EXPERIMENTAL INVESTIGATION OF STEADY AND UNSTEADY FLOW FIELD UPSTREAM AND DOWNSTREAM OF AN AUTOMOTIVE TORQUE CONVERTER PUMP

摘要

The objective of this investigation is to understand the steady andthe unsteady flow field at the exit of an automotive torque converterpump with a view towards improving its performance. Themeasurements were conducted in a stationary frame of referenceusing a high frequency response five-hole probe and the data wereprocessed to derive the flow properties in the relative (pump) frameof reference. The experimental data were processed at three differentoperating conditions: maximum efficiency point, design point andnear-stall point. The unsteady values of flow properties (pressure,velocity and flow angles) were divided into five components: mean,periodic, blade aperiodic, revolution aperiodic and unresolvedcomponents.The velocity profiles indicate zones of separation near the coreregion at speed ratio 0.8. This zone is transported to the shell regionat speed ratio 0.065 due to the presence of a strong secondaryvortex. The secondary vortex (weak) for the speed ratio 0.8 rotatesanti-clockwise, and is located only near core-wake region. Thesecondary vortex (strong) at speed ratio 0.065 rotates clockwise,and encompasses the entire passage. The unsteady flow data showthat unresolved and periodic components dominate the unsteadinessat the pump exit. The overall aperiodicity is negligible and isdominated by the blade aperiodic component.