Numerical study of a centrifugal blood pump with different impeller profiles.

Computational fluid dynamic simulations of the Kyoto-NTN magnetically suspended centrifugal blood pump with 16 forward-bending blades (16FB), 16 straight blades (16SB), and eight backward-bending blades (8BB) impellers were performed in this study. Commercial CFD software package FLUENT were used as the solver. The purpose of this study is to find out how the impeller blade profiles affect the inner flow and the performance of the centrifugal blood pump. The simulations were carried out with the same impeller rotating speed of 2,000 rpm and pump flow rate of 5 L/min to compare the three pump models. It was found that the 16SB impeller can produce higher pressure head than the 16FB and 8BB impellers under the same impeller rotating speed and pump flow rate. The flow particle tracing was carried out to estimate the blood damage level caused by the three different impeller profiles. It was found that the 16FB and 8BB models have caused the highest and lowest blood damage, respectively. The 16SB is recommended among the three pumps because it can generate the highest pressure head and induce mild blood damage index, although it was higher than that of the 8BB model.