Abstract:

The engine nozzle seal operates under extreme conditions characterized by high temperature, high pressure and vibration working conditions. Improper design may result in seal failure, which influences the operating performance and safety of the entire engine. In order to study the sealing performance of nozzle seal, a finite element model of nozzle seal structure was established. The effects of medium pressure, axial float and radial polarization on the sealing performance of nozzle were analyzed. The leakage rate of nozzle seal under dynamic and static conditions was tested. The results showed that the contact area of the main seal C-O ring presented a five-stage ladder distribution, and the structure had good self-tightening and stable fit, which could ensure reliable operation under high pressure medium. Under the conditions of axial float and radial polarization, the main seal C-O ring still had good dynamic follow-up performance, and the radial polarization was more likely to cause leakage than the axialfloat, which provided the suggest for the design and use of the nozzle seal. The leakage rate of the nozzle seal was less than 1mL/s under various high parameter working conditions, which showed good sealing performance of the nozzle seal.

Key words: numerical simulation, experimental validation, sealing performance, vibration, nozzle seal

摘要：

发动机喷管密封处于高温、高压及振动等高参数工况环境下，如设计不当可能导致密封失效，进而影响整个发动机的运行性能和安全性。为研究喷管密封的密封性能，建立喷管密封结构有限元模型，本文分析了介质压力、轴向窜动及径向偏振工况对喷管密封性能的影响，试验测试了喷管密封在动静态工况下的泄漏率。结果表明，主密封C-O形圈的接触区呈现五级阶梯式分布，且结构具有良好的自紧性和稳定的贴合性，可保证其在高压介质下可靠工作；在轴向窜动与径向偏振工况下，主密封C-O形圈仍具有良好的动态追随性能，且径向偏振比轴向窜动更容易造成泄漏，为喷管密封的设计和使用提供了基础；喷管密封在各个高参数工况下泄漏率均小于1mL/s，展现出了良好的密封性能。

关键词: 数值模拟, 实验验证, 密封性能, 振动, 喷管密封