The mutual influence and blade-row interaction between pump and turbine in a hydrodynamic torque converter

Abstract

In this paper the results of a numerical calculation of the unsteady flow inside a one-stage two-phase automotive torque converter will be presented. For the investigation the finite volume method has been employed. The commercial 3D Navier-Stokes Software CFX of ANSYS Inc. was used for the flow simulation. Here the incompressible Reynolds-Averaged-Navier-Stokes (RANS) equations will be solved using the k-[epsilon] turbulence model. The flow field is determined by the blade position of both rotors, which have different rotating velocities. Whenever two adjacent blade rows at different speed, unsteady interactions occurs in the flow. The unsteady flow at the pump exit and turbine inlet will be analyzed through instantaneous flow fields in a period so that the rotor-rotor interaction can be in detail understood. The inlet flow of the turbine was markedly periodic and influenced by the pump jet/wake. In contras the pump outlet flow showed a little dependence on the turbine relative position.