液氧涡轮泵阻尼密封设计与动力学特性研究  

Investigation on the Structural Design and Rotordynamic Characteristicsfor theDamper Seal in a Liquid Oxygen Turbopump

作　　者：靳志鸿 胡锦华 李志刚[1] 李军[1] JIN Zhihong;HU Jinhua;LI Zhigang;LI Jun(School of Energy and Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China;Xi’an Aerospace Power Research Institute,Xi’an 710100,China)

机构地区：[1]西安交通大学能源与动力工程学院,西安710049 [2]西安航天动力研究所,西安710100

出　　处：《西安交通大学学报》2023年第9期43-53,61,共12页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(52176042)。

摘　　要：为评估进口高预旋对动密封性能的影响,提出了能够同时模拟动密封进口压力场和速度场的“虚拟旁路边界”计算模型和动密封非定常流体激振数值预测方法。针对某型液氧涡轮泵离心叶轮前凸肩动密封,开展了迷宫、蜂窝和孔型阻尼密封方案设计、性能比较和深度变推力发动机涡轮泵密封动力学适应性研究,比较了液氧涡轮泵额定工况下3种动密封方案性能,计算分析了6种发动机推力负荷(10%~100%)、高进口预旋(预旋比为0.77)下孔型阻尼密封的泄漏量和转子动力特性系数。结果表明:在额定工况下,相比于迷宫密封,蜂窝和孔型阻尼密封具有更优的封严性能(泄漏流量分别减小了17.9%和17.5%)和动力学性能(同步频率下有效阻尼分别增大了180%和87%,穿越频率从661 Hz分别减小到了287 Hz和275 Hz);在发动机深度变推力工况下,孔型阻尼密封具有较大的同步频率有效阻尼;受高进口预旋的影响,有效阻尼的穿越频率随推力负荷的增大而显著增大(从50 Hz增大到430 Hz),减小了密封提供正阻尼的抑振频率区间;在大推力工况下,可通过在密封入口设置防旋板等止旋装置减小预旋、提高转子稳定性。In order to evaluate the effect of high inlet pre-swirl on dynamic seal performance,a“virtual bypass boundary”calculation model was established to simulate the pressure field and velocity field at the inlet of dynamic seal simultaneously,and a numerical prediction method for unsteady fluid excitation of the dynamic seal was proposed.Focusing on the front shoulder seal of centrifugal impeller for a liquid oxygen turbopump,the seal design,performance comparison and rotordynamic adaptability of the labyrinth seal,honeycomb damper seal and hole-pattern damper seal were studied in this paper.The performance of three rotating seal schemes under rated operating conditions of the liquid oxygen turbopump was compared,and the leakage and rotordynamic characteristics coefficients of the hole-pattern damper seal were calculated and analyzed under six variable thrust loads(10%—100%)and high inlet pre-swirl conditions(pre-swirl ratio of 0.77).The results show that:Compared with the labyrinth seal,the honeycomb and hole-pattern damper seals possess better sealing performance(leakage rate decreases by 17.9%and 17.5%,respectively)and rotordynamic performance(effective damping increases by 180%and 87%at synchronous frequency,and the crossover frequency decreases from 661 Hz to 287 Hz and 275 Hz,respectively)under rated operating conditions;under the engine deep variable thrust conditions,the hole-pattern damper seal possesses larger effective damping at synchronous frequency;under the influence of high inlet pre-swirl,the crossover frequency of effective damping increases significantly with the increase of thrust load(from 50 Hz to 430 Hz),which reduces the vibration suppression frequency range provided by the seal with positive damping;under high thrust conditions,the rotor stability can be improved by setting anti-swirl plate and other anti-swirl devices at the seal inlet to reduce pre-swirl.

关 键 词：液氧涡轮泵 孔型阻尼密封 泄漏特性 深度变推力工况 转子稳定性 

分 类 号：TK49[动力工程及工程热物理—动力机械及工程]