蜂窝密封流动特性的数值研究和泄漏量计算公式的构造  

Numerical Investigation on Discharge Behavior and Predication Formula Establishment of Leakage Flow Rate of Honeycomb Seal

作　　者：李志刚[1] 李军[1] 丰镇平[1] 

机构地区：[1]西安交通大学叶轮机械研究所,西安710049

出　　处：《机械工程学报》2011年第2期142-148,共7页Journal of Mechanical Engineering

基　　金：国家重点基础研究发展计划(973计划;2007CB707705);国家自然科学基金(50506023)资助项目

摘　　要：采用标准k-ε紊流模型和三维Reynolds-Averaged Navier-Stokes方程求解方法,利用商用CFD软件ANSYS CFX数值研究压比、蜂窝芯格直径、深度对蜂窝密封泄漏特性的影响。分析蜂窝密封在6种压比、3种蜂窝芯格直径、3种蜂窝芯格深度、恒定密封间隙和转速下的泄漏特性,研究结果表明:蜂窝密封泄漏量随压比的增加而增大;相同转速、压比和密封间隙下,合适的蜂窝芯格深度与直径能提高蜂窝密封的封严性能;蜂窝芯格深度一定时,蜂窝密封的泄漏量随芯格直径的减小而增大;芯格直径一定时,随蜂窝芯格深度的增大,蜂窝密封泄漏量先减小后增大。在经典迷宫密封泄漏量Egli计算公式的基础上,通过引入有效密封齿数和蜂窝芯格结构系数,构造能够可靠预测蜂窝密封泄漏量的计算公式并进行数值验证。The effects of honeycomb cell on the discharge behavior of honeycomb seal and referenced labyrinth seal are numerically investigated based on the Reynolds-Averaged Navier-Stokes（RANS） equations and standard turbulent model using commercial CFD software ANSYS CFX.The leakage flow characteristics of the honeycomb seal at three cell sizes,three cell depths,six pressure ratios,constant sealing gap and rotational speed flow condition are analyzed.Numerical simulation results show that the leakage of labyrinth seal and that of honeycomb seal both increase with an increase in pressure ratio.The honeycomb seal with appropriate cell diameter and depth can improve its sealing performance at the same rotational speed,pressure ratio and sealing clearance.The leakage flow rate of honeycomb seal increase with increasing cell diameter at the fixed cell depth.At the same cell diameter,the leakage flow rate of honeycomb seal decreases firstly and then increases with the increase of cell depth.An improved prediction formula of leakage flow rate of honeycomb seal is presented on the basis of classical Egli equation of labyrinth seal through introducing effective seal fins coefficient and honeycomb cell structural coefficient.The reliability and accuracy of the presented prediction equation for honeycomb seal is demonstrated by the CFD computational results.

关 键 词：蜂窝密封 泄漏特性 计算公式 数值模拟 

分 类 号：TH136[机械工程—机械制造及自动化]