型槽参数对斜直线槽液膜密封性能的影响

为进一步探索斜直线型槽对密封性能的影响机制，基于质量守恒边界并定义液膜密度比，建立斜直线槽液膜密封动压润滑模型；采用有限差分离散方程，对比分析液膜空化理论与实验值，验证计算模型与程序准确性；研究斜直线型槽参数包括槽数、槽深、径向和周向槽宽比对密封性能的影响。结果表明：不同倾斜角时，在临界范围内，增加槽数或增大槽深均有助于提升液膜承载力、增大泄漏量并有效降低液膜空化，尤其在较大倾斜角下；在一定范围内，虽均增大径向和周向槽宽比可提升液膜承载力、促进液膜空化发生及增大泄漏量，但影响规律不尽相同。以提升液膜承载力为目标，得出的最优型槽参数为槽数42、槽深25μm、径向和周向槽宽比分别为0.7和0.6。

Effects of Groove Parameters on Sealing Performances of Liquid-film Seal with Inclined-straight Grooves

To further explore the effect mechanism of the inclined-straight groove on the sealing performances,the hydrodynamic lubrication model of the liquid-film seal with inclined-straight groove was established based on the boundary of mass conservation and the liquid film density ratio defined.The finite difference method was adopted to discretize the equation,and the theoretical and experimental values of cavitation zone in the liquid film were compared and analyzed to verify the accuracy of the calculated model and program.The influences of structure parameters of inclined-straight groove on the sealing performances were investigated，including groove number,groove depth,radial and circumferential groove width ratios.Results show that within the critical range under different slant angles,increasing the groove number or groove depth is helpful to improve the liquid-film load-carrying capacity,increase the leakage and effectively reduce the liquid-film cavitation zone,especially under the condition of larger slant angles.In a certain range,although increasing the radial and circumferential groove width ratios can enhance the liquid-film load-carrying capacity,promote the cavitation occurrence,and increase leakage,the influence laws are not the same.With the liquid-film load-carrying capacity as the improvement goal,the optimal groove parameters are as follows:groove number 42,groove depth 25 μm,radial and circumferential groove width ratio 0.7 and 0.6,respectively.