EXPERIMENTAL AND NUMERICAL DETERMINATION OF THE PERFORMANCE OF HEART ASSIST PUMP USING A NON-NEWTONIAN FLUID

Heart failure, which has an important place in heart diseases, is a health condition that human heart cannot pump enough blood for various reasons. Mechanical systems called ventricular assist devices (VADs) have been developed to assist individiuals with this disease. Left ventricular assist devices help blood to be pumped from the left ventricle to the aorta. In this study, the hydrodynamic performance of a mixed flow left ventricular heart assist pump was determined by the computational fluid dynamics (CFD) method. In the analysis, the working fluid was used a non-newtonian mixture of water and xanthan solution (by mass 0,06% xanthan gum) which has similar rheological properties to blood, was used as the working fluid. Performance curves of pressure, flow and efficiency of the pump were obtained at rotational speeds of 5000, 6000 and 7000 rpm. In order to compare the results, CFD analysis are repeated with a Newtonian fluid, water glycerin solution (by volume 40% glycerin and 60% water). According to the numerical performance results of the pump, it was seen that the pressure difference between two fluids at high rotational speed and low flow rates is 9,2% and high flow rate it is decreased to about 7%. The pump reached a pressure value of 88,33mmHg at a rotation spxeed of 5000 rpm at 5L/ min. At this working point, the pump hydraulic efficiency was determined as 52,74%