Characteristics of transient blood flow in MHVs with different maximum opening angles using fluid-structure interaction method

A numerical analysis has been performed to investigate the characteristics of two-dimensional transient blood flows interacting with the leaflet motio n in a bileaflet mechanical heart valve with different maximum opening angl es, located in the aortic position. Here, for one cycle of heartbeat the an alysis has been carried out in the light of fluid-structure interaction sin ce the blood flow and the leaflet motion are coupled with each other. Blood has been assumed to be a Newtonian and non-Newtonian fluid, where the Carr eau model has been used for the simulation of non-Newtonian fluid. Physiolo gic ventricular and aortic pressure waveforms have been used as flow bounda ry conditions at the ventricle and the aorta. A finite volume computational fluid dynamics code and a finite element structure dynamics code have been used concurrently to solve the flow and the structure equations, respectiv ely, where the two equations are strongly coupled. Flow fields, leaflet beh avior, and shear stresses with time have been obtained. Also the discharge and the regurgitation flow rates have been calculated. The maximum shear st ress, an important issue for valve hemodynamic analysis, has been found in the vicinity of the contact point where a leaflet contacts with housing in the final stage of the closing phase.