Numerical simulation on two-phase blood flow in a helical tube

Objective: The classic single phase Newtonian blood flow model ignores the interaction of red blood cells (RBCs) with plasma or the shear-thinning behavior of blood. Therefore, a multiphase non-Newtonian model was adopted to study hemodynamic parameters in coronary artery model. Methods: The blood was considered as a mixture of RBCs and plasma. A helical tube was adopted to simulate the coronary artery. The movement of RBCs and the distribution of RBC volume fraction in coronary artery were analyzed, and the simulation results were compared with those by single-phase non-Newtonian blood model. Results: The average wall shear stress (WSS) values obtained by the two models were close. But obvious RBC aggregation was observed on the inside wall of the underside of helical tube in the two-phase flow simulation, with low WSS distributions. Conclusions: Hemodynamic parameters of the helical tube were obtained by multiphase flow simulation, and RBC aggregation were observed on the inside wall of the model. Accordingly it was concluded that the inside wall of coronary artery might be more prone to thrombosis, which is in consistent with the clinical observations. This study may help to elucidate the pathogenesis mechanism of atherosclerotic lesions.