[Effect of impeller vane number and angles on pump hemolysis]

To evaluate the effect of impeller design on pump hemolysis, five impellers with different number of vanes or different vane angles were manufactured and tested in one pump for hemolysis comparison. The impellers are made to have the same dimension and same logarithmic spiral vane from which coincide with the stream surfaces in the pump, according to the analytical and three-dimensional design method developed by the authors. Consequently, an impeller with 6 vanes and 30 degrees vane angle has the lowest hemolysis index. This result agrees with the theoretical analyses of other investigators searching optimal number of vanes and vane angle to achieve the highest efficiency of the pump.