摘要
采用解析法和数值计算相结合的方法,解释椭圆微孔端面机械密封的方向角所引起的几何特性改变如何影响到泄漏率.首先,得到了不同方向角下,椭圆沿速度方向上的几何收敛点的解析解.然后,基于质量守恒的JFO空化边界条件建立数值计算模型,分析了液膜的压力分布,并使用最高压力点的坐标来近似表征高压区的位置,得到了方向角与最高压力点的关系.接着,通过对比,发现几何收敛点和最大压力点位置一致,并分析了原因.最后,分析了在不同结构参数和操作参数下方向角对泄漏率的影响规律,通过分析得到,方向角的改变,使几何收敛点的位置发生改变,从而改变高低压区的分布,当高压区靠近泄漏出口时,泄漏率大;当高压区远离泄漏出口时,泄漏率小.
The orientation angle alters the geometric characteristic of ellipse, and then leads to the change of leakage rate in mechanical seal with elliptical dimples. The numerical calculation and analytical method were employed to explain this phenomenon. Firstly, the analytical solution for the geometric convergent point of ellipse in the sliding direction was worked out. Secondly, based on the mass-conservative JFO cavitation boundary condition, a numerical calculation model was developed. The coordinates of maximum pressure point represented the position of high pressure region.Thereafter, the relationship between the coordinates of maximum pressure points and orientation angles was obtained after analyzing the fluid pressure distributions. Thirdly, comparing the locations of the geometric convergent points and the maximum pressure points, two types of points were nearly overlapped, and the possible reason was discussed.Finally, the influence of orientation angle on the leakage rate was studied at various structural and operating parameters.The locations of high/low pressure regions varied because the locations of geometric convergent points changed with the orientation angles. Moreover, the leakage rate became smaller as the high pressure region moved away from the leakage outlet.
出处
《摩擦学学报》
EI
CAS
CSCD
北大核心
2017年第5期602-609,共8页
Tribology
关键词
几何收敛点
泄漏率
方向角
椭圆微孔
geometric convergent point
leakage rate
orientation angle
elliptical dimple
