考虑粗糙渗流效应的指尖密封总泄漏性能分析  

Analysis of Total Leakage Performance of Finger Seal Considering theRough Seepage Effect

作　　者：赵海林 陈国定[1] 苏华[1] ZHAO Hailin;CHEN Guoding;SU Hua(School of Mechanical Engineering,Northwestern Polytechnical University,Xi’an 710072)

机构地区：[1]西北工业大学机电学院,西安710072

出　　处：《机械工程学报》2020年第3期152-161,共10页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(51575445)。

摘　　要：指尖密封作为近年来一种新型密封技术,其泄漏性能一直是密封领域的研究热点。将流体通过指尖片表面粗糙接触界面微观空隙的泄漏视为指尖密封的侧隙泄漏,基于压力流量因子和哈根-泊肃叶定律构建了指尖密封侧隙多孔介质结构渗透率的计算方法,进而建立了基于多孔介质结构的指尖密封侧隙泄漏性能分析数值模型;然后计入指尖密封侧隙泄漏的影响,构建了考虑指尖密封侧隙泄漏和主流道泄漏的指尖密封总泄漏分析方法;最后在此基础上分析了指尖片表面形貌参数、指尖密封工况参数对指尖密封侧隙泄漏、主流道泄漏和总泄漏的影响,研究了指尖密封侧隙泄漏和主泄漏的权重比例。结果表明:指尖密封侧隙泄漏随着指尖片表面均方根粗糙度、指尖密封上下游压差的增加而增加;当指尖片表面纹理从横向纹理向纵向纹理变化时,指尖密封侧隙泄漏亦逐渐增加;当指尖片表面均方根粗糙度较大时,指尖密封侧隙泄漏在指尖密封总泄漏中占主要地位,当转子径向位移激励较大时,指尖密封主流道泄漏占主要地位。该研究有助于完善指尖密封泄漏分析理论体系,具有较高的学术价值和工程意义。As a new sealing technology,the leakage performance has been one of the hot topics in sealing field.The leakage through the micro voids at the contact interface between rough surfaces of finger element is regarded as the finger seal side leakage,a method of calculating the permeability of porous medium is proposed based on the pressure flow factor and Hagen-Poiseuille law,and the numerical model for calculating the side leakage based on the porous medium theory is established.Then taking into account the finger seal side leakage,the analysis method for total leakage of finger seal is developed.Finally,the influence of the surface topography parameters and the operating conditions on the side leakage,the main leakage and the total leakage is analyzed.In addition,the proportions of the side leakage and main leakage are also studied.The results show that the finger seal side leakage increases with the increase of the RMS roughness and the pressure difference between upstream and downstream finger seal,and when the finger element surface roughness texture direction changes from transverse to longitudinal,the finger seal side leakage also increases.On the other hand,the side leakage becomes dominant as the surface of finger element is rough enough,but the main leakage dominates when the radial displacement excitation of the rotor is larger.This research contributes to the improvement of the theoretical system of the finger seal leakage analysis.

关 键 词：指尖密封 多孔介质 粗糙度 纹理 压力流量因子 

分 类 号：TB42[一般工业技术]