FEM Analysis Of Venous Valve Using Time-Dependent And Spatially-Varying Pressure Distributions Obtained From FSI Simulations

Venous valves in deep veins are susceptible to diseases such as deep vein thrombosis (DVT), chronic venous insufficiency, and varicose veins. Therefore, it is important to investigate the behavior of the valve and the stress distribution across it during its operation. Even though fluid–structure interaction (FSI) is a compelling computational method involving how fluids and structures influence each other and can predict their coupled behavior, studies on structural analysis of venous valves have been gained less attention in the literature since these valves, unlike heart valves, do not operate under high pressures, and there is limited information on the boundary conditions, making structural analysis more challenging. In this study, first, we conducted a transient FSI simulation to obtain time-dependent and spatially varying loads on the valve leaflets, namely static pressure, dynamic pressure, and wall shear stresses. Then, these flow-induced loads were extracted at each time step and applied as transient and localized boundary conditions in a stand-alone finite element analysis (FEA). Unlike most existing studies that apply a single scalar pressure across the valve surface, our approach applies distinct node-by-node values, capturing a non-uniform pressure distribution. This additional structural model allowed us to isolate and investigate the valve’s mechanical response to different flow components in greater detail. The results indicated that deformation varied depending on the type of boundary conditions, as well as the opening-closing mechanism and stress distribution. This highlighted the impact of each applied component on the valve's surface due to the surrounding blood flow.