Can the DPD numerical method simulate blood flow?

Abstract

Dissipative Particle Dynamics (DPD) is a powerful numerical method normally used to simulate compressible flows. Blood, however, is a multi-component, multiphase incompressible fluid. We investigate whether the DPD method can also be utilized to analyze incompressible flows using a benchmark flow system of a fluid moving inside a rotating cylinder. We observed that if the parameters controlling the DPD method are not judicially selected the Dissipative Particles (DP's) tend to accumulate at the boundary, leaving the cylinder's core empty of DP's, an obvious aphysical result. In the past it was suggested to strongly increase the conservative repulsive force between DP's. It required an associated diminution of the time step, which in turn, led to extremely long prohibitive computation time. We suggest a novel approach to circumvent this problem by adjusting the value of the cutoff radius (which determines the radius of influence of a DP particle) to twice the mean distance between adjacent DP's.