Comparative Analysis of SPH and FVM Numerical Simulations of Bloodflow through Left Ventricle

Abstract

The purpose of this research was to compare blood flow modeling inside the heart’s left ventricle using commercial smoothed particle hydrodynamics (SPH) and finite volume method (FVM) solvers. These two methods are both based on continuum mechanics, and while FVM uses Eulerian material framework, SPH uses a Lagrangian formulation. In this study, the focus was only on CFD analysis of blood flow through the left ventricle using the two mentioned methods. Therefore, in the numerical analysis using FVM, walls were modeled as boundary conditions where fluid velocity was set to zero. The ventricle wall in the SPH was modeled using larger, fixed fluid particles, so at this point, there is no need for a specific contact definition. LS-DYNA software was used for modeling the left ventricle using the SPH method. In order to generate realistic fluid flow injection particles at the mitral valve and deactivation planes at the aortic semilunar valve were used where particle velocity was defined by time functions. Ansys Fluent software was used for modeling the left ventricle using FVM, within which a finite volume mesh was generated. Velocities at the inlet and outlet of the model are defined by functions using User Defined Function (UDF) so that the fluid flow corresponds to the realistic blood flow through the left ventricle. The results obtained by FVM were used as a verification of the results obtained using the SPH method. In the results section of the paper, the velocity field obtained by SPH and FVM methods is shown and compared. SPH offers greater possibilities to study FSI phenomena like the effects of wall deformations, or tracking the movement of solid particle inclusion, all within the single numerical domain. On the other hand, it requires elaborate contact definition, and prolonged analysis time in comparison to the finite volume CFD analysis.