螺旋槽干气密封端面非平行间隙压力分布的近似解析计算

为了研究变形后螺旋槽干气密封的气膜压力分布情况,基于MUIJDERMAN的螺旋槽窄槽理论,给出了螺旋槽干气密封端面非平行间隙气膜力的1种近似解析计算方法,并结合具体算例,与平行间隙情况进行了对比.结果表明,与平行间隙情况相比,在密封面的区域内存在某一半径R处,变形前后的气膜压力保持不变.当密封端面间形成发散型(“A字形”)间隙时,在r小于R区域,气膜压力降低,而在r大于R区域,气膜压力增大.随着偏转角θ的增大,最小膜厚减小,泄漏量增大;当形成收敛型(“V字形”)间隙时,在r小于R区域,气膜压力增大,而在r大于R区域,气膜压力降低.随着偏转角θ的增大,最小膜厚和泄漏量均先减小而后增大.

An approximate analytical method of gas film pressure in non-parallel gap of spiral groove dry gas seal

To study the distribution of gas film pressure of deformed spiral groove dry gas seal, an approximate analytical method of the gas film pressure in the non-parallel gap is presented, which stems from the narrow groove theory improved by MUIJDERMAN. An example is presented, and compared with the situation of the parallel gap. The results show that there will be a radius of R, where the pressure of the gas film is the same before and after the deformation. When the gap is divergent(A-shaped), the film pressure decreases in the area of r smaller than R, and the film pressure increases in the area of r greater than R. With θ increasing, the minimum gas film thickness(h_min)decreases, and leakage(m)increases. When the gap is convergent(V-shaped), the film pressure increases in the area of r smaller than R, and decreases in the area of r greater than R. With θ increasing,the minimum gas film thickness(h_min)and leakage(m)decrease first and then increases.