Calculation Errors of Performance Parameters of Hydraulic Torque Converter and Their Corrections

In order to improve the numerical simulation precision of hydraulic torque converters, the performance parameters, including torque ratio, efficiency and pump capacity factor, were calculated by the CFD (computational fluid dynamics) method. Calculation errors of the performance parameters were analyzed, and the corresponding correction methods were proposed. Through analyzing the impact of compensating fluid flow on the calculation error of pump capacity factor, its correction method was proposed. The results show that the neglect of friction loss and compensative flow in numerical simulations will result in calculation errors of the performance parameters of a hydraulic torque converter. The error correction method for friction loss can decrease the maximal relative errors of torque ratio and efficiency from 16.2% to 13.9%, and the error correction method for pump capacity factor can decrease its maximal relative error from 13.9% to 7.3%.