刷式密封刷丝浮升效应流固耦合数值研究  

Numerical investigation on bristles buoyancy effect of brush seals with fluid-structure interaction

作　　者：孙基生 孙丹 赵欢 慕伟 张杰一 温帅方 SUN Jisheng;SUN Dan;ZHAO Huan;MU Wei;ZHANG Jieyi;WEN Shuaifang(Liaoning Key Laboratory of Advanced Measurement and Test Technology for Aviation Propulsion System,School of Aero-engine,Shenyang Aerospace University,Shenyang 110136,China;Shenyang Engine Research Institute,Aero Engine Corporation of China,Shenyang 110015,China;Key Laboratory for Power Transmission,Aero Engine Corporation of China,Shenyang 110115,China)

机构地区：[1]沈阳航空航天大学航空发动机学院、辽宁省航空宇航推进系统先进测试技术重点实验室,沈阳110136 [2]中国航发沈阳发动机研究所,沈阳110015 [3]中国航发动力传输航空科技重点实验室,沈阳110015

出　　处：《航空动力学报》2024年第9期95-105,共11页Journal of Aerospace Power

基　　金：国家自然科学基金(52075346);先进航空动力创新工作站(依托中国航空发动机研究院设立)项目(HKC2020-02-030);辽宁省教育厅基础研究项目(JYT2020047)。

摘　　要：基于简化悬臂梁模型分析了刷式密封刷丝浮升效应理论,采用ALE(arbitrary Lagrange-Euler)流固耦合方法建立了刷式密封刷丝浮升效应三维瞬态数值求解模型,在验证了数值模型准确性基础上,研究了刷丝总体变形特性,量化分析了刷丝自由端轴向、径向和总体变形量,研究了结构参数与工况参数对刷式密封刷丝浮升效应的影响规律,揭示了刷式密封刷丝浮升效应诱发机理。研究结果表明:刷式密封刷丝浮升效应是前排刷丝受非定常径向气流作用产生的刷丝扰动现象,刷丝浮升效应会使前排刷丝向来流方向发生较大变形,并使前排刷丝与转子面产生径向间隙,泄漏量增加。当进出口压比从2提高至4,刷丝自由端平均变形量增加了47%,将前挡板保护高度从1.5 mm提高至2.5 mm,刷丝自由端平均变形量增加了36%,均使刷丝浮升效应增强。刷式密封前挡板与刷丝束间隙提供的径向气流通道,进出口压差在前挡板与刷丝束间隙内产生的径向压力梯度是刷丝浮升效应的诱发条件,提高刷丝直径和降低前挡板与刷丝束间隙均可降低刷丝浮升效应。The bristles buoyancy effect of brush seal directly affect its sealing performance and service life.The theory of brush seal bristles buoyancy effect was analyzed,and the three-dimensional transient numerical model of brush seal bristles buoyancy effect was established using arbitrary Lagrange Euler(ALE)fluid-structure coupling method.Based on the accuracy of numerical model,the overall deformation characteristics of bristles were studied,and the axial,radial and total deformations of bristle tips were quantitatively analyzed.The effects of structural parameters and working parameters on bristles buoyancy effect of brush seal were studied,and the inducing mechanism of bristles buoyancy effect of brush seal was revealed.The research results showed that the bristles buoyancy effect of brush seal contributed to the disturbance of the front bristles caused by the unsteady radial airflow.The bristles buoyancy effect of brush seal can cause large deformation of the front bristles in the direction of the flow,generate radial clearance between the front plate and the rotor surface,and increase the leakage.When the inlet and outlet pressure ratio increased from 2 to 4,the average deformation of bristle tips increased by 47%,and the protection height of the front plate increased from 1.5 mm to 2.5 mm,and the average deformation of bristle tips increased by 36%,both of which enhanced the bristles buoyancy effect.The radial airflow channel was provided by the clearance between the front plate and the bristle pack,and the radial pressure gradient was generated by the inlet and outlet pressure difference in the clearance between the front plate and the bristle pack as the inducing condition of the bristles buoyancy effect.The bristles buoyancy effect can be reduced by increasing the diameter of the bristles and reducing the clearance between the front plate and the bristle pack.

关 键 词：刷式密封 刷丝浮升效应 ALE(arbitrary Lagrange-Euler)方法 流固耦合 变形特性 

分 类 号：V233.5[航空宇航科学与技术—航空宇航推进理论与工程]