非圆行星齿轮水压马达轴向间隙对容积效率的影响

Effect of Axial Clearance on Volumetric Efficiency of Non-circular Planetary Gear Hydraulic Motors

将液压马达中的液压油换成自然水会导致轮系的泄漏量增大,马达容积效率降低。为了提高非圆行星齿轮水压马达的容积效率,定量分析了轮系与配流盘的轴向间隙对马达容积效率的影响。首先,根据旋转平面缝隙泄漏原理和流体内摩擦力推导出轮盘之间的泄漏和功率损失计算式,从而计算出在30 MPa压差下马达轴向间隙的最优解;然后,在考虑制造误差的基础上,基于动网格和用户自定义函数(User-Defined Function,UDF)编程技术,检测分析马达在不同轴向间隙下的泄漏量以及容积效率,同时计算出同等条件下马达的理论容积效率;最后,将两者加以对比,得出不同工况下马达容积效率的变化趋势与极小值。研究表明,从选取轴向间隙值的计算结果来看,当轮盘的平面度为0.01 mm时,在工作压差30 MPa以内,马达的容积效率不低于77.28%。研究为后续马达的结构改进提供了依据。

Replacing the hydraulic oil in hydraulic motors with the natural water will lead to an increase in the leakage of the wheel train and a decrease in the volumetric efficiency of motors.In order to improve the volumetric efficiency of the non-circular planetary gear hydraulic motors,the influence of axial clearance between the wheel train and the distribution plate on the volumetric efficiency of the motor is quantitatively analyzed.Firstly,according to the principle of the gap leakage in the rotating plane and the friction force in the fluid,the leakage and power loss formula between the wheels were derived,so as to calculate the optimal solution of the axial clearance of the motor under 30 MPa pressure difference.Secondly,on the basis of considering the manufacturing error,based on the dynamic grid and user-defined function(UDF)programming technology,the leakage amount and volumetric efficiency of the motor under different axial clearances were detected and analyzed,and the theoretical volumetric efficiency of the motor under the same conditions was calculated.The two were compared to obtain the change trend and the minimum value of motor volumetric efficiency under different working conditions.The results show that from the calculation results of selecting the axial clearance value,when the flatness of the wheel is 0.01 mm,the volumetric efficiency of the motor is not less than 77.28%within the working pressure difference of 30 MPa.It provides a basis for the structural improvement of subsequent motors.