基于微尺度造型的干气密封流动有序性数值分析

Numerical Analysis of Dry Gas Seal Flow Orderliness Based on Microstructure Modeling

基于干气密封微尺度流动特性,提出一种有序微造型的干气密封模型,可在提升密封性能的同时为激光开槽提供新的借鉴和参考.选择螺旋槽和T型槽两种干气密封经典槽型为研究对象进行仿真分析,通过文献对比验证了计算方法的正确性,在有序微造型的基础上进行了有无微造型性能分析和对比,最后对微尺度下微造型的密封性能开展了系统研究.结果表明:同工况下,微造型结构的开启力较传统结构有明显提升,在高速高压及微尺度时的提升量愈加显著;T槽型的对称性使得其微造型结构兼具一定的减漏效果,且随膜厚增大减漏效果越明显;微造型深度、数量和面积对密封性能影响较大,存在一个使开启力较大同时泄漏量较小的最优槽深(螺旋槽和T型槽分别为5.5和2.5μm)及微造型深度区间(螺旋槽和T型槽皆为0.9～1.2μm).具微造型结构良好的增压性能,有助于进一步提高干气密封的稳定性.

Based on the microscale flow characteristics of dry gas seal,an ordered microstructure dry gas seal model was proposed,which provided a new reference for laser surface texture while improving sealing performance.Two kinds of classic groove -spiral groove and T groove were selected as the research object for simulation analysis.Thecorrectness of the calculation method was verified by literature comparison.Based on the optimal micro-modeling,the performance analysis and comparison of micro-modeling were carried out.The results show that,under the same working condition, the opening force of the microstructure was significantly improved compared with the traditional structure,and the lifting amount was more significant at high speed,high pressure and micro-scale.Because of the symmetry of T groove, the microstructure of T groove had a certain leakage reduction effect,and the leakage reduction effect was more obvious with the increase of film thickness.The microstructure depth,quantity and area had a great influence on the sealing performance.There existed an optimal groove depth (spiral groove and T groove were 5.5 and 2.5μm respectively)and a microstructure depth interval (both spiral groove and T groove were 0.9-1.2μm)that made the opening force larger and the leakage smaller.It had good supercharging performance of microstrueture,which was helpful to further improve the stability of dry gas seal.