Computational Fluid Dynamic Analysis of a Blood Pump: An FDA Critical Path Initiative

Abstract

Computational Fluid Dynamics (CFD) has become a routine tool in recent times for use in blood-contacting medical device design and analysis, such as prosthetic heart valves and ventricular assist devices (VADs). While CFD can aid in design by decreasing the need for expensive prototyping and iterative laboratory testing, standardizations are not currently available for CFD to be used for medical device safety analysis at the preclinical stage. To address this, the U.S. Food and Drug Administration (FDA)’s Center of Devices and Radiological Health (CDRH) has sponsored CFD “round-robins.” This paper focuses on Computational Round Robin #2 – Model Blood Pump. The exact geometries, flow conditions and fluid characteristics for the CFD analysis have been supplied to the participants. In the CFD analysis presented in this paper, a rotating fluid zone around the pump impeller was used to avoid the complexities of a dynamic mesh. The rotating fluid zone was modeled by including the centrifugal and Coriolis forces in the Navier-Stokes equations. The Shear Stress Transport (SST) k-ω turbulence model was used and the steady-state solutions for the desired flow conditions were calculated. Current experimental data is still being collected by FDA for the flow conditions given in the study. However, some of the pump operating characteristics are available from work of other investigators and are used to validate the CFD results.