Laser Velocimeter Measurements in the Stator of an Automotive Torque Converter

Abstract

The flow field in the stator of a clear torque converter was studied using laser velocimetry. Five planes in the stator were studied at a speed ratio of 0.800 and three planes were studied at a speed ratio of 0.065. Data complements previously available pump and turbine data. Flow in the stator inlet plane is highly non‐uniform due to the complicated flow exiting the turbine. At the 0.800 speed ratio, separation regions are located in the 1/4 and mid‐planes in the corepressure corner region. In the 3/4 and exit planes, separation regions are located in the shellsuction corner. In the inlet plane a region of high velocities is located along the shell near the pressure side for a speed ratio of 0.800. The high velocity region migrated to the shell‐suction corner and suction side in the 1/4 and mid‐planes. The overall velocity field for the speed ratio of 0.065 changes significantly from the inlet plane to the mid‐plane. The velocity magnitude generally decreases from the suction to the pressure side of the inlet plane and the general direction of the tangential velocity is from pressure‐to‐suction surface. At the speed ratio of 0.065 a strong secondary flow in the inlet from suction surface to pressure surface was seen. However, at the high speed ratio a moderate secondary flow in the inlet from pressure surface to suction surface was observed. Mass flow rates at the different planes are within the experimental uncertainty and also within the uncertainty of pump and turbine mass flow rates. The flow in the stator inlet plane are significantly influenced by the turbine relative blade position. The turbine influence on the mid‐plane data is significantly less than on the inlet plane data. The influence of the pump blade position on the stator exit plane is small.