Tatsuo Takano

MICROSCOPIC-SCALE SIMULATION OF BLOOD FLOW USING SPH METHOD

We have developed a microscopic blood model based on the Smoothed Particle Hydrodynamics (SPH) method. In the model, plasma fluid is discretized by SPH particles, and a red blood cell (RBC) is expressed by internal SPH particles surrounded by elastic membrane particles. For verifying the model, we numerically analyzed two popular phenomena of blood flow. One is the tank-tread motion of an RBC under a constant shear field. The numerical results are agreed well with the experimental data and the tank-tread motion of RBC is well reproduced. The other is the axial migration or pinch effect of RBCs in Poiseuille flow. From the numerical results, we find that the axial migration effect becomes weaker as the viscosity of cell internal fluid becomes higher. The reason is because the RBC motion changes from tank-tread motion to rigid body rotation (from axial migration effect to pinch effect) as the cell contents become thick. From these results, it is confirmed that our blood model based on the SPH method can well express microscopic and rheological properties of RBCs.