3-DIMENSIONAL NUMERICAL AND EXPERIMENTAL STUDIES TO MODEL ARTIFICIAL HEART VALVES HEMODYNAMICS

Abstract

The characterization of the artificial heart valves flow fields is a crucial step to evaluate the performances on improving heart valve engineering. With the advancement of Computational Fluid Dynamics, we are able to study the complex hemodynamics in details such as stagnation, recirculation zones and shear stresses. In this research, we established a numerical model using arbitrary Lagrangian Eulerien to study the hemodynamic performance of a bileaflet mechanical heart valve. The 3-dimensional numerical simulation was performed using OpenFOAM, and validated experimentally for both laminar and pulsatile flows. We investigated how different aortic sinus shape, the downstream aortic arch geometry and the location of the hinge recess, can influence the flow fields in the hinge regions. The effects of implantation angles of bileaflet mechanical heart valves on the sinus region and downstream flow profiles were also investigated. Subsequently, comparisons between the flow of bileaflet and trileaflet mechanical heart valves were made, followed by the effect of implantation angles of trileaflet mechanical heart valves on the downstream flow profiles. Finally we took into account the continuous and full interaction between the blood flow and the valve leaflets, using Fluid Structure Interaction to investigate the flow through a bileaflet mechanical heart valve and compared with the prescribed results. This research aims to provide a more accurate representation to study the hemodynamic parameters of artificial heart valves.