A comparison study of cavitating flow ina ventricular assist device using laminar and turbulent model

Abstract

In the present study, the cavitating flow phenomena due to the valve closure in a ventricular assist device were computationally studied. Both laminar flow and turbulent flow were computed and compared with each other. For computations, a dynamic mesh strategy to cope with the movement of the valve was developed. The simulation of cavitation was carried out with the full cavitation model which took considerations of the first-order effect of the formation and transport of vapor bubbles, the turbulent fluctuations of pressure and velocity, and the magnitude of non-condensable gases. The turbulent flow was computed by using the κ-ω model. The results show that the local turbulence is one of the vital effects on the development of the cavitating flow. The maximum velocity at the moments of valve closing was significantly reduced in the turbulent flow modeling. Turbulence reduces the jet intensity at the valve closure and, hence, the cavitating region on the valve.