热弹变形下螺旋槽干气密封泄漏量的计算与分析  

Calculation and analysis of leakage from spiral groove dry gas seal subjected to thermo-elastic deformation

作　　者：丁雪兴[1] 刘勇[1] 苏虹[1] 吴昊[1] 闫飞[1] 

机构地区：[1]兰州理工大学石油化工学院,甘肃兰州730050

出　　处：《兰州理工大学学报》2014年第6期75-79,共5页Journal of Lanzhou University of Technology

基　　金：国家自然科学基金(51165020)

摘　　要：螺旋槽干气密封在高速旋转时内部会产生一定量的热,导致密封环发生热弹变形,从而对密封性能产生影响.在速度滑移边界条件下,求出螺旋槽内的气膜压力和气膜速度,推导出气膜的能量方程,进而利用气膜的压力、速度和能量方程,通过Maple和Matlab软件求解槽内气膜的温度分布.然后由热弹变形理论,求解出密封环的变形量,获得螺旋槽内气膜厚度的解析式.利用广义雷诺方程求出理论泄漏量,并与泄漏量的实验值进行比较.研究结果表明:随着气体从外径流入内径,槽内温度的分布规律是先升高后降低,槽根部周围温度较高;热弹变形量与温度变化的规律一致,而气膜厚度的变化趋势与之相反;干气密封中的泄漏量随变形量增大而增大,有变形量的泄漏量更接近于实验值.In spiral-grooved gas seal, a finite amount of heat may be generated in high speed running, which will lead to thermo-elastic deformation of sealing ring. The thermo-elastic deformation has influence on sealing performance. The gas film pressure and velocity in the spiral groove is obtained under the boundary conditions of the slip-flow first and then the energy equation of the gas film is derived. The tem- perature distribu＇tion of the gas film in the groove is obtained by using the film pressure, film velocity, and energy equation with the help of softwares Maple and Matlab. Based on the thermo-elastic deformation theory, the deformation quality of the sealing ring and the analytic expression of gas film thickness are ob- tained. Finally, the theoretical leakage is found by using the general Reynolds equation, and compared with its experimental value. The investigation result shows that the temperature in the groove increases at first and then decreases when the gas flows from exterior into interior. The temperature next to the groove root is higher. The changing pattern of the thermo-elastic deformation is consistent with that of tempera- ture, and the variation pattern of gas film thickness is opposite from the variation pattern of thermo-elastic deformation. With the increase of deformation, the leakage will increase, and the leakage in the case of thermo-elastic deformation will be closer to the experimental value.

关 键 词：干气密封 能量方程 热弹变形 泄漏量 

分 类 号：TQ050[化学工程]