表面粗糙度对螺旋槽干式气体密封性能的影响

Effect of Surface Roughness on Performance of a Spiral Groove Gas Seal

考虑螺旋槽干式气体端面密封(S-DGS)的表面粗糙度,通过求解可压缩流平均雷诺方程,研究了不同速度条件下密封端面不同区域的各向同性表面粗糙度对密封气膜刚度和泄漏量的影响。结果表明:密封端面各区域表面粗糙度对密封性能的影响规律各不相同,并且转速对表面粗糙度与密封性能的关系产生影响;为满足气体密封具有较高气膜刚度的同时具有较低的泄漏量,同时满足较高的性价比,设计时应选取合适的表面粗糙度值。

The average Reynolds equation was established and solved for compressible viscous gas to get the hydrodynamic pressure distribution in the interface between the two faces with isotropic surface roughness of a spiral groove gas face seal （S-DGS）. The effects of surface roughness at different areas of the seal faces on the performances such as gas film stiffness and leakage rate of a S-DGS were studied. The results show that the surface roughness at different areas of the mating faces behaves differently, and the relationship between surface roughness and the sealing performance is affected by the shaft rotating speed. To get higher gas film stiffness while maintaining lower leakage rate and get the higher ratio of sealing performance to seal price, it is important to design a S-DGS surfaces with suitable value of roughness.