中文摘要：

为改善液力缓速器传统湍流仿真计算模型的精度，针对其流动具有强旋转、多壁面和大曲率的特点，以THB40为研究对象，基于改进的SST-Kω双方程湍流模型在CFX14．5上以不同充液率、不同转速对其进行了全流道气液两相数值模拟计算。制动扭矩计算结果显示：在95％充液率下，制动扭矩随转速升高而增大，在38％充液率下，制动扭矩随转速升高而减小。这与台架试验结果一致，两者最大误差3．6％，精度相比传统湍流模型提高了约20％，时间节省了近50％，表明该模型更加适合液力缓速器湍流流场的数值模拟计算。研究结果为深入研究液力缓速器制动机制提供了精确、高效的参考计算模型。

英文摘要：

In order to improve the raCCuraey of traditional turbulence simulation calculation models of hydraulic retarder, the improved two-equation turbulence model of SST-Kω is used to numerical simulate the turbulent flow of hydraulic retarder as the research object named THB40, under different filling ratio and different velocity with gas-liquid two-phase whole flow in the CFX14. 5, aimed at the flow characteristics of strong rotation, multi wall and large curvature. The calculation results of braking torque showed that the torque was increased as the velocity increased when the filling ratio was 95%, decreased as the velocity increased when the filling ratio was 38%. This was consistent with the results of the bench test, the maximum error between computer fluid dynamics （CFD） and bench test was 3.6%. Compared with the traditional turbulence models, the precision of improved SST-Kto turbulence model was raised about 20%, and the running time was saved by nearly 50%, which means that the turbulence model of improved SST-Kw is more suit- able for simulating turbulent flow of hydraulic retarder. The research results provide an accurate and highly efficient reference calculation model of CFD to deeply study the breaking mechanism of hydraulic retarder.