Toward a better understanding of the link between vasculature structure and function - insights from cellular blood flow simulations in complex geometries

Abstract: Blood-related diseases affect millions of people each year. Some of these diseases (such as malaria or sickle-cell anaemia) change the properties of red blood cells (RBCs), while others (such as cancer) can lead to an altered vascular structure. In all these cases, the function of organs and vascular transport are affected to some degree. In order to develop more effective treatment options, we need to understand better how vascular structure and function are related. One key question to answer is how RBCs distribute at diverging vessel bifurcations under various conditions, which determines the overall perfusion of any vascular network. Blood flow simulations with resolved RBCs can shed light on processes that are difficult to measure in experiments and help make accurate predictions. In this talk, I will show how we use the HemeLB code to simulate resolved RBCs in realistic microvascular geometries. The RBCs are approximated by hyperelastic biconcave disks suspended in a Newtonian liquid. The lattice-Boltzmann method is used to solve the Navier-Stokes equation, a finite-element method captures the elastic behaviour of the RBCs, and the immersed-boundary method is used for the full coupling of fluid and cell dynamics. I will present two relevant case studies: 1) the distribution of RBCs at single diverging bifurcations under the influence of the RBCs lingering at the bifurcation apex and 2) the association between RBC motion in and the development of a retinal network. This talk highlights the great potential of experimental-numerical synergies, helps define the open challenges in microvascular blood flow research, and enables researchers solving these important problems.

Bio: Timm Krüger is Professor of Fluid and Suspension Dynamics in the School of Engineering at the University of Edinburgh. He is Head of the Institute for Multiscale Thermofluids. Timm obtained his PhD in Physics from Bochum University in 2011. After postdoctoral positions in Eindhoven and London, he became a Chancellor's Fellow at the University of Edinburgh in 2013 where has been working since. Timm enjoys doing interdisciplinary research bringing together experimentalists and modellers.