Numerical investigation of the pump flow in an automotive torque converter

This paper addresses the fundamental flow feature question of how to design and optimize torque converter blades with numerical analysis. The present numerical analysis describes the details of the incompressible, three-dimensional, viscous and turbulent flow field within the pump of an automotive torque converter. An advanced Navier-Stoked flow code was modified for computations of the torque converter flow with the mixing plane and the k-ε turbulence models. The pump blade tip in our analysis is bent backward to meet the performance characteristics. The present numerical results assess the development of jet/wake flow and secondary flow along the flow direction. It is of note that the direction of the secondary flow at pump exit has not been changed. Undesirable pressure distributions near the exit were seen, mainly as a result of tip bending at the pump exit. The firm understanding of the flow details and performance characteristics provided by CFD analyses makes it possible to design highly efficient torque converters with optimized blade geometries.