Analysis of Influence of Stator Blade Outlet Angle on Performance of Torque Converter

doi:10.3901/JME.2024.11.105

Abstract

Abstract: Torque converter stator blade angle optimization is an important and economical design solution to improve its performance. Based on computational fluid dynamics, the flow field of the torque converter is simulated numerically and the external characteristics are predicted. The three-dimensional vortex system structure of the stator channel is reconstructed and the two-dimensional cross section velocity field and vorticity field are extracted. Through qualitative and quantitative comparative analysis of the internal/external characteristics, the influence law of the change of the stator blade outlet angle on the performance of the torque converter is revealed. The results show as follows: ① Under low speed ratio conditions, when the stator blade outlet angle is reduced, the torque ratio is basically unchanged, and the torque coefficient of the pump is significantly reduced, especially in the angle variation range of 28°-22°; ② Liquid flow impacts the head of the stator blade to form a cylindrical flow around it. As the stator blade outlet angle decreases, the continuity of the flow around the cylinder is strengthened, and the curvature radius gradually decreases. The blade pressure surface attachment vortex is stretched and deformed, and the blade suction surface long vortex gradually moves toward the middle of the flow channel. When the outlet angle is 20°, it gathers with the attached vortex, and the energy accumulates, causing the jet flow rate at the tail of the blade to increase. The multi-scale vortex carrying energy is torn and collided, and the vortex shedding phenomenon is intensified. ③ Reducing the stator blade outlet angle causes the inlet flow rate of the pump to increase, resulting in the reduction of the pump torque, resulting in the reduction of the pump torque coefficient. Based on the analysis of flow field structure and external characteristic parameters, the influence of stator blade outlet angle on the performance is revealed. The research results can provide some technical guidance for the blade design and performance optimization of torque converter.

Key words: torque converter, computational fluid dynamics, blade outlet angle, three-dimensional vortex, velocity field

CLC Number:

TH137

CHAI Bosen, CONG Hao, YANG Haomin, PAN Jun, ZHU Guoren. Analysis of Influence of Stator Blade Outlet Angle on Performance of Torque Converter[J]. Journal of Mechanical Engineering, 2024, 60(11): 105-114.

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