NUMERICAL SIMULATION ON SOLID–LIQUID MULTIPHASE FLOW INCLUDING COMPLEX-SHAPED OBJECTS WITH COLLISION AND ADHESION EFFECTS USING IMMERSED BOUNDARY METHOD
Free (open access)
Volume 6 (2018), Issue 1
162 - 175
MAMORU HOSAKA, TAKAYUKI NAGATA, SHUN TAKAHASHI & KOTA FUKUDA
This study was devoted to investigate the interaction between platelets and blood cells in a blood plasma by using computational fluid dynamics (CFD). In this study, we developed a flow solver to solve the two-dimensional incompressible solid–liquid multiphase flow including collision and adhesion effects. This solver is based on equally-spaced Cartesian mesh and immersed boundary method (IBM) to represent the platelets and red blood cells including the interaction. We proposed a new adhesion algorithm to simulate the collision and interaction of the platelet–platelet and platelet–blood vessel. This adhesive strength determined by Kelvin Voigt model is enforced on the immersed boundary. In addition, we introduced a collision algorithm for complex-shaped object to analyze the flow including real blood cells. In the previous study by Kamada et al. , the moving particle semi-implicit (MPS) method was adopted to simulate the behaviour of blood plasma, platelets and red blood cells. From this study, it was confirmed that the number of adhesion platelet increases with the value of shear rate at the wall. Then, in this study, we analyzed the solid–liquid multiphase channel flow to confirm the deposit of the platelet. The channel flow including an obstacle of a medical stent and the moving cylinders of platelets was investigated for the comparison with the previous study. The Reynolds number based on the channel height was set to be between 5 and 50. As results, we confirmed that the platelets adhere to the wall due to the separation and vortex generation behind the obstacle. The influence of the vortex became more effective with increasing the Reynolds number.
adhesion, collision, IBM, particle-laden channel flow, platelet, red blood cell, solid–liquid multiphase flow