Flow Field Analysis Of Torque Converter And Blade Structure Optimization

The hydraulic torque converter, which uses liquids as working medium, is the soft connecting component between engine and transmission. As an important component of motor vehicle transmission system, it can transmit torque, change speed and torque, and realize clutch. Currently there is still some distance between the domestic development of hydraulic torque converter and that abroad. Thus, it is the concern in the industry how to combine 3D software feature modeling and parametric technique to develop a fast, high-efficiency hydraulic torque converter design module.In this thesis, the author organized the work in three aspects to study hydraulic torque converter: modeling, simulation and optimization. Based on a mathematical model, taking advantage of the secondary development of UG NX, and using GRIP language, API function and C language, the author developed a hydraulic torque converter design module. Using a certain hydraulic torque converter as prototype, ANSYS FLUEN T software was employed to make simulation and analysis of the fluid field. The performance curve, speed distribution and pressure distribution under different working conditions were obtained. Then, optimization was made for five geometric parameters: pump blade thickness, turbine blade thickness, stator blade thickness, turbine inlet deflection angle and turbine outlet deflection angle. Using orthogonal test, the above parameters were optimized to 2mm, 4mm, 3mm, 42° and 107° respectively, where the power efficiency was increased from 84.3% to 85.4%. Also, to obtain the highest power efficiency under a certain range of stall torque ratio and pump capacity factor, the response surface was used to optimize the blade parameters. 1mm for pump blade thickness, 1mm for turbine blade thickness, 4 mm for stator blade thickness, 49° for turbine inlet deflection angle and 107° for turbine outlet deflection angle were obtained, where the power efficiency was increased to 8 6.3%. The results showed that the higher power efficiency can be obtained by using response surface method than that by using orthogonal test. The optimization result using response surface method provided reference for improving the performance of hydraulic torque converter. The research method can also be a reference for developing hydraulic torque converter.