Optimizing ventricular assist device rotor design parameters through computational fluid dynamics and design of experiments

Heart failure is among the most widespread diseases globally. With the rapid rise in the number of affected individuals and the significant disparity between organ demand and supply, the relevance of implantable devices has grown each year. However, these devices face various regulatory restrictions, and obtaining approval requires outstanding performance. This paper focuses on optimizing the design parameters of a rotor for an axial flow ventricular assist device (VAD) currently under development. The parameters investigated include splitters, inlet blade angle, outlet blade angle, blade count, rotational speed, clearance gap, blade thickness, and rotor length. The study aims to maximize pressure rise and hydraulic efficiency while minimizing the torque required to drive the rotor. The D-optimal method was employed to create an experimental design for the simulations. By comparing R², adjusted R², and RMS error across different regression models, the quadratic regression model emerged as the most effective for deriving a suitable mathematical model from the numerical results. The validity of these models was confirmed through the consistency between predicted and observed outcomes.