中文摘要：

为提升液力变矩器性能，需要进一步研究液力变矩器内部流动，获取流动特征规律。针对某型液力变矩器进行不同速比下内部流场的CFD数值模拟，并分析其流动现象，得出该变矩器内流场中流动状态的速度、漩涡的分布规律。结果表明，流体的相对速度随速比升高有下降趋势，漩涡结构随速比增大而增大。相同速比下，不同叶轮中、不同弦面的流体出现不同类型二次流。通过CFD研究发现二次流主要出现在泵轮和导轮中，其中叶轮进出口处漩涡湍动能较高，能量损失较大。流场分布规律研究可以指导液力变矩器设计，使流场分布合理并且减少二次流等现象，对提高液力变矩器的效率有重要意义。

英文摘要：

In order to enhance the performance of torque converters, we need to do further research on the internal flow of torque converters and get the flow characteristics. In this paper, the flow field of a certain torque converter is computed under different speed ratios by the CFD numerical simulation. We analyze the flow phenomena and fig- ure out the flow velocity, and the distribution of the vortex. The results show that the relative velocity of the fluid lower as the speed ratio increases, and the distribution of the secondary flow is also different. For the same speed ratio, the velocity distribution and the turbulent kinetic energy of the vortex are quite different at different impel- lers, chord planes or wing surfaces. From the results of the CFD numerical simulation, we find that the secondary flow mainly occurs in pump and stator. In addition, the turbulent kinetic energy is higher near impeller outlet, consequently means larger energy loss. We can use the distribution of the flow field to guide the inlet and design of torque converters, and make the flow field distribution more reasonable and improve the efficiency of the torque converter, which is very meaningful.