%A SONG Pengyun, LI Ying, MA Ailinª¤ %T An approximate analytical method of gas film pressure in non-parallel gap of spiral groove dry gas seal %0 Journal Article %D 2015 %J Journal of Drainage and Irrigation Machinery Engin %R 10.3969/j.issn.1674-8530.15.0081 %P 1049-1055 %V 33 %N 12 %U {http://zzs.ujs.edu.cn/pgjx/CN/abstract/article_1967.shtml} %8 2015-12-25 %X 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 ¦È increasing, the minimum gas film thickness(hmin)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 ¦È increasing,the minimum gas film thickness(hmin)and leakage(m)decrease first and then increases.ª¤