Analysis Of The Effect Of Blade Parameters On The Performance Of Hydraulic Torque Converter Based On CFD

Hydraulic torque converter is one of the most important components of hydraulic transmission,which has been widely used in the automatic transmission.In the design process of the torque converter,the most core part is the cascade system,which impact on the performance of hydraulic torque converter directly.Cascade system parameters include leaf inlet angle,exit angle,leaf number and cycle circle and so on.In this paper,a model torque converter is used as the research object,and CFD is used as the carrier to study the influence of the number of blades and the inlet and outlet angles on the performance of the torque converter.Firstly,the working characteristics of the three working wheels of the torque converter are analyzed.The mathematical model of the torque converter is established according to the energy balance,and its static characteristics are also analyzed.With the aid of the three coordinates laser scanner,the whole point cloud data of the working wheel of the torque converter are obtained.The three-dimensional solid model of hydraulic torque converter is obtained by Imageware post-processing and UG software.The simplified flow path model is introduced into ICEM for meshing,and the three-dimensional flow field is simulated by FLUENT of CFD software.The numerical simulation of the three-dimensional flow field of the hydraulic torque converter with different working wheels(pump wheel,turbine and guide wheel)is carried out under the condition of high speed ratio.The velocity and pressure regular of import and export of the wheel is obtained and analyzed.At the same time,according to the calculation results of three dimensional flow field,the influence of blade number of different working wheels on the torque converter characteristics is analyzed.Four typical schemes are selected according to the combination of the number of working blades.Compared the calculation results and experiment results,the accuracy of the calculation results of the three-dimensional flow field is verified.The performance of torque converter with different blade number is compared and analyzed,and the influence of different blade number combinations on torque converter performance is obtained.According to the mathematical model of hydraulic torque converter,the influence of blade angle on performance parameters of torque converter is studied at different speed ratio.Through the numerical simulation of three-dimensional flow field at high speed,the difference of velocity and pressure distribution between the inlet and outlet of each working wheel at different inlet and outlet angles is obtained,and the reasons are clarified.Because the great impact of the guide wheel and pump wheel outlet angle on the performance of torque converter,the characteristics of the pump wheel and guide wheel with different outlet angles of the torque converter are contrasted and analyzed through the three-dimensional flow field calculation results.,which obtain the influence of the outlet angle of the torque converter.