A computer method for simulation of cardiovascular flow fields: Validation of approach

Abstract

An existing pressure correction method to model unsteady flow with arbitrarily moving boundaries has been adapted to simulate three-dimensional blood flow in compliant vessels. This noniterative method, which is first-order time accurate, solves the three-dimensional unsteady Navier-Stokes equations with arbitrarily moving boundaries for the no slip boundary condition. It is capable of realistically modeling blood flow in the heart, since it allows the simulation of both passive tissue (e.g., heart valves) and active tissue (e.g., heart muscle fibers). The boundaries, which represent cardiovascular tissue, are displaced by the fluid motion. When they are moved, the boundaries have the ability to exert a force which opposes fluid motion. The force the boundary exerts is assumed to be proportional to strain. The results of simulating 3D pulsatile flow through a flexible tube are presented, as well as a comparison to Womersley's analytic approximate solution for axisymmetric pulsatile flow in a flexible tube. © 1992.