Steady and Unsteady Flow Field at Pump and Turbine Exits of a Torque Converter

Abstract

The steady and unsteady flow field at the pump and the turbine exit of a 245 mm diameter automotive torque converter was measured by a miniature high-frequency-response five-hole probe and a high-frequency-response total pressure Pitot probe in the stationary reference frame. The data were decomposed into blade periodic, blade aperiodic, and unresolved unsteady components. The periodic flow data shows that the pump exit flow has four major zones; the free-stream flow, the blade wake flow, the core-suction corner separation flow, and the mixing zone. The unsteady flow data shows that the unsteadiness in the free-stream is uniform, and the unsteadiness in the wake mixing flow zone is very high. The turbine exit flow is almost fully developed at the measurement plane, the flow field is uniform in the tangential direction, and only radial gradients in flow properties exist. A region of separated flow with high unsteadiness and high axial component of vorticity was observed at the measurement plane near the core.