Experimental investigation of flow through a bileaflet mechanical heart valve

Turbulent flow downstream of a bileaflet mechanical heart valve is investigated using digital particle image velocimetry. Evolution of flow structures during the systole and diastole phases of a typical cardiac cycle is characterized by obtaining global flow velocity measurements in multiple cross-sections of the flow field. Instantaneous and time-averaged patterns of flow velocity, vorticity, and streamline topology are used to illustrate the interaction between the unsteady vortices that results in elevation of shear stress levels. This imagebased approach can potentially lead to the development of methods for the control of platelet activation and provides insight into the underlying flow physics.