2D Numerical simulation for unsteady flow through mechanical heart valve using COMSOL

In this work, I present a 2D numerical simulation model for the unsteady flow through Bi-leaflet Mechanical Heart Valve (MHV) using Fluid-Structure Interaction (FSI) solver implemented in COMSOL Multiphysics software. The MHV dimensions are matching St Jude Regent design. The aortic root along with the sinus cavities are modeled to mimic the mitral valve opening to the aorta using quadratic Bézier function. The ventricular and the aortic pressure wave forms during the systole and diastole cycles are used as the inlet and outlet boundary conditions mimicking the pressure driven fluid conditions. A fully coupled Arbitrary Lagrangian- Eulerian (ALE) method is applied to solver settings to account for the two-way interaction between the fluid (blood) and the solid (MHV leaflets). Moreover, a physics-controlled extra fine mesh was used. Mesh sensitivity analysis was carried to demonstrate the quality of the mesh. Velocity profile at different time instants in the systolic-diastolic cycle are reported to demonstrate the velocity field at mid-opening, full-opening, mid-closing and fully closed MHV positions. The leaflet angle versus time is also simulated. Lastly the shear rate around the hinges is reported. Non-Newtonian blood model is attempted and a comparison between the unsteady behavior of the blood flow under laminar and turbulent flow conditions is also summarized.