球面密封结构的漏率预估

球面密封结构是国内卫星推进系统管路中经常使用的密封结构,其工作性能直接关系着卫星的在轨安全。针对球面密封的密封机理,通过非线性有限元法分析了安装条件下的密封状态。在此基础上,研究了泄漏气流的流动状态,结合Roth模型建立了分子流状态下的漏率计算模型,得出了泄漏漏率和拧紧力矩、表面粗糙度的对应关系,对检漏条件下结构的漏率进行了预估。在理论计算的同时,通过实验证明了漏率预估方法的准确性。

Leak Rate Prediction of Orbicular Seal Joint

The orbicular seal joint is widely used in the pipelines of propulsion system of satellite made in China.Its sealing reliability straightly relates with satellites' safety.At first,sealing mechanism is studied and nonlinear finite element analysis is carried out to simulate the sealing condition.Based on these results,the leak flow is studied and calculated.With the application of triangle model suggested by Roth,the molecular flow model is constructed and leak rate is predicted.In the model,the relation between leak rate and sealing condition is provided.Through the prediction,roughness and tightening torque are concluded to be the critical factors affecting the sealing capability.Meantime,a series of tests are implemented.The validity of leak rate prediction is verified by tests.