Application of slotted blade in the improvement of turbomachinery performance

Flow separation is ubiquitous in turbomachinery. Compared with the more mature turbomachinery flow separation control method where the medium is gas, the turbomachinery flow separation method where the medium is liquid cannot be controlled well. In this study, according to the flow separation control principle of the aircraft fowler flap, taking the stator blade of the hydraulic torque converter as the basic research object, the stator blade shape is fitted with Joukowsky transformation, and then it is slotted. Computational fluid dynamics is used to perform flow analysis on original blades and slotted blades. It is found that compared with that of the original blade, the slotted blade’s flow separation phenomenon is effectively suppressed, turbulent kinetic energy is reduced, flow is more stable, and energy loss is reduced. In addition, using slotted blades for torque converter simulation, the torque ratio is increased by up to 0.245, and the efficiency is increased by up to 5%, which shows that slotted blades can improve the mechanical performance of the pump wheel and are not limited to the torque converter.