NUMERICAL INVESTIGATIONS OF A CENTRIFUGAL BLOOD PUMP

This paper presents computational fluid dynamics (CFD) studies of a centrifugal blood pump. 3-D models of five different blade geometries are investigated numerically using CFX-TASCflow. The impellers were designed using an inverse design technique where the swirl distributions were prescribed. The results showed the flow in the impeller passages is highly dependent on the impeller blade profiles. The flow in the radial blade impeller is unsatisfactory as flow separates at the leading edge of the suction side. Flow is confined mainly to the pressure side. Design 2, with an inlet angle of 6.7 degrees and outlet angle of 30 degrees, offers the greatest potential as only a small region of flow reversal is detected. Further optimization is necessary to completely eliminate regions of flow reversals. The highest scalar shear stress in both designs is 240 Pa and 120 Pa respectively. In addition, this paper demonstrates that the use of inverse design can help the designer to better design and analyze the flow field in centrifugal blood pumps.