Effects of non-Newtonian fluid on centrifugal blood pump performance

A 2:1 scaled-up model of the Kyoto-NTN magnetically suspended impeller centrifugal blood pump developed by Kyoto University, Japan, is tested using aqueous Xanthan gum solution and water as working fluids, respectively. It is found that the pump head rise with the solution is lower than that with water at same flow rate when the pump operates at low rotor speeds; at high rotor speeds, however, the pump will generate a higher head for the solution than for water at the same flow rate, and a maximum difference of 7% is detected. Data comparison indicates that water does not accurately model the head vs. flow rate characteristics of the prototype pump, and aqueous Xanthan gum solution of 600 ppm produced results best simulating the performance of the prototype pump.