Development of a centrifugal blood pump with magnetically suspended impeller and the related fluid mechanical problems

This paper deals with fluid mechanical problems encountered in eight years of developmental studies on a centrifugal blood pump with magnetically susp ended impeller. The main results of the investigation are as follows. The i mpeller disk friction is dominant among all the power losses; the magnetica lly suspended impeller with radial straight vanes is the most stable. Motor current depends on blood viscosity and flow rate. Consequently, the flow r ate and pressure difference can be estimated by self-sensing without any ne ed for flowmeter and pressure transducers.