阀控充液式液力偶合器瞬态充液流场及转矩特性预测

阀控充液式液力偶合器常被安装布置于刮板输送机的电机与减速器之间，利用其充液调速特性，实现刮板输送机的软启动。为了预测阀控充液式液力偶合器瞬态充液过程的流场及转矩特性，以循环圆直径为500 mm的偶合器为分析模型，应用仿真软件CFX(Computational Fluid Dynamics X),采用非均一化两相流模型与SST(Shear Stress Transport)湍流模型，对充液过程的瞬态特性进行了数值模拟研究，获取了不同工况下的压力场、速度场及转矩值，根据压力、速度分布及变化规律分析了不同工况下泵轮转矩变化趋势，并得到了不同充液率下泵轮转矩系数的拟合公式。结果表明，整体上转矩随着充液率的增大而呈抛物线形式递增，随着速比的增大而减小，并由于环流状态的改变，出现转矩下降速率跌落现象。分析结果预测了阀控充液式液力偶合器的流场及转矩特性，为液力偶合器的使用与设计提供了合理的参考。

Transient Fluid-filled Flow Field and Torque Characteristic Prediction of Value-controlled Fluid-filled Hydraulic Coupling

The valve-controlled liquid-filled hydraulic coupling is often installed between the motor and the reducer. By using its liquid-filled speed regulation characteristics, the soft start of the scraper conveyor is realized. In order to predict the flow field and torque characteristics of the valve-controlled liquid-filled hydraulic coupling during the transient liquid-filling process, the coupling with a circular diameter of D=500 mm was used as the analytical model and inhomogeneous model and SST turbulence model were adopted. The simulation software CFX was applied to simulating transient characteristics of the liquid filling process. The pressure field, velocity field and torque value under different working conditions were obtained, and the changing trend of the torque of pump wheel was analyzed. And the fitting formulas of the torque coefficient under different filling rates were obtained. The results show that the overall torque increases in a parabolic form with the increase of filling rate, and decreases with the increase of speed ratio. Due to the change of the circulation state, the torque drop rate drops. The analysis results predict the flow field and torque characteristics of the valve-controlled liquid-filled hydraulic coupling, which provides a reasonable reference for use and design of the hydraulic coupling.