crossed the fuelbreak with a continuous fire front, 2- “Overshooting” and “Marginal” if fire marginally crosses the fuelbreak with the formation of burning pockets, and 3- “No propagation” if fire does not cross at all the fuelbreak. The ratio of fuelbreak width to fuel height, marking the “Propagation”/“No propagation” transition, was found to be scaled with Byram's convection number Nc as 75.07 × Nc−0.46. The numerical results were also compared to an operational wildfire engineering tool (DIMZAL) dedicated to fuelbreaks dimensioning.
Nicolas Frangieh, Gilbert Accary, Jean-Louis Rossi, Dominique Morvan, Sofiane Meradji, et al.. Fuelbreak effectiveness against wind-driven and plume-dominated fires: a 3D numerical study. Fire Safety Journal, 2021, pp.103383. ⟨10.1016/j.firesaf.2021.103383⟩. ⟨hal-03597349⟩
Arnaud Mura, Song Zhao. Turbulence topology evolution in weakly turbulent premixed flames. Physics of Fluids, 2021, 33 (3), pp.035110. ⟨10.1063/5.0039330⟩. ⟨hal-03442314v2⟩ Plus de détails...
In turbulent premixed flames, not only the isotropy of velocity fluctuations is altered by the thermal expansion effect, the dissipative structure of the turbulent flowfield and the flow topology are also deeply influenced by the flame. Considering the joint probability density function (JPDF) of the second and third invariants of the velocity gradient tensor (VGT)-or its traceless counterpart-is a classical way to educe the topology of turbulent flows at these smallest scales. These quantities are analyzed by considering direct numerical simulation databases of premixed flame kernel growth in homogeneous isotropic turbulence (HIT). Two conditions of turbulence-combustion interaction (TCI) are considered, which correspond to two distinct values of the Bray number. The analysis of the VGT shows that the propagating premixed flame and its associated density variations significantly modify the turbulence structure and flow topology. To understand this behavior as the flow interacts with the flame front, Lagrangian dynamics of the VGT and its invariants are studied by considering the conditional mean rate of change vectors. Special emphasis is thus placed on the Lagrangian evolution equations (LEE) of these invariants. To the best of the authors' knowledge, this is first time that such budgets are scrutinized in premixed combustion conditions. The pressure Hessian contribution to the VGT invariants transport equations is shown to be one of the leading-order terms in this evolution, making it critically important to the flow dynamics and turbulence structure.
Arnaud Mura, Song Zhao. Turbulence topology evolution in weakly turbulent premixed flames. Physics of Fluids, 2021, 33 (3), pp.035110. ⟨10.1063/5.0039330⟩. ⟨hal-03442314v2⟩
Carmen Awad, Nicolas Frangieh, Thierry Marcelli, Gilbert Accary, Dominique Morvan, et al.. Numerical study of the moisture content threshold under prescribed burning conditions. Fire Safety Journal, 2021, pp.103324. ⟨10.1016/j.firesaf.2021.103324⟩. ⟨hal-03595964⟩ Plus de détails...
The safety during prescribed burnings could be achieved by conducting these operations under marginal conditions of fire propagation. This type of fire can or cannot propagate on account of small deviations of the burning conditions, mainly the wind speed, the fuel load, and the fuel moisture-content. In this context, numerical simulations of grassland fires were conducted under marginal conditions in order to relate the moisturecontent threshold of propagation success to the wind speed and the fuel load. The simulations were conducted using FireStar2D, a complete physical 2D fire simulator based on a multiphase modelling approach. The 10 mopen wind speed ranged from 0 to 10 m/s and the fuel load varied from 0.1 kg/m 2 to 0.7 kg/m 2. The effects of wind speed and fuel moisture-content on the fire behaviour and on the flame parameters are discussed. The results show that the moisture threshold increases with the fuel load until it reaches a value beyond which there is no dependence. A similar dependence of the moisture threshold on the wind speed is also observed. Finally, empirical formulae were constructed to relate the fuel moisture content threshold to the wind speed and the fuel loading implicitly through Byram's convective number.
Carmen Awad, Nicolas Frangieh, Thierry Marcelli, Gilbert Accary, Dominique Morvan, et al.. Numerical study of the moisture content threshold under prescribed burning conditions. Fire Safety Journal, 2021, pp.103324. ⟨10.1016/j.firesaf.2021.103324⟩. ⟨hal-03595964⟩
M. Tayyab, S. Zhao, Pierre Boivin. Lattice-Boltzmann modeling of a turbulent bluff-body stabilized flame. Physics of Fluids, 2021, 33 (3), pp.031701. ⟨10.1063/5.0038089⟩. ⟨hal-03160901⟩ Plus de détails...
This letter reports the first large eddy simulation of a turbulent flame using a Lattice-Boltzmann model. To that end, simulation of a bluff-body stabilized propane-air flame is carried out, showing an agreement similar to those available in the literature. Computational costs are also reported, indicating that Lattice-Boltzmann modelling of reactive flows is competitive, with around 1000cpuh required to simulate one residence time in the 1,5m burner.
M. Tayyab, S. Zhao, Pierre Boivin. Lattice-Boltzmann modeling of a turbulent bluff-body stabilized flame. Physics of Fluids, 2021, 33 (3), pp.031701. ⟨10.1063/5.0038089⟩. ⟨hal-03160901⟩
Isabelle Cheylan, Song Zhao, Pierre Boivin, Pierre Sagaut. Compressible pressure-based Lattice-Boltzmann applied to humid air with phase change. Applied Thermal Engineering, 2021, pp.116868. ⟨10.1016/j.applthermaleng.2021.116868⟩. ⟨hal-03180596⟩ Plus de détails...
A new compressible pressure-based Lattice Boltzmann Method is proposed to simulate humid air flows with phase change. The variable density and compressible effects are fully resolved, effectively lifting the Boussinesq approximation commonly used, e.g. for meteorological flows. Previous studies indicate that the Boussinesq assumption can lead to errors up to 25%, but the model remains common, for compressible models often suffer from a lack of stability. In order to overcome this issue, a new pressure-based solver is proposed, exhibiting excellent stability properties. Mass and momentum conservation equations are solved by a hybrid recursive regularized Lattice-Boltzmann approach, whereas the enthalpy and species conservation equations are solved using a finite volume method. The solver is based on a pressure-based method coupled with a predictor-corrector algorithm, and incorporates a humid equation of state, as well as a specific boundary condition treatment for phase change. In particular, boundary conditions that handle mass leakage are also proposed and validated. Three test cases are investigated in order to validate this new approach: the Rayleigh-Bénard instability applied to humid air, the atmospheric rising of a condensing moist bubble, and finally the evaporation of a thin liquid film in a vertical channel. Results indicate that the proposed pressure-based Lattice-Boltzmann model is stable and accurate on all cases.
Isabelle Cheylan, Song Zhao, Pierre Boivin, Pierre Sagaut. Compressible pressure-based Lattice-Boltzmann applied to humid air with phase change. Applied Thermal Engineering, 2021, pp.116868. ⟨10.1016/j.applthermaleng.2021.116868⟩. ⟨hal-03180596⟩
G. Farag, S. Zhao, G. Chiavassa, Pierre Boivin. Consistency study of Lattice-Boltzmann schemes macroscopic limit. Physics of Fluids, 2021, 33 (3), pp.037101. ⟨10.1063/5.0039490⟩. ⟨hal-03160898⟩ Plus de détails...
Owing to the lack of consensus about the way Chapman-Enskog should be performed, a new Taylor-Expansion of Lattice-Boltzmann models is proposed. Contrarily to the Chapman-Enskog expansion, recalled in this manuscript, the method only assumes an su ciently small time step. Based on the Taylor expansion, the collision kernel is reinterpreted as a closure for the stress-tensor equation. Numerical coupling of Lattice-Boltzmann models with other numerical schemes, also encompassed by the method, are shown to create error terms whose scalings are more complex than those obtained via Chapman-Enskog. An athermal model and two compressible models are carefully analyzed through this new scope, casting a new light on each model's consistency with the Navier-Stokes equations.
G. Farag, S. Zhao, G. Chiavassa, Pierre Boivin. Consistency study of Lattice-Boltzmann schemes macroscopic limit. Physics of Fluids, 2021, 33 (3), pp.037101. ⟨10.1063/5.0039490⟩. ⟨hal-03160898⟩
G. Farag, T. Coratger, G. Wissocq, S. Zhao, Pierre Boivin, et al.. A unified hybrid lattice-Boltzmann method for compressible flows: Bridging between pressure-based and density-based methods. Physics of Fluids, 2021, 33 (8), pp.086101. ⟨10.1063/5.0057407⟩. ⟨hal-03324229⟩ Plus de détails...
A unified expression for high-speed compressible segregated consistent lattice Boltzmann methods, namely, pressure-based and improved density-based methods, is given. It is theoretically proved that in the absence of forcing terms, these approaches are strictly identical and can be recast in a unique form. An important result is that the difference with classical density-based methods lies in the addition of fourth-order term in the equilibrium function. It is also shown that forcing terms used to balance numerical errors in both original pressure-based and improved density-based methods can be written in a generalized way. A hybrid segregated efficient lattice-Boltzmann for compressible flow based on this unified model, equipped with a recursive regularization kernel, is proposed and successfully assessed on a wide set of test cases with and without shock waves.
G. Farag, T. Coratger, G. Wissocq, S. Zhao, Pierre Boivin, et al.. A unified hybrid lattice-Boltzmann method for compressible flows: Bridging between pressure-based and density-based methods. Physics of Fluids, 2021, 33 (8), pp.086101. ⟨10.1063/5.0057407⟩. ⟨hal-03324229⟩
T. Lafarge, Pierre Boivin, N. Odier, B. Cuenot. Improved color-gradient method for lattice Boltzmann modeling of two-phase flows. Physics of Fluids, 2021, 33 (8), pp.082110. ⟨10.1063/5.0061638⟩. ⟨hal-03324224⟩ Plus de détails...
This article presents a revised formulation of the color gradient method to model immiscible two-phase flows in the lattice Boltzmann framework. Thanks to this formulation, the color-gradient method is generalized to an arbitrary Equation of State under the form p=f(ρ,ϕ), relieving the nonphysical limitation between density and sound speed ratios present in the original formulation. A fourth-order operator for the equilibrium function is introduced, and its formulation is justified through the calculation of the 3rd order equivalent equation of this numerical scheme. A mathematical development demonstrating how the recoloration phase allows us to solve a conservative Allen–Cahn equation is also proposed. Finally, a novel temporal correction is proposed, improving the numerical stability of the method at high density ratio. Validation tests up to density ratios of 1000 are presented.
T. Lafarge, Pierre Boivin, N. Odier, B. Cuenot. Improved color-gradient method for lattice Boltzmann modeling of two-phase flows. Physics of Fluids, 2021, 33 (8), pp.082110. ⟨10.1063/5.0061638⟩. ⟨hal-03324224⟩
S. Zhao, G. Farag, Pierre Boivin, P. Sagaut. Toward fully conservative hybrid lattice Boltzmann methods for compressible flows. Physics of Fluids, 2020, 32 (12), pp.126118. ⟨10.1063/5.0033245⟩. ⟨hal-03087980⟩ Plus de détails...
S. Zhao, G. Farag, Pierre Boivin, P. Sagaut. Toward fully conservative hybrid lattice Boltzmann methods for compressible flows. Physics of Fluids, 2020, 32 (12), pp.126118. ⟨10.1063/5.0033245⟩. ⟨hal-03087980⟩
Kai Zhang, Aymeric Lamorlette. An extensive numerical study of the burning dynamics of wildland fuel using proposed configuration space. International Journal of Heat and Mass Transfer, 2020, 160, pp.120174. ⟨10.1016/j.ijheatmasstransfer.2020.120174⟩. ⟨hal-02960139⟩ Plus de détails...
Physics-based flame models capable of predicting small-scale fire behaviors reduce computational power needed for predicting fires of large- and giga-scale. However, classical model correlations are often developed for 'free fires' without considering vegetation around. These models may result in inaccurate fire modeling due to wrong 'prior' flame shape estimated from theta similar to wind speed. To overcome this defect, three-dimensional small-scale fires with fireline intensity of 100 KW/m are numerically simulated using large eddy simulation. Fire behaviors such as flame tilt angle and heat transfer mechanisms are extensively studied using a newly proposed configuration space {N-C, CdLAI}. The former one represents the ratio between fire to wind power, and the latter one considering the vegetation effect is for the first time introduced in flame models. Using the configuration space, two model correlations for flame tilt angle and radiative heat power reaching the unburnt fuels are proposed. The flame tilt angle theta is directly related to CdLAI (C-d alpha(s)sigma H-s(F)/2), while inversely related to N-C (2gI/ rho 0C(p,0)T(0)U(0)(3)), in contrast to the model proposed for radiative heat power. Comparisons with several classical models evidenced the capability of new flame models in predicting both free and non-free fires. The limits of the validity of the newly proposed models are also discussed.
Kai Zhang, Aymeric Lamorlette. An extensive numerical study of the burning dynamics of wildland fuel using proposed configuration space. International Journal of Heat and Mass Transfer, 2020, 160, pp.120174. ⟨10.1016/j.ijheatmasstransfer.2020.120174⟩. ⟨hal-02960139⟩
Journal: International Journal of Heat and Mass Transfer
Zhen-Hua Jiang, Xi Deng, Feng Xiao, Chao Yan, Jian Yu. A Higher Order Interpolation Scheme of Finite Volume Method for Compressible Flow on Curvilinear Grids. Communications in Computational Physics, 2020, 28 (4), pp.1609-1638. ⟨10.4208/cicp.OA-2019-0091⟩. ⟨hal-02960145⟩ Plus de détails...
A higher order interpolation scheme based on a multi-stage BVD (Boundary Variation Diminishing) algorithm is developed for the FV (Finite Volume) method on non-uniform, curvilinear structured grids to simulate the compressible turbulent flows. The designed scheme utilizes two types of candidate interpolants including a higher order linear-weight polynomial as high as eleven and a THING (Tangent of Hyperbola for INterface Capturing) function with the adaptive steepness. We investigate not only the accuracy but also the efficiency of the methodology through the cost efficiency analysis in comparison with well-designed mapped WENO (Weighted Essentially Non-Oscillatory) scheme. Numerical experimentation including benchmark broadband turbulence problem as well as real-life wall-bounded turbulent flows has been carried out to demonstrate the potential implementation of the present higher order interpolation scheme especially in the ILES (Implicit Large Eddy Simulation) of compressible turbulence.
Zhen-Hua Jiang, Xi Deng, Feng Xiao, Chao Yan, Jian Yu. A Higher Order Interpolation Scheme of Finite Volume Method for Compressible Flow on Curvilinear Grids. Communications in Computational Physics, 2020, 28 (4), pp.1609-1638. ⟨10.4208/cicp.OA-2019-0091⟩. ⟨hal-02960145⟩
G. Farag, S. Zhao, T. Coratger, Pierre Boivin, G. Chiavassa, et al.. A pressure-based regularized lattice-Boltzmann method for the simulation of compressible flows. Physics of Fluids, 2020, 32 (6), pp.066106. ⟨10.1063/5.0011839⟩. ⟨hal-02885427⟩ Plus de détails...
A new pressure-based Lattice-Boltzmann method (HRR-p) is proposed for the simulation of flows for Mach numbers ranging from 0 to 1.5. Compatible with nearest neighbor lattices (e.g. D3Q19), the model consists of a predictor step comparable to classical athermal Lattice-Boltzmann methods, appended with a fully local and explicit correction step for the pressure. Energy conservation-for which the Hermi-tian quadrature is not accurate enough on such lattice-is solved via a classical finite volume MUSCL-Hancock scheme based on the entropy equation. The Euler part of the model is then validated for the transport of three canonical modes (vortex, en-tropy, and acoustic propagation), while its diffusive/viscous properties are assessed via thermal Couette flow simulations. All results match the analytical solutions, with very limited dissipation. Lastly, the robustness of the method is tested in a one dimensional shock tube and a two-dimensional shock-vortex interaction.
G. Farag, S. Zhao, T. Coratger, Pierre Boivin, G. Chiavassa, et al.. A pressure-based regularized lattice-Boltzmann method for the simulation of compressible flows. Physics of Fluids, 2020, 32 (6), pp.066106. ⟨10.1063/5.0011839⟩. ⟨hal-02885427⟩
Siengdy Tann, Xi Deng, Yuya Shimizu, Raphaël Loubère, Feng Xiao. Solution property preserving reconstruction for finite volume scheme: a boundary variation diminishing+multidimensional optimal order detection framework. International Journal for Numerical Methods in Fluids, 2020, 92 (6), pp.603-634. ⟨10.1002/fld.4798⟩. ⟨hal-02618891⟩ Plus de détails...
Xi Deng, Pierre Boivin. Diffuse interface modelling of reactive multi-phase flows applied to a sub-critical cryogenic jet. Applied Mathematical Modelling, 2020, ⟨10.1016/j.apm.2020.04.011⟩. ⟨hal-02561937⟩ Plus de détails...
In order to simulate cryogenic H 2 − O 2 jets under subcritical condition, a numerical model is constructed to solve compressible reactive multi-component flows which involve complex multi-physics processes such as moving material interfaces, shock waves, phase transition and combustion. The liquid and reactive gaseous mixture are described by a homogeneous mixture model with diffusion transport for heat, momentum and species. A hybrid thermodynamic closure strategy is proposed to construct an equation of state (EOS) for the mixture. The phase transition process is modeled by a recent fast relaxation method which gradually reaches the thermo-chemical equilibrium without iterative process. A simplified transport model is also implemented to ensure the accurate behavior in the limit of pure fluids and maintain computational efficiency. Last, a 12-step chemistry model is included to account for hydrogen combustion. Then the developed numerical model is solved with the finite volume method where a low dissipation AUSM (advection upstream splitting method) Riemann solver is extended for multi-component flows. A homogeneous reconstruction strategy compatible with the homogeneous mixture model is adopted to prevent numerical oscillations across material interfaces. Having included these elements, the model is validated on a number of canonical configurations, first for multi-phase flows, and second for reactive flows. These tests allow recovery of the expected behavior in both the multiphase and reactive limits, and the model capability is further demonstrated on a 2D burning cryogenic H 2 − O 2 jet, in a configuration reminiscent of rocket engine ignition.
Xi Deng, Pierre Boivin. Diffuse interface modelling of reactive multi-phase flows applied to a sub-critical cryogenic jet. Applied Mathematical Modelling, 2020, ⟨10.1016/j.apm.2020.04.011⟩. ⟨hal-02561937⟩
Kai Zhang, Salman Verma, Arnaud Trouvé, Aymeric Lamorlette. A study of the canopy effect on fire regime transition using an objectively defined Byram convective number. Fire Safety Journal, 2020, 112, pp.102950. ⟨10.1016/j.firesaf.2020.102950⟩. ⟨hal-02469260⟩ Plus de détails...
Kai Zhang, Salman Verma, Arnaud Trouvé, Aymeric Lamorlette. A study of the canopy effect on fire regime transition using an objectively defined Byram convective number. Fire Safety Journal, 2020, 112, pp.102950. ⟨10.1016/j.firesaf.2020.102950⟩. ⟨hal-02469260⟩
Xi Deng, Yuya Shimizu, Bin Xie, Feng Xiao. Constructing higher order discontinuity-capturing schemes with upwind-biased interpolations and boundary variation diminishing algorithm. Computers and Fluids, 2020, 200, pp.104433. ⟨10.1016/j.compfluid.2020.104433⟩. ⟨hal-02892513⟩ Plus de détails...
Based on the fifth-order scheme in our previous work (Deng et. al (2019) [28]), a new framework of constructing very high order discontinuity-capturing schemes is proposed for finite volume method. These schemes, so-called PnTm - BVD (polynomial of n-degree and THINC function of m-level reconstruction based on BVD algorithm), are designed by employing high-order upwind-biased interpolations and THINC (Tangent of Hyperbola for INterface Capturing) functions with adaptive steepness as the reconstruction candidates. The final reconstruction function in each cell is determined with a multi-stage BVD (Boundary Variation Diminishing) algorithm so as to effectively control numerical oscillation and dissipation. We devise the new schemes up to eleventh order in an efficient way by directly increasing the order of the underlying upwind scheme using high order polynomials. The analysis of the spectral property and accuracy tests show that the new reconstruction strategy well preserves the low-dissipation property of the underlying upwind schemes with high-order polynomials for smooth solution over all wave numbers and realizes n + 1 order convergence rate. The performance of new schemes is examined through widely used benchmark tests, which demonstrate that the proposed schemes are capable of simultaneously resolving small-scale flow features with high resolution and capturing discontinuities with low dissipation. With outperforming results and simplicity in algorithm, the new reconstruction strategy shows great potential as an alternative numerical framework for computing nonlinear hyperbolic conservation laws that have discontinuous and smooth solutions of different scales.
Xi Deng, Yuya Shimizu, Bin Xie, Feng Xiao. Constructing higher order discontinuity-capturing schemes with upwind-biased interpolations and boundary variation diminishing algorithm. Computers and Fluids, 2020, 200, pp.104433. ⟨10.1016/j.compfluid.2020.104433⟩. ⟨hal-02892513⟩
Isabelle Raspo, Evelyne Neau. An empirical correlation for the relative permittivity of liquids in a wide temperature range: application to the modeling of electrolyte systems with a GE/EoS approach.. Fluid Phase Equilibria, 2020, 506, pp.112371. ⟨10.1016/j.fluid.2019.112371⟩. ⟨hal-02325903⟩ Plus de détails...
Relative permittivity, also known as static dielectric constant, is a key property of solvents in electrolyte solutions. It strongly influences the solubility of solutes and, therefore, it can be used as a predictive tool in chemical engineering processes. Relative permittivity also plays an essential role in the modeling of phase equilibria of electrolyte systems, since it is involved in the Debye-Hückel model and in the Mean Spherical Approximation, commonly used to represent long-range interactions between ions. In this paper, we propose a new temperature-dependent correlation for the relative permittivity of liquid water, methanol and ethanol, valid in a wide temperature range, including very high temperatures. Comparison with other literature equations evidenced that the main interest of the proposed correlation is to allow satisfactory predictions of the relative permittivity, not only in the range of validity of other literature models, but also in the high temperature domain, including supercritical temperatures for water. The new correlation is then used with the NRTL-PRA EoS to predict vapor pressure of water with several salts, including single electrolytes and two-salts mixtures; it must be noted that the modeling presented in this work is relevant for any GE/EoS model, since in this case (binary interactions between water and ions being equal to zero), the excess Gibbs energy reduces to the Long-Range term derived from the Pitzer-Debye-Hückel model. A temperature-dependent correction of the solvent relative permittivity is proposed to account for its dependence on ion mole fraction in this Long-Range term. Results thus obtained show that this correction leads to an accurate prediction both: for vapor pressures of aqueous electrolyte solutions in a very wide temperature domain and for the modeling of vapor-liquid equilibria of methanol-water and ethanol-water mixtures with several salts.
Isabelle Raspo, Evelyne Neau. An empirical correlation for the relative permittivity of liquids in a wide temperature range: application to the modeling of electrolyte systems with a GE/EoS approach.. Fluid Phase Equilibria, 2020, 506, pp.112371. ⟨10.1016/j.fluid.2019.112371⟩. ⟨hal-02325903⟩
Muhammad Tayyab, Basile Radisson, Christophe Almarcha, B. Denet, Pierre Boivin. Experimental and numerical Lattice-Boltzmann investigation of the Darrieus-Landau instability. Combustion and Flame, 2020, 221, pp.103-109. ⟨10.1016/j.combustflame.2020.07.030⟩. ⟨hal-02921517⟩ Plus de détails...
We present an experimental and numerical investigation of the Darrieus- Landau instability in a quasi two-dimensional Hele-Shaw cell. Experiments and Lattice-Boltzmann numerical simulations are compared with Darrieus- Landau analytical theory, showing an excellent agreement for the exponential growth rate of the instability in the linear regime. The negative growth rate – second solution of the dispersion relation – was also measured numerically for the first time to the authors’ knowledge. Experiments and numerical simulations were then carried out beyond the cutoff wavelength, providing good agreement even in the unexplored regime where Darrieus-Landau is supplanted by diffusive stabilization. Lastly, the non-linear evolution involving the merging of crests on the experimental flame front is also successfully recovered using both the Michelson-Sivashinsky equation integration and the Lattice-Boltzmann simulation.
Muhammad Tayyab, Basile Radisson, Christophe Almarcha, B. Denet, Pierre Boivin. Experimental and numerical Lattice-Boltzmann investigation of the Darrieus-Landau instability. Combustion and Flame, 2020, 221, pp.103-109. ⟨10.1016/j.combustflame.2020.07.030⟩. ⟨hal-02921517⟩
Implicit large eddy simulation (ILES) of compressible turbulence with shock capturing schemes requires wide investigations and numerical experiments. In this study, a newly proposed PnTm - BVD (polynomial of n-degree and THINC function of m-level reconstruction based on BVD algorithm) shock capturing scheme is introduced to simulate compressible turbulence flow with ILES. The new scheme is designed by employing high-order linear-weight polynomials and THINC (Tangent of Hyperbola for INterface Capturing) functions with adaptive steepness as the reconstruction candidates. The final reconstruction function in each cell is determined with a multi-stage BVD (Boundary Variation Diminishing) algorithm so as to effectively control numerical oscillation and dissipation. Numerical tests involving shock waves and broadband turbulence are conducted in comparison with WENO (Weighted Essentially Non-oscillatory) schemes which are widely used in ILES. The results demonstrate performing ILES with PnTm- BVD scheme is able to obtain higher resolution and more faithful results than WENO does. Importantly, the superiority of PnTm-BVD becomes more notable in high wave-number region. Thus this paper provides and verifies a new scheme which is promising in providing high-resolution results for real-case ILES of compressible turbulence flow.
Xi Deng, Zhen-Hua Jiang, Feng Xiao, Chao Yan. Implicit large eddy simulation of compressible turbulence flow with PnTm − BVD scheme. Applied Mathematical Modelling, 2020, 77, pp.17-31. ⟨10.1016/j.apm.2019.07.022⟩. ⟨hal-03235122⟩
Erwan Deriaz, Pierre Haldenwang. Non-linear CFL Conditions Issued from the von Neumann Stability Analysis for the Transport Equation. Journal of Scientific Computing, 2020, 85 (1), pp.5. ⟨10.1007/s10915-020-01302-0⟩. ⟨hal-03231866⟩ Plus de détails...
This paper presents a theory of the possible non-linear stability conditions encountered in the simulation of convection dominated problems. Its main objective is to study and justify original CFL-like stability conditions thanks to the von Neumann stability analysis. In particular, we exhibit a wide variety of stability conditions of the type t ≤ C x α with t the time step, x the space step, and α a rational number within the interval [1, 2]. Numerical experiments corroborate these theoretical results.
Erwan Deriaz, Pierre Haldenwang. Non-linear CFL Conditions Issued from the von Neumann Stability Analysis for the Transport Equation. Journal of Scientific Computing, 2020, 85 (1), pp.5. ⟨10.1007/s10915-020-01302-0⟩. ⟨hal-03231866⟩
Jacques Henri Balbi, François Joseph Chatelon, Dominique Morvan, Jean Louis Rossi, Thierry Marcelli, et al.. A convective–radiative propagation model for wildland fires. International Journal of Wildland Fire, 2020, ⟨10.1071/WF19103⟩. ⟨hal-03251626⟩ Plus de détails...
The 'Balbi model' is a simplified steady-state physical propagation model for surface fires that considers radiative heat transfer from the surface area of burning fuel particles as well as from the flame body. In this work, a completely new version of this propagation model for wildand fires is proposed. Even if, in the present work, this model is confined to laboratory experiments, its purpose is to be used at a larger scale in the field under operational conditions. This model was constructed from a radiative propagation model with the addition of a convective heat transfer term resulting from the impingement of packets of hot reacting gases on unburnt fuel elements located at the base of the flame. The flame inside the fuel bed is seen as the 'fingers of fire' described in the literature. The proposed model is physics-based, faster than real time and fully predictive, which means that model parameters do not change from one experiment to another. The predicted rate of spread is applied to a large set of laboratory experiments (through homogeneous pine needles and excelsior fuel beds) and is compared with the predictions of both a very simple empirical model (Catchpole) and a detailed physical model (FireStar2D).
Jacques Henri Balbi, François Joseph Chatelon, Dominique Morvan, Jean Louis Rossi, Thierry Marcelli, et al.. A convective–radiative propagation model for wildland fires. International Journal of Wildland Fire, 2020, ⟨10.1071/WF19103⟩. ⟨hal-03251626⟩
Jacques Henri Balbi, François Joseph Chatelon, Dominique Morvan, Jean Louis Rossi, Thierry Marcelli, et al.. A convective–radiative propagation model for wildland fires. International Journal of Wildland Fire, 2020, ⟨10.1071/WF19103⟩. ⟨hal-02570863⟩ Plus de détails...
Jacques Henri Balbi, François Joseph Chatelon, Dominique Morvan, Jean Louis Rossi, Thierry Marcelli, et al.. A convective–radiative propagation model for wildland fires. International Journal of Wildland Fire, 2020, ⟨10.1071/WF19103⟩. ⟨hal-02570863⟩
Kai Zhang, Aymeric Lamorlette. An extensive numerical study of the burning dynamics of wildland fuel using proposed configuration space. International Journal of Heat and Mass Transfer, 2020, 160, pp.120174. ⟨10.1016/j.ijheatmasstransfer.2020.120174⟩. ⟨hal-03232086⟩ Plus de détails...
Physics-based flame models capable of predicting small-scale fire behaviors reduce computational power needed for predicting fires of large- and giga-scale. However, classical model correlations are often developed for 'free fires' without considering vegetation around. These models may result in inaccurate fire modeling due to wrong 'prior' flame shape estimated from theta similar to wind speed. To overcome this defect, three-dimensional small-scale fires with fireline intensity of 100 KW/m are numerically simulated using large eddy simulation. Fire behaviors such as flame tilt angle and heat transfer mechanisms are extensively studied using a newly proposed configuration space {N-C, CdLAI}. The former one represents the ratio between fire to wind power, and the latter one considering the vegetation effect is for the first time introduced in flame models. Using the configuration space, two model correlations for flame tilt angle and radiative heat power reaching the unburnt fuels are proposed. The flame tilt angle theta is directly related to CdLAI (C-d alpha(s)sigma H-s(F)/2), while inversely related to N-C (2gI/ rho 0C(p,0)T(0)U(0)(3)), in contrast to the model proposed for radiative heat power. Comparisons with several classical models evidenced the capability of new flame models in predicting both free and non-free fires. The limits of the validity of the newly proposed models are also discussed.
Kai Zhang, Aymeric Lamorlette. An extensive numerical study of the burning dynamics of wildland fuel using proposed configuration space. International Journal of Heat and Mass Transfer, 2020, 160, pp.120174. ⟨10.1016/j.ijheatmasstransfer.2020.120174⟩. ⟨hal-03232086⟩
Journal: International Journal of Heat and Mass Transfer
Dan Feng, Laure Malleret, Guillaume Chiavassa, Olivier Boutin, Audrey Soric. Biodegradation capabilities of acclimated activated sludge towards glyphosate: Experimental study and kinetic modeling. Biochemical Engineering Journal, 2020, 161, pp.107643. ⟨10.1016/j.bej.2020.107643⟩. ⟨hal-02960167⟩ Plus de détails...
The acclimation process of activated sludge from a wastewater treatment plant for degradation of glyphosate and its biodegradation kinetics were studied in a batch reactor. The parameters monitored included the concentrations of glyphosate, as well as aminomethylphosphonic acid (AMPA), its main metabolite, total organic carbon (TOC), pH, dissolved oxygen (DO) and biomass concentration. M the end of the acclimation process, glyphosate removal efficiency of the acclimated sludge was compared to the fresh sludge one. The results showed that the acclimation process highly increased degradation efficiency. Complete glyphosate removal has been achieved during kinetics experiments. Glyphosate removal kinetic of the acclimated sludge was modeled by Monod model that accurately fitted the experimental results with a maximum growth rate (mu(max)) of 0.34 h(-1) and half-saturation constant (K-s) of 1600 mg L-1. Finally, a biodegradation pathway of glyphosate used as carbon source was proposed.
Dan Feng, Laure Malleret, Guillaume Chiavassa, Olivier Boutin, Audrey Soric. Biodegradation capabilities of acclimated activated sludge towards glyphosate: Experimental study and kinetic modeling. Biochemical Engineering Journal, 2020, 161, pp.107643. ⟨10.1016/j.bej.2020.107643⟩. ⟨hal-02960167⟩
M. Tayyab, S. Zhao, Y. Feng, Pierre Boivin. Hybrid regularized Lattice-Boltzmann modelling of premixed and non-premixed combustion processes. Combustion and Flame, 2020, 211, pp.173-184. ⟨10.1016/j.combustflame.2019.09.029⟩. ⟨hal-02346556⟩ Plus de détails...
A Lattice-Boltzmann model for low-Mach reactive flows is presented, built upon our recently published model (Comb & Flame, 196, 2018). The approach is hybrid and couples a Lattice-Boltzmann solver for the resolution of mass and momentum conservation and a finite difference solver for the energy and species conservation. Having lifted the constant thermodynamic and transport properties assumptions, the model presented now fully accounts for the classical reactive flow thermodynamic closure: each component is assigned NASA coefficients for calculating its thermodynamic properties. A temperature-dependent viscosity is considered, from which are deduced thermo-diffusive properties via specification of Prandtl and component-specific Schmidt numbers. Another major improvement from our previous contribution is the derivation of an advanced collision kernel compatible of multi-component reactive flows stable in high shear flows. Validation is carried out first on premixed configurations, through simulation of the planar freely propagating flame, the growth of the associated Darrieus-Landau instability and three regimes of flame-vortex interaction. A double shear layer test case including a flow-stabilized diffusion flame is then presented and results are compared with DNS simulations, showing excellent agreement.
M. Tayyab, S. Zhao, Y. Feng, Pierre Boivin. Hybrid regularized Lattice-Boltzmann modelling of premixed and non-premixed combustion processes. Combustion and Flame, 2020, 211, pp.173-184. ⟨10.1016/j.combustflame.2019.09.029⟩. ⟨hal-02346556⟩
Implicit large eddy simulation (ILES) of compressible turbulence with shock capturing schemes requires wide investigations and numerical experiments. In this study, a newly proposed PnTm - BVD (polynomial of n-degree and THINC function of m-level reconstruction based on BVD algorithm) shock capturing scheme is introduced to simulate compressible turbulence flow with ILES. The new scheme is designed by employing high-order linear-weight polynomials and THINC (Tangent of Hyperbola for INterface Capturing) functions with adaptive steepness as the reconstruction candidates. The final reconstruction function in each cell is determined with a multi-stage BVD (Boundary Variation Diminishing) algorithm so as to effectively control numerical oscillation and dissipation. Numerical tests involving shock waves and broadband turbulence are conducted in comparison with WENO (Weighted Essentially Non-oscillatory) schemes which are widely used in ILES. The results demonstrate performing ILES with PnTm- BVD scheme is able to obtain higher resolution and more faithful results than WENO does. Importantly, the superiority of PnTm-BVD becomes more notable in high wave-number region. Thus this paper provides and verifies a new scheme which is promising in providing high-resolution results for real-case ILES of compressible turbulence flow.
Xi Deng, Zhen-Hua Jiang, Feng Xiao, Chao Yan. Implicit large eddy simulation of compressible turbulence flow with PnTm − BVD scheme. Applied Mathematical Modelling, 2020, 77, pp.17-31. ⟨10.1016/j.apm.2019.07.022⟩. ⟨hal-02892550⟩
Nicolas Frangieh, Gilbert Accary, Dominique Morvan, Sofiane Meradji, Oleg Bessonov. Wildfires front dynamics: 3D structures and intensity at small and large scales. Combustion and Flame, 2020, 211, pp.54-67. ⟨10.1016/j.combustflame.2019.09.017⟩. ⟨hal-02892557⟩ Plus de détails...
The 3D structure of a fire front propagating through a homogeneous porous solid-fuel layer was studied numerically at laboratory and field scales. At laboratory scale, wind-tunnel fires propagating through laser-cut cardboard fuel were numerically reproduced, while at field scale, simulations of grassland fires with quasi-infinite fire front were carried out for different wind speeds. These simulations were performed using FIRESTAR3D, based on a multiphase formulation that includes the main physical phenomena governing fire behavior. An unsteady RANS approach and a Large Eddy Simulation (LES) approach were used to simulate the reactive turbulent flow, whereas turbulent combustion was modeled using Eddy Dissipation Concept (EDC). Unlike other 3D wildfire tools available in the community, such as FIRETEC and WFDS, the model is based on an implicit, low-Mach number resolution of the governing equations, and makes no empirical assumptions in the resolution of the radiative transfer equation. The comparison with the experimental data concerned mainly the Rate of Spread (ROS) of fire, the fireline intensity, the flame-zone depth, and the wavelength characterizing the crest-and-trough structure of the fire front along the transverse direction. Particular attention was drawn to the similitude in the fire front dynamics between small and large scales. In order to highlight the physical mechanisms responsible for this dynamics, a dimensional analysis was carried out by introducing Byram's convection number N-C based on the fireline intensity and Froude's numbers Fr based on the characteristic wavelength of the fire-front structure. The analysis shows that all the results (wind-tunnel fires and grassland fires, experimental and numerical) collapsed on a single scaling law in the form Fr = N-C(-)2/3.
Nicolas Frangieh, Gilbert Accary, Dominique Morvan, Sofiane Meradji, Oleg Bessonov. Wildfires front dynamics: 3D structures and intensity at small and large scales. Combustion and Flame, 2020, 211, pp.54-67. ⟨10.1016/j.combustflame.2019.09.017⟩. ⟨hal-02892557⟩
Gilbert Accary, Duncan Sutherland, Nicolas Frangieh, Khalid Moinuddin, Ibrahim Shamseddine, et al.. Physics-Based Simulations of Flow and Fire Development Downstream of a Canopy. Atmosphere, 2020, 11 (7), pp.683. ⟨10.3390/atmos11070683⟩. ⟨hal-02957445⟩ Plus de détails...
The behavior of a grassland fire propagating downstream of a forest canopy has been simulated numerically using the fully physics-based wildfire model FIRESTAR3D. This configuration reproduces quite accurately the situation encountered when a wildfire spreads from a forest to an open grassland, as can be the case in a fuel break or a clearing, or during a prescribed burning operation. One of the objectives of this study was to evaluate the impact of the presence of a canopy upstream of a grassfire, especially the modifications of the local wind conditions before and inside a clearing or a fuel break. The knowledge of this kind of information constitutes a major element in improving the safety conditions of forest managers and firefighters in charge of firefighting or prescribed burning operations in such configurations. Another objective was to study the behavior of the fire under realistic turbulent flow conditions, i.e., flow resulting from the interaction between an atmospheric boundary layer (ABL) with a surrounding canopy. Therefore, the study was divided into two phases. The first phase consisted of generating an ABL/canopy turbulent flow above a pine forest (10 m high, 200 m long) using periodic boundary conditions along the streamwise direction. Large Eddy Simulations (LES) were carried out for a sufficiently long time to achieve a quasi-fully developed turbulence. The second phase consisted of simulating the propagation of a surface fire through a grassland, bordered upstream by a forest section (having the same characteristics used for the first step), while imposing the turbulent flow obtained from the first step as a dynamic inlet condition to the domain. The simulations were carried out for a wind speed that ranged between 1 and 12 m/s; these values have allowed the simulations to cover the two regimes of propagation of surfaces fires, namely plume-dominated and wind-driven fires.
Gilbert Accary, Duncan Sutherland, Nicolas Frangieh, Khalid Moinuddin, Ibrahim Shamseddine, et al.. Physics-Based Simulations of Flow and Fire Development Downstream of a Canopy. Atmosphere, 2020, 11 (7), pp.683. ⟨10.3390/atmos11070683⟩. ⟨hal-02957445⟩
Bin Xie, Xi Deng, Shijun Liao. High-fidelity solver on polyhedral unstructured grids for low-Mach number compressible viscous flow. Computer Methods in Applied Mechanics and Engineering, 2019, 357, pp.112584. ⟨10.1016/j.cma.2019.112584⟩. ⟨hal-02467981⟩ Plus de détails...
In this article, we developed an unstructured fluid solver based on finite volume framework for the low-Mach number compressible flows. The present method, so-called FVMS3 (Finite Volume method based on Merged Stencil with 3rd-order reconstruction) formulates two different numerical procedures for spatial reconstructions based on the quadratic polynomial which is performed by using least-square approximations on a merged stencil. In order to improve the reconstruction for discontinuities, we propose the limiting projection approach and smoothness adaptive fitting (SAF) scheme to suppress the numerical oscillation and limit the numerical dissipation. The resulting discretization algorithm that combines FVMS3 with SAF-based limiting projection scheme has third-order accuracy and resolves both smooth and non-smooth solutions with excellent quality. Additionally, a novel numerical model has been proposed by introducing the advection upstream splitting method (AUSM) flux into the pressure projection formulation which results in a unified scheme that works uniformly up to the incompressible limit. The fluid solver that integrates all above new efforts provides high-fidelity solutions for compressible viscous flows particularly for the low Mach regime. The performance of this new solver is verified by numerous benchmark tests. Our numerical results show that the proposed scheme gives accurate and robust solutions for a wide spectrum of test problems.
Bin Xie, Xi Deng, Shijun Liao. High-fidelity solver on polyhedral unstructured grids for low-Mach number compressible viscous flow. Computer Methods in Applied Mechanics and Engineering, 2019, 357, pp.112584. ⟨10.1016/j.cma.2019.112584⟩. ⟨hal-02467981⟩
Journal: Computer Methods in Applied Mechanics and Engineering
Siengdy Tann, Xi Deng, Yuya Shimizu, Raphaël Loubère, Feng Xiao. Solution Property Preserving Reconstruction for Finite Volume Scheme: a BVD+MOOD framework. International Journal for Numerical Methods in Fluids, In press, ⟨10.1002/fld.4798⟩. ⟨hal-02397156⟩ Plus de détails...
The purpose of this work is to build a general framework to reconstruct the underlying fields within a Finite Volume (FV) scheme solving a hyperbolic system of PDEs (Partial Differential Equations). In an FV context, the data are piece-wise constants per computational cell and the physical fields are reconstructed taking into account neighbor cell values. These reconstructions are further used to evaluate the physical states usually used to feed a Riemann solver which computes the associated numerical fluxes. The physical field reconstructions must obey some properties linked to the system of PDEs such as the positivity, but also some numerically based ones, like an essentially non-oscillatory behaviour. Moreover, the reconstructions should be high accurate for smooth flows and robust/stable for discontinuous solutions. To ensure a Solution Property Preserving Reconstruction, we introduce a methodology to blend high/low order polynomials and hyperbolic tangent reconstructions. A Boundary Variation Diminishing (BVD) algorithm is employed to select the best reconstruction in each cell. An a posteriori MOOD detection procedure is employed to ensure the positivity by re-computing the rare problematic cells using a robust first-order FV scheme. We illustrate the performance of the proposed scheme via the numerical simulations for some benchmark tests which involve vacuum or near vacuum states, strong discontinuities and also smooth flows. The proposed scheme maintains high accuracy on smooth profile, preserves the positivity and can eliminate the oscillations in the vicinity of discontinuities while maintaining sharper discontinuity with superior solution quality compared to classical high accurate FV schemes.
Siengdy Tann, Xi Deng, Yuya Shimizu, Raphaël Loubère, Feng Xiao. Solution Property Preserving Reconstruction for Finite Volume Scheme: a BVD+MOOD framework. International Journal for Numerical Methods in Fluids, In press, ⟨10.1002/fld.4798⟩. ⟨hal-02397156⟩
Journal: International Journal for Numerical Methods in Fluids
Yongliang Feng, Pierre Boivin, Jérome Jacob, Pierre Sagaut. Hybrid recursive regularized lattice Boltzmann simulation of humid air with application to meteorological flows. Physical Review E , 2019. ⟨hal-02265484⟩ Plus de détails...
An extended version of the hybrid recursive regularized Lattice-Boltzmann model which incorporates external force is developed to simulate humid air flows with phase change mechanisms under the Boussinesq approximation. Mass and momentum conservation equations are solved by a regu-larized lattice Boltzmann approach well suited for high Reynolds number flows, whereas the energy and humidity related equations are solved by a finite volume approach. Two options are investigated to account for cloud formation in atmospheric flow simulations. The first option considers a single conservation equation for total water and an appropriate invariant variable of temperature. In the other approach, liquid and vapor are considered via two separated equations, and phase transition is accounted for via a relaxation procedure. The obtained models are then systematically validated on four well-established benchmark problems including a double diffusive Rayleigh Bénard convection of humid air, 2D and 3D thermal moist rising bubble under convective atmospheric environment as well as a shallow cumulus convection in framework of large-eddy simulation.
Yongliang Feng, Pierre Boivin, Jérome Jacob, Pierre Sagaut. Hybrid recursive regularized lattice Boltzmann simulation of humid air with application to meteorological flows. Physical Review E , 2019. ⟨hal-02265484⟩
G. Farag, Pierre Boivin, P. Sagaut. Interaction of two-dimensional spots with a heat releasing/absorbing shock wave: linear interaction approximation results. Journal of Fluid Mechanics, 2019, 871, pp.865-895. ⟨10.1017/jfm.2019.324⟩. ⟨hal-02142649⟩ Plus de détails...
The canonical interaction between a two-dimensional weak Gaussian disturbance (en-tropy spot, density spot, weak vortex) with an exothermic/endothermic planar shock wave is studied via the Linear Interaction Approximation. To this end, a unified framework based on an extended Kovasznay decomposition that simultaneously accounts for non-acoustic density disturbances along with a poloidal-toroidal splitting of the vorticity mode and for heat-release is proposed. An extended version of Chu's definition for the energy of disturbances in compressible flows encompassing multi-component mixtures of gases is also proposed. This new definition precludes spurious non-normal phenomena when computing the total energy of extended Kovasznay modes. Detailed results are provided for three cases, along with fully general expressions for mixed solutions that combine incoming vortical, entropy and density disturbances.
G. Farag, Pierre Boivin, P. Sagaut. Interaction of two-dimensional spots with a heat releasing/absorbing shock wave: linear interaction approximation results. Journal of Fluid Mechanics, 2019, 871, pp.865-895. ⟨10.1017/jfm.2019.324⟩. ⟨hal-02142649⟩
Pierre Haldenwang, Braulio Bernales, Pierrette Guichardon, Nelson Ibaseta. Simple Theoretical Results on Reversible Fouling in Cross-Flow Membrane Filtration. Membranes, 2019, Application of Membrane Filtration in Industrial Processes, and in the Treatment of Water and Industrial Wastewater), 9 (4), pp.48. ⟨10.3390/membranes9040048⟩. ⟨hal-02109009⟩ Plus de détails...
In cross-flow membrane filtration, fouling results from material deposit which clogs the membrane inner surface. This hinders filtration, which experiences the so-called limiting flux. Among the models proposed by the literature, we retain a simple one: a steady-state reversible fouling is modelled with the use of a single additional parameter, i.e., N d , the ratio of the critical concentration for deposition to the feed concentration at inlet. To focus on fouling, viscous pressure drop and osmotic (counter-)pressure have been chosen low. It results in a minimal model of fouling. Solved thoroughly with the numerical means appropriate to enforce the nonlinear coupling between permeation and concentration polarization, the model delivers novel information. It first shows that permeation is utterly governed by solute transfer, the relevant non-dimensional quantities being hence limited to N d and Pe in , the transverse Péclet number. Furthermore, when the role played by N d and moderate Pe in (say Pe in < 40) is investigated, all results can be interpreted with the use of a single non-dimensional parameter, F l , the so-called fouling number, which simply reads F l ≡ Pe in N −1 d. Now rendered possible, the overall fit of the numerical data allows us to put forward analytical final expressions, which involve all the physical parameters and allow us to retrieve the experimental trends.
Pierre Haldenwang, Braulio Bernales, Pierrette Guichardon, Nelson Ibaseta. Simple Theoretical Results on Reversible Fouling in Cross-Flow Membrane Filtration. Membranes, 2019, Application of Membrane Filtration in Industrial Processes, and in the Treatment of Water and Industrial Wastewater), 9 (4), pp.48. ⟨10.3390/membranes9040048⟩. ⟨hal-02109009⟩
Xi Deng, Pierre Boivin, Feng Xiao. A new formulation for two-wave Riemann solver accurate at contact interfaces. Physics of Fluids, 2019, 31 (4), pp.046102. ⟨10.1063/1.5083888⟩. ⟨hal-02100764⟩ Plus de détails...
This study proposes a new formulation for Harten, Lax and van Leer (HLL) type Riemann solver which is capable of solving contact discontinuities accurately but with robustness for strong shock. It is well known that the original HLL, which has incomplete wave structures, is too dissipative to capture contact disconti-nuities accurately. On the other side, contact-capturing approximate Riemann solvers such as Harten, Lax and van Leer with Contact (HLLC) usually suffer from spurious solutions, also called carbuncle phenomenon, for strong shock. In this work a new accurate and robust HLL-type formulation, so-called HLL-BVD (HLL Riemann solver with BVD) is proposed by modifying the original HLL with BVD (boundary variation dimin-shing) algorithm. Instead of explicitly recovering the complete wave structures like the way of HLLC, the proposed method restores the missing contact with a jump-like function. The capability of solving contact discontinuities is further improved by minimizing the inherent dissipation term in HLL. Without modifying the original incomplete wave structures of HLL, the robustness for strong shock has been reserved. Thus the proposed method is free from shock instability problem. The accuracy and robustness of the new method are demonstrated through solving several one-and two-dimensional tests. Results indicate that the new formulation based on two-wave HLL-type Riemann solver is not only capable of capturing contact waves more accurately than the original HLL or HLLC but, most importantly, is free form carbuncle instability for strong shock.
Xi Deng, Pierre Boivin, Feng Xiao. A new formulation for two-wave Riemann solver accurate at contact interfaces. Physics of Fluids, 2019, 31 (4), pp.046102. ⟨10.1063/1.5083888⟩. ⟨hal-02100764⟩
Pierre Boivin, M.A. Cannac, O. Le Metayer. A thermodynamic closure for the simulation of multiphase reactive flows. International Journal of Thermal Sciences, 2019, 137, pp.640-649. ⟨hal-01981954⟩ Plus de détails...
A simple thermodynamic closure for the simulation of multiphase reactive flows is presented. It combines a fully explicit thermodynamic closure appropriate for weakly thermal multiphase flow simulations, with the classical variable heat capacity ideal gas thermodynamic closure, commonly used for reactive flows simulations. Each liquid and gas component is assumed to follow the recent Noble-Abel Stiffened Gas equation of state, fully described by a set of five parameters. A new method for setting these parameters is presented and validated through comparisons with NIST references. Comparisons with a well-known cubic equation of state, Soave-Redlich-Kwong, are also included. The Noble-Abel Stiffened-Gas equation of state is then extended as to cope with variable heat capacity, to make the mixture ther-modynamic closure appropriate for multiphase reactive flows.
Pierre Boivin, M.A. Cannac, O. Le Metayer. A thermodynamic closure for the simulation of multiphase reactive flows. International Journal of Thermal Sciences, 2019, 137, pp.640-649. ⟨hal-01981954⟩
Journal: International Journal of Thermal Sciences
Colette Nicoli, Pierre Haldenwang, Bruno Denet. Premixed flame dynamics in presence of mist. Combustion Science and Technology, 2019, 191 (2), pp.197-207. ⟨10.1080/00102202.2018.1453728⟩. ⟨hal-01820207⟩ Plus de détails...
The injection of a water spray within an enclosure prone to explo- sion is reputed to reduce the risk. This strategy for safety improvement is at the root of numerous experiments that have concluded that pre- mixed flame can be extinguished by a sufficient amount of a water aerosol characterized by suitable droplet sizes. On the other hand, certain experiments seemingly indicate that flame speed promotion can be observed when particular water mists are injected within the premixture. To contribute to shed light upon these less than intuitive observa- tions, we propose to study the propagation of a nearly stoichiometric premixed flame within a 2D-lattice of water droplets. Main parameters of investigation are droplet size and droplet inter-distance (or equiva- lently, lattice spacing). When the droplet inter-distance is small, the results confirm that a sufficient amount of water quenches combustion. For larger droplet inter-distance, we observe a flame speed enhance- ment for suitable droplet size. Concomitantly, the flame front folds subjected to Darrieus-Landau instability. The final discussion, which invokes a Sivashinsky-type model equation for DL instability, interprets such a speed promotion in presence of mist as a secondary non-linear enhancement of the flame surface.
Colette Nicoli, Pierre Haldenwang, Bruno Denet. Premixed flame dynamics in presence of mist. Combustion Science and Technology, 2019, 191 (2), pp.197-207. ⟨10.1080/00102202.2018.1453728⟩. ⟨hal-01820207⟩
L. Terrei, A. Lamorlette, Anne Ganteaume. Modelling the fire propagation from the fuel bed to the lower canopy of ornamental species used in wildland–urban interfaces. International Journal of Wildland Fire, 2019, 28 (2), pp.113. ⟨10.1071/WF18090⟩. ⟨hal-02176483⟩ Plus de détails...
South-eastern France is strongly affected by wildfires mostly occurring in the wildland-urban interfaces (WUIs). A WUI fire is often initiated in dead surface fuel, then can propagate to shrubs and trees when the lower canopy is close to (or touches) the ground. Whereas a previous study assessed the fire propagation from the fuel bed to the lower canopy of different species used as ornamental vegetation in this region, the objectives of the current work consisted of checking if the modelling of this fire propagation was possible using WFDS (Wildland-Urban Interface Fire Dynamical Simulator) in comparing experimental and modelling results. Experimental and modelling constraints (i. e. branch geometric definition, branch motion due to convection) showed differences in some of the recorded data (such as time to ignition, ignition temperature, mass loss and maximum temperature), but comparisons of variation in mass loss and temperature over time showed that modelling the fire propagation at the scale of a branch was possible if the branch fuel-moisture content remained lower than 25%. For both experiments and modelling, the ranking of species according to their branch flammability highlighted identical groups of species.
L. Terrei, A. Lamorlette, Anne Ganteaume. Modelling the fire propagation from the fuel bed to the lower canopy of ornamental species used in wildland–urban interfaces. International Journal of Wildland Fire, 2019, 28 (2), pp.113. ⟨10.1071/WF18090⟩. ⟨hal-02176483⟩
Harold Berjamin, Bruno Lombard, Guillaume Chiavassa, Nicolas Favrie. Plane-strain waves in nonlinear elastic solids with softening. Wave Motion, 2019, 89, pp.65-78. ⟨hal-02057946⟩ Plus de détails...
Propagation of elastic waves in damaged media (concrete, rocks) is studied theoretically and numerically. Such materials exhibit a nonlinear behavior, with long-time softening and recovery processes (slow dynamics). A constitutive model combining Murnaghan hyperelasticity with the slow dynamics is considered, where the softening is represented by the evolution of a scalar variable. The equations of motion in the Lagrangian framework are detailed. These equations are rewritten as a nonlinear hyperbolic system of balance laws, which is solved numerically using a finite-volume method with flux limiters. Numerical examples illustrate specific features of nonlinear elastic waves, as well as the effect of the material's softening. In particular, the generation of solitary waves in a periodic layered medium is illustrated numerically.
Harold Berjamin, Bruno Lombard, Guillaume Chiavassa, Nicolas Favrie. Plane-strain waves in nonlinear elastic solids with softening. Wave Motion, 2019, 89, pp.65-78. ⟨hal-02057946⟩
Yongliang Feng, Pierre Boivin, Jérome Jacob, Pierre Sagaut. Hybrid recursive regularized thermal lattice Boltzmann model for high subsonic compressible flows. Journal of Computational Physics, 2019, 394, pp.82-99. ⟨hal-02142837⟩ Plus de détails...
A thermal lattice Boltzmann model with a hybrid recursive regularization (HRR) collision operator is developed on standard lattices for simulation of subsonic and sonic compressible flows without shock. The approach is hybrid: mass and momentum conservation equations are solved using a lattice Boltzmann solver, while the energy conservation is solved under entropy form with a finite volume solver. The defect of Galilean invariance related to Mach number is corrected by the third order equilibrium distribution function , supplemented by an additional correcting term and hybrid recursive regularization. The proposed approach is assessed considering the simulation of i) an isentropic vortex convection, ii) a two dimensional acoustic pulse and iii) non-isothermal Gaussian pulse with Ma number in range of 0 to 1. Numerical simulations demonstrate that the flaw in Galilean invari-ance is effectively eliminated by the compressible HRR model. At last, the compressible laminar flows over flat plate at Ma number of 0.3 and 0.87, Reynolds number of 10 5 are considered to validate the capture of viscous and diffusive effects.
Yongliang Feng, Pierre Boivin, Jérome Jacob, Pierre Sagaut. Hybrid recursive regularized thermal lattice Boltzmann model for high subsonic compressible flows. Journal of Computational Physics, 2019, 394, pp.82-99. ⟨hal-02142837⟩
Nicolas Frangieh, Dominique Morvan, Sofiane Meradji, Gilbert Accary, Oleg Bessonov. Numerical simulation of grassland fires behavior using an implicit physical multiphase model. Fire Safety Journal, 2018, 102, pp.37-47. ⟨10.1016/j.firesaf.2018.06.004⟩. ⟨hal-02114073⟩ Plus de détails...
12 This study reports 3D numerical simulations of the ignition and the propagation of 13 grassland fires. The mathematical model is based on a multiphase formulation and on a 14 homogenization approach that consists in averaging the conservation equations (mass, 15 momentum, energy …) governing the evolution of variables representing the state of the 16 vegetation/atmosphere system, inside a control volume containing both the solid-17 vegetation phase and the surrounding gaseous phase. This preliminary operation results 18 in the introduction of source/sink additional terms representing the interaction between 19 the gaseous phase and the solid-fuel particles. This study was conducted at large scale in 20 grassland because it represents the scale at which the behavior of the fire front presents 21 most similarities with full scale wildfires and also because of the existence of a large 22 number of relatively well controlled experiments performed in Australia and in the 23 United States. The simulations were performed for a tall grass, on a flat terrain, and for 24 six values of the 10-m open wind speed ranged between 1 and 12 m/s. The results are in 25 fairly good agreement with experimental data, with the predictions of operational 26 empirical and semi-empirical models, such as the McArthur model (MK5) in Australia and 27 the Rothermel model (BEHAVE) in USA, as well as with the predictions of other fully 3D 28 physical fire models (FIRETEC and WFDS). The comparison with the literature was 29 mainly based on the estimation of the rate of fire spread (ROS) and of the fire intensity, 30 as well as on the analysis of the fire-front shape. 31 32
Nicolas Frangieh, Dominique Morvan, Sofiane Meradji, Gilbert Accary, Oleg Bessonov. Numerical simulation of grassland fires behavior using an implicit physical multiphase model. Fire Safety Journal, 2018, 102, pp.37-47. ⟨10.1016/j.firesaf.2018.06.004⟩. ⟨hal-02114073⟩
Saptarshi Bhattacharjee, Guillaume Ricciardi, Stéphane Viazzo. LES in a Concentric Annular Pipe: Analysis of Mesh Sensitivity and Wall Pressure Fluctuations. Direct and Large-Eddy Simulation X, pp.93-100, 2018, 978-3-319-63211-7. ⟨hal-02111988⟩ Plus de détails...
Annular pipe flows have varied application in the domains of nuclear reactors, heat exchangers, drilling operations in oil industry etc.
Saptarshi Bhattacharjee, Guillaume Ricciardi, Stéphane Viazzo. LES in a Concentric Annular Pipe: Analysis of Mesh Sensitivity and Wall Pressure Fluctuations. Direct and Large-Eddy Simulation X, pp.93-100, 2018, 978-3-319-63211-7. ⟨hal-02111988⟩
Yongliang Feng, Muhammad Tayyab, Pierre Boivin. A Lattice-Boltzmann model for low-Mach reactive flows. Combustion and Flame, 2018, 196, pp.249 - 254. ⟨10.1016/j.combustflame.2018.06.027⟩. ⟨hal-01832640⟩ Plus de détails...
A new Lattice-Boltzmann model for low-Mach reactive flows is presented. Based on standard lattices, the model is easy to implement, and is the first, to the authors' knowledge, to pass the classical freely propagating flame test case as well as the counterflow diffusion flame, with strains up to extinction. For this presentation, simplified transport properties are considered, each species being assigned a separate Lewis number. In addition, the gas mixture is assumed to be calorically perfect. Comparisons with reference solutions show excellent agreement for mass fraction profiles, flame speed in premixed mixtures, as well as maximum temperature dependence with strain rate in counterflow diffusion flames.
Yongliang Feng, Muhammad Tayyab, Pierre Boivin. A Lattice-Boltzmann model for low-Mach reactive flows. Combustion and Flame, 2018, 196, pp.249 - 254. ⟨10.1016/j.combustflame.2018.06.027⟩. ⟨hal-01832640⟩
Pierre Boivin, Forman A. Williams. Extension of a wide-range three-step hydrogen mechanism to syngas. Combustion and Flame, 2018, 196, pp.85-87. ⟨10.1016/j.combustflame.2018.05.034⟩. ⟨hal-02112081⟩ Plus de détails...
Previously we have shown how a single species X can be introduced, representing either HO 2 for high-temperature ignition or H 2 O 2 for low-temperature ignition, to develop an algorithm that covers the entire range of ignition, flame-propagation, and combustion conditions, without a significant degradation of accuracy, for hydrogen-air systems. By adding relevant CO chemistry to the hydrogen chemistry, this same approach can be applied to derive a comparably useful four-step reduced-chemistry description for syngas blends that have small enough concentrations of methane, other hydrocarbons , or other reactive species to be dominated by the elementary steps of the H 2 /CO system. The present communication reports the resulting extended algorithm. This work begins with the elementary steps of the detailed chemistry as listed in Table 1. We shall employ the numbering of the steps as given in the table, which identifies the 8 steps that are considered to be reversible and gives fitted parameters for the reverses of those steps.
Pierre Boivin, Forman A. Williams. Extension of a wide-range three-step hydrogen mechanism to syngas. Combustion and Flame, 2018, 196, pp.85-87. ⟨10.1016/j.combustflame.2018.05.034⟩. ⟨hal-02112081⟩
Dominique Morvan, Gilbert Accary, Sofiane Meradji, Nicolas Frangieh, Oleg Bessonov. A 3D physical model to study the behavior of vegetation fires at laboratory scale. Fire Safety Journal, 2018, 101, pp.39-52. ⟨10.1016/j.firesaf.2018.08.011⟩. ⟨hal-02114685⟩ Plus de détails...
A 3D multi-physical model referred to as “FireStar3D” has been developed in order to predict the behavior of wildfires at a local scale (<500 m). In the continuity of a previous work limited to 2D configurations, this model consists of solving the conservation equations of the coupled system composed of the vegetation and the surrounding gaseous medium. In particular, the model is able to account explicitly for all the mechanisms of degradation of the vegetation (by drying, pyrolysis, and heterogeneous combustion) and the various interactions between the gas mixture (ambient air + pyrolysis and combustion products) and the vegetation cover such as drag force, heat transfer by convection and radiation, and mass transfer. Compared to previous works, some new features were introduced in the modeling of the surface combustion of charcoal, the calculation of the heat transfer coefficient between the solid fuel particles and the surrounding atmosphere, and many improvements were brought to the numerical method to enable affordable 3D simulations. The partial validation of the model was based on some comparisons with experimental data collected at small scale fires carried out in the Missoula Fire Sciences Lab's wind tunnel, through various solid-fuel layers and in well controlled conditions. A relative good agreement was obtained for most of the simulations that were conducted. A parametric study of the dependence of the rate of spread on the wind speed and on the fuelbed characteristics is presented.
Dominique Morvan, Gilbert Accary, Sofiane Meradji, Nicolas Frangieh, Oleg Bessonov. A 3D physical model to study the behavior of vegetation fires at laboratory scale. Fire Safety Journal, 2018, 101, pp.39-52. ⟨10.1016/j.firesaf.2018.08.011⟩. ⟨hal-02114685⟩
Stéphane Abide, Stéphane Viazzo, Isabelle Raspo, Anthony Randriamampianina. Higher-order compact scheme for high-performance computing of stratified rotating flows. Computers and Fluids, 2018, 174, pp.300-310. ⟨10.1016/j.compfluid.2018.07.016⟩. ⟨hal-02111489⟩ Plus de détails...
To take advantage of modern generation computing hardware, a scalable numerical method, based on higher-order compact scheme, is described to solve rotating stratified flows in cylindrical annular domains. An original approach combining 2d-pencil decomposition and reduced Parallel Diagonal Dominant is proposed to improve the parallelization performance during the computation of Poisson/Helmholtz solvers and time explicit terms. The developed technique is validated with respect to analytical solutions, using the method of manufactured solutions, and available data for two specific configurations. The purpose is to demonstrate its ability to correctly capture the flow characteristics in strato-rotational instability and in baroclinic instability with associated small-scale features. Moreover, this code is found to drastically reduce the huge execution times often preventing detailed numerical investigations of these complex phenomena. Strong scaling test is carried out to assess the performance for up to 1024 cores using grid up to 128 × 568 × 568 in radial, axial and azimuthal directions.
Stéphane Abide, Stéphane Viazzo, Isabelle Raspo, Anthony Randriamampianina. Higher-order compact scheme for high-performance computing of stratified rotating flows. Computers and Fluids, 2018, 174, pp.300-310. ⟨10.1016/j.compfluid.2018.07.016⟩. ⟨hal-02111489⟩
Richard Saurel, François Fraysse, Damien Furfaro, Emmanuel Lapebie. Reprint of: Multiscale multiphase modeling of detonations in condensed energetic materials. Computers and Fluids, 2018, 169, pp.213-229. ⟨10.1016/j.compfluid.2018.03.054⟩. ⟨hal-02115861⟩ Plus de détails...