Numerical and Experimental Investigation of A Centrifugal Heart Assist Pump Prototype

In this study, pump characteristics of a prototype centrifugal ventricular assist pump, which is designed with conventional design method of large scale pumps, have been determined by CFD software and these characteristics are confirmed experimentally. Also shear stresses on the walls of the pump were inspected with CFD simulations. As design parameters; 5 L/min flow rate, 3000 rpm motor speed and 100 mm-Hg pressure rise have been selected. Solid model of the designed pump was prepared and manufactured by rapid prototyping machine. Volute of the pump was manufactured from aluminum block at CNC milling machine. At performance tests of the pump, water and 40% glycerin-60%water solution, which have similar rheological properties with blood, were used as working fluid. At design speed and flow rate, 72 mm-Hg of pressure rise has been obtained. For tests which water used as fluid, a fine agreement between CFD determined and experimental pump performance results has been seen. For tests which water-glycerin solution used as fluid, there is nearly 15% of deviation between CFD determined and experimental pump performance results. At CFD simulations shear stress value for water was 664.7 Pa and 1271 Pa for glycerin solution. Upcoming researches will be focused on decreasing this shear stress level.