电机液膜密封的结构设计及性能分析

Structure Design and Performance Analysis of Motor Liquid Film Seal

为解决电机密封在高转速、双向旋转工况下润滑介质向电机绕组内侧泄漏的问题,设计一套液膜密封装置。采用有限差分法离散柱坐标系下雷诺方程,利用SOR求解端面液膜压力分布,比较枞树槽和T型槽的液膜密封装置的泵送性能、承载能力及泄漏量分别随转速、膜厚的变化规律。结果表明:同条件下枞树槽压力峰值大于T型槽;枞树槽在较低的转速或较大的膜厚下即可实现泄漏介质的完全反输;同膜厚下枞树槽开启力大于T型槽且枞树槽开启力随转速、膜厚变化明显;综合分析,枞树槽较适用于高转速、双向旋转的电机液膜密封。

A liquid film seal device was designed to solve the problem contributed by motor＇ s lubricating medium leak- age to motor winding at special conditions such as high speed rotation and positive and negative rotation.The finite differ- ence method was used to discrete the Reynolds equation in the cylindrical coordinate system and the film pressure distribu- tion of end face was obtained by using SOR solver.The variation of pumping performance, bearing capacity and leakage with the rotation speed and film thickness were compared for the liquid film seals with fir tree groove and T groove. Results show that the pressure peak value of fir tree groove seal is larger than that of T groove seal under the same conditions.Fir tree groove seal can realize the anti-pumping of leakage medium completely in lower speed or larger film thickness.The opening force of fir tree groove seal is larger than that of T groove seal under the same film thickness, and the opening force of fir tree groove seal changes obviously with the rotation speed and film thickness. It should be given priority to fir tree groove on the motor liquid film seal in comprehensive analysis .