液氢涡轮泵孔型阻尼密封设计与性能评估  

Investigations on the scheme design and performance evaluation of the hole-pattern damper seal in a liquid hydrogen turbopump

作　　者：李志刚[1] 安阳[2] 叶小强[2] LI Zhigang;AN Yang;YE Xiaoqiang(Institute of Turbomachinery, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China;Beijing Aerospace Propulsion Institute, Beijing 100076, China)

机构地区：[1]西安交通大学能源与动力工程学院叶轮机械研究所,陕西西安710049 [2]北京航天动力研究所,北京100076

出　　处：《火箭推进》2022年第2期105-116,共12页Journal of Rocket Propulsion

基　　金：国家自然科学基金面上项目(51776152)。

摘　　要：针对某液氢涡轮泵级间迷宫密封流体激振诱发转子涡动失稳问题,开展了孔型阻尼密封方案设计及密封泄漏特性和转子动力特性评估研究。通过不同密封间隙、孔径和孔深等关键几何参数的组合,共设计液氢孔型阻尼密封方案25种。采用定常CFD(computational fluid dynamics)数值预测方法,计算分析了密封间隙、孔径和孔深对液氢孔型阻尼密封泄漏量的影响规律;采用基于多频单向转子涡动模型、动网格技术和转子动力特性系数频域识别方法的非定常CFD摄动数值预测方法,计算分析了孔径和孔深对液氢孔型阻尼密封转子动力特性系数的影响规律。研究表明:液氢孔型阻尼密封的孔深和孔径的比值(密封孔深径比H/D)存在一个临界值(H/D=0.5附近),此时密封泄漏量最小;H/D<0.5时,液氢孔型阻尼密封泄漏量对孔深变化不敏感(小于4.5%);较大孔径的液氢孔型阻尼密封具有更小的有效刚度;较小孔深的液氢孔型阻尼密封具有更小的有效刚度和更大的有效阻尼;综合考虑液氢孔型阻尼密封泄漏特性和转子动力特性,液氢孔型阻尼密封应选取较小间隙、较大孔径和最佳深径比以内(H/D<0.5)的较小孔深。To solve the rotor vibration instability induced by the fluid-response forces of the inter-stage labyrinth seal in a liquid hydrogen turbopump, investigations on the scheme design of the hole-pattern seal were carried, as well as the performance evaluation of the seal leakage and rotordynamic characteristics.Total 25 seal schemes were designed for the liquid hydrogen hole-pattern seal, by the combination of various sealing clearances, hole diameters and hole depths.The effects of sealing clearance, hole diameter and hole depth on the seal leakage characteristics were calculated and discussed for the liquid hydrogen hole-pattern seal, using a steady CFD(computational fluid dynamics)numerical method.The effects of hole diameter and hole depth on the seal rotordynamic characteristics also were predicted and analyzed for the liquid hydrogen hole-pattern seal, using a transient CFD perturbation numerical method based on the multi-frequency one-dimensional rotor whirling model, the mesh deformation technique and the identification method of the rotordynamic force coefficients in frequency domain.Results show that there is a critical value for the ratio of hole depth to the hole diameter(H/D approaches to 0.5) where the liquid hydrogen hole-pattern seal possesses the least leakage flow rate.The hole depth has a very weak influence(less than 4.5%) on the leakage flow rate of the liquid hydrogen hole-pattern seal when H/D<0.5.The liquid hydrogen hole-pattern seal with the larger hole diameter generates the smaller effective stiffness.The liquid hydrogen hole-pattern seal with the shallower hole depth generates the smaller effective stiffness and the larger effective damping.Comprehensively considering the seal leakage and rotordynamic characteristics, for the liquid hydrogen hole-pattern seal, it is better to choose the smaller sealing clearance, the larger hole diameter and the shallower hole depth with H/D<0.5.

关 键 词：液氢涡轮泵 孔型阻尼密封 转子多频涡动模型 非定常摄动数值方法 泄漏特性 转子动力特性 

分 类 号：V434.21[航空宇航科学与技术—航空宇航推进理论与工程]