液体火箭发动机低温阀门铝垫片密封性能数值分析

In order to study the sealing performance of aluminum gasket sealing structure for cryogenic valve of a liquid rocket engine under low temperature environment, a two-dimensional axisymmetric model of the sealing structure was established by ABAQUS software. Contact pressure of aluminum gasket seal surface under low temperature working condition was calculated, and the mechanism of contact pressure drop of aluminum gasket under cyclic temperature load was studied. The results show that the contact pressure on the sealing surface decreases at low temperature due to the different linear expansion coefficient between the sealing gasket and various parts of the valve, while the complex stress-strain state on the sealing surface of aluminum gasket leads to the failure of contact pressure recovery under temperature load. The ratchet effect is produced on the sealing surface of aluminum gasket under the cyclic temperature load. The plastic strain of the gasket accumulates in the ratcheting effect, and the maximum stress decreases in the ratcheting effect. The contact force decreases gradually with the increase of temperature recycle times, and remains stable after a few period. In addition, an improved structure of sealing gasket by using conical gasket is proposed, and the effectiveness of the structure to maintain the sealing pressure under the cyclic temperature load is verified by simulation.