Abstract:Currently, studies on aerostatic dry gas seals are mostly limited to their steady characteristics, while little attention has been paid on their unsteady characteristics, which are very important to allow the seals to have excellent operating performance so far. Hence the aerostatic dry gas film pressure governing equations and unsteady Reynolds equations are solved by using small perturbation and finite difference methods under the condition of three degrees of freedom perturbation. The influences of squeeze number, frequency number and supplying gas pressure on the unsteady characteristics are investigated. The results show that the axial direct dynamic gas film stiffness increases with increasing squeeze number, frequency number and supplying gas pressure, but the direct dynamic gas film stiffness in two angular directions is little influenced by the squeeze number. The axial direct damping coefficient and direct damping coefficients in two angular directions decrease with increasing squeeze number and supplying gas pressure. The axial direct damping coefficient decreases fast when the squeeze number is less than 20. The cross coupled dynamic stiffness and damping coefficients of two angular directions have an axisymmetric feature. The coupled dynamic stiffness and damping coefficients have a little relation with squeeze number when the number is in the range of 1-40, but increase with the increasing number if the number is larger than 40.
许恒杰, 宋鹏云. 三自由度微扰下的静压干气密封动态特性分析[J]. 排灌机械工程学报, 2017, 35(1): 56-64.
XU Hengjie, SONG Pengyun. Analysis on dynamic characteristics of aerostatic dry gas seals with three degrees of freedom perturbation. Journal of Drainage and Irrigation Machinery Engin, 2017, 35(1): 56-64.
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