Research On The Main Flow Features And Stator Blade Of Flatness Torque Converter

Hydraulic torque converter is a kind of complex turbomachinery, as power transmission parts, it has many advantages such as external load adaptability, higher output torque in low speed and torsional vibration and shock absorption.But since the1990 s, torque converter axial size has became smaller, so does the circle width.The resulting is the circle flat, causing to the shock loss increased in stator and hydraulic performance is deteriorating, and transfer efficiency is further reduced. Therefore, the important role stator plays in the torque converter, the research on the characteristics of flow field and the stator blade in the flat hydrodynamic torque converter is of great significance.This paper is on the basis of the theory of fluid dynamics and the characteristics of single channel and the whole flow model, the torque converter steady and unnon steady calculation method were respectively studied. In addition, the numerical simulation results are compared with the external characteristic rig test to verify the accuracy of the numerical solution.By means of the numerical simulation method above, the two important internal flow field characteristics which effect performance of the hydraulic torque converter are studied. Firstly, according to the characteristics of flat torque converter, the mechanism of fluid loss in the inner fluid field is studied. It is found that the secondary flow in the inner flow field is the main reason for the low transmission efficiency of the torque converter. Then, by the RNG k-? turbulence model and sliding mesh technique, the unsteady pressure fluctuation intensity of the hydraulic torque converter is analysised.Finally, the effect of different ratio of internal pressure fluctuation is studied, provideing a theoretical basis for the three-dimensional unsteady turbulent flow, vibration response and fatigue failure of impellers.For the adverse effects of the flat characteristics in stator internal flow, on the basis of the theory of hydrodynamic transmission and W240B-SH type hydraulic torque converter as the prototype, with the help of orthogonal experiment design and numerical simulation method, under the different stator blade parameters, including inlet and outlet angle, the leaf rolling angle, blade thickness and arc control coefficient, the characteristics of torque converter and the stator inner flow field changes is analysis in detail.In order to further optimize the stator blade with avoiding the lack of existing optimization methods. In this paper, the statistical analysis of the use of the torque converter is carried out under the typical cycle driving conditions. Meanwhile the stalltorque ratio as the optimization objective, highest efficiency as the constraint conditions of the optimization model is put forward. Finally, the optimization result shows that the highest efficiency in the basis of above 84%, the optimization of stall torque ratio increased by 10.83%, which providing a reference for the future of the torque converter parameters analysis and optimization.