Fuzzy Logic-Based Modeling and Multi-Objective Optimization of Blood Pump Rotational Speed Considering Hydraulic and Hemolytic Performance

This study aims to determine the optimal operating rotational speed of a centrifugal blood pump. In order to investigate this, a centrifugal blood pump was designed, and its hydraulic efficiency and hemolysis index were calculated using computational fluid dynamics (CFD) simulations over a range of 2500-3500 rpm for rotational speed and 2.5-6 L/min for flow rate. The pump design was carried out by considering key geometric parameters, including the number of blades, inlet and outlet widths, inlet and outlet angles, impeller diameter, volute inlet width, and volute outlet diameter. Subsequently, a fuzzy logic-based pump model was developed using rotational speed and mass flow rate as input parameters, and pressure difference, hemolysis index, and hydraulic efficiency as output parameters. After validating this model with CFD simulations, the optimal pump rotational speed was determined by solving an objective function incorporating hydraulic efficiency and hemolysis index using the particle swarm optimization (PSO) algorithm. The results indicate that the optimal rotational speed of the centrifugal pump is 3150 rpm, at which a hydraulic efficiency of 36% and a hemolysis index (HI) of 1.65x10-5 are achieved. In summary, this study presents a systematic methodology for determining the optimal operating speed that enables centrifugal blood pumps to operate efficiently while maintaining a low hemolysis index.