PERFORMANCE CHARACTERIZATION AND CFD ANALYSIS OF AN AXIAL BLOOD PUMP

Abstract

This paper describes the performance characterization of an axial blood pump that is developed in our laboratory. Using computational fluid dynamics (CFD), regions of flow separation and high shear stress were identified since they are of concern in the development of cardiac assist devices. CFD is an efficient and cost effective tool in assisting the designer to reduce the number of experimental trials needed. Preliminary CFD studies showed the existence of substantial backflow in the impeller passage. The impeller geometry was improved using CFD modeling. Regions of flow separation were eliminated while regions of scalar stress of up to 150 Pa were observed near to the impeller tip. The final prototype can deliver a flow rate of 5 L/min at a pressure head of 14 kPa when operating at a speed of 10,000 rpm. The model was fabricated using rapid prototyping techniques and performance characterization of the pump has demonstrated that the CFD prediction of the pump performance curve and the pressure developed along the impeller agrees reasonably well with experimental results.