Streamlined design of impeller and its effect on pump haemolysis

To investigate the effect of impeller design on pump haemolysis, five impellers with different numbers of vanes or different vane angles were manufactured and tested in one pump for haemolysis comparison. The impellers had the same dimension and logarithmic spiral vane form that coincided with the stream surfaces in the pump, according to an analytical and three-dimensional design method developed by the authors. Consequently, an impeller with six vanes and a 30 degrees vane angle had the lowest haemolysis index. The result agrees with the theoretical analyses of other investigators searching for the optimal vane number and vane angle to achieve the highest efficiency of the pump.