Abstract

The impact of the viscosity and the density of transmission fluids on the performance of a hydraulic torque converter was examined. Four different transmission fluids were evaluated under different operating conditions by fluid temperature and speed ratio. The study utilized the computational fluid dynamics (CFD) method, which modeled the transmission fluid as an incompressible and Newtonian fluid and simulated the flow field inside the torque converter by numerically solving the governing equations of the fluid flow. The simulated flow fields of four different fluids were examined via mechanical performance parameters of the torque converter, including the k-factor and the efficiency. The transmission fluids were also experimentally evaluated using the modeled torque converter at two independent laboratories. Comparisons of the model predictions with the experimental results showed that the computational data agree well with the test data. A parametric study was performed by using the validated CFD model. The results indicate that the viscosity and density of the fluid have opposing effects on the performance of the torque converter studied.

摘要

检查了传动液的粘度和密度对液力变矩器性能的影响。在不同的操作条件下，通过流体温度和速度比对四种不同的传动液进行了评估。该研究利用计算流体动力学 (CFD) 方法，将变速器流体建模为不可压缩的牛顿流体，并通过对流体流动的控制方程进行数值求解来模拟变矩器内部的流场。通过变矩器的机械性能参数检查四种不同流体的模拟流场，包括k-因素和效率。还在两个独立实验室使用建模的变矩器对传动液进行了实验评估。模型预测与实验结果的比较表明，计算数据与测试数据吻合良好。使用经过验证的 CFD 模型进行了参数研究。结果表明，流体的粘度和密度对所研究的变矩器的性能具有相反的影响。