A Mixed Flow Heart Assist Pump Design and Investigation of Its Performance Using Computational Fluid Dynamics

Heart failure is a heart disease in which the heart cannot pump enough blood to meet the body’s needs. Left ventricular heart assist pumps help to pump the blood from the left ventricle of the heart to the aorta artery. In this study, the design of a helico-centrifugal mixed-flow heart assist pump was made using the pump design programs. The hydrodynamic performance of the pump was determined by the computational fluid dynamics (CFD) method. Using the pump s numerical performance results, the optimum pump design was performed according to the hydraulic efficiency. Pressure, flow rate and power consumption of pump at different rotational speeds were measured in the experimental setup and experimental hydrodynamic performance curves were determined with these measured values. In the experiment and CFD analysis, the working fluid was a water-glycerin solution (by volume 40% glycerin and 60% water) which has the same viscosity as blood. Also, for comparison; experiments and CFD analysis were performed with water. According to the experimental and numerical performance results of the pump, the deviation ratio of the pressure difference was calculated to be less than 1% at high flow rates and approximately 5.7% at low flow rates. The pressure of 100 mmHg at 5 L / min flow rate, which must be provide by the adults heart assist pumps was achieved at rotation speed of 5100 rpm. At this point, the hydraulic and overall efficiency of the pump and the maximum wall shear stress in the pump was determined to be the 52.1%, 30.9% and 166 Pa, respectively.