Computational modeling of the interactions of thrombi as a deformable body
Given the current rate of cerebral thromboembolism in the ventricular assist device (VAD) patient population, the
computational study of the interaction of thrombi as deformable bodies will be targeted as the main aim of the current study. It should be noted that, in most studies, elastic collisions between thrombi and arterial walls were assumed with the coefficient of restitution (COR) set to unity, while some previous experimental studies indicated a wall-thrombus 0.5 < COR < 1. Therefore, a fully-coupled Eulerian Volume-of-Fluid (VOF) closed-loop computational model is devised to study the behavior of thrombi. In this study, the contact angle forming during the surface wetting process is not pre-defined as a boundary condition, while the advancing and receding
equilibrium contact angles are only required to define the wetting properties of liquid phase interacting with the solid surface. The advantage of this computational approach is implementing a dynamic contact angle that is derived implicitly by the fluid flow characteristics and the physics applied on the surface interfaces. The results are validated against previously reported experimental data of normal water droplets impingement on dry surfaces. It is concluded that this computational method is an effective approach for the multiphase flow analysis of droplet interactions with surfaces without a pre-defined contact angle law that can lead to only approximate solutions for these problems.