摘要
以干气密封无限窄槽理论为基础,提出了不等温假设条件修正算法.利用机械密封端面温度分布近似算法求解干气密封端面温度分布函数,与液体介质情况不同的是,对于空气,其热传导角根据经验取为液体的3倍.为了更方便地求解Gabriel算法中的微分方程,采用线性曲线拟合方法获得与前面求得的温度分布函数近似的密封端面温径关系曲线T(r).将T(r)代入Gab-riel算法中代替原来的温度常量T,从而得到非等温条件下的螺旋槽干气密封端面压力分布微分方程.采用4阶龙格库塔法求解该微分方程,得到沿半径方向的端面压力分布.通过与文献结果对比发现,当膜厚分别为5.08,3.05,2.03μm时,采用非等温条件修正后的算法所得槽根处压力pg比原算法提高了6.8%,5.0%,2.7%.计算结果较好地反映了干气密封端面压力分布槽根处最高、外半径处次之、内半径处最小之一般规律.与有限元法相比,该算法应用更为便捷.
The analytical methods for estimating pressure distribution on the end face of a dry gas seal（DGS） were reviewed,and then a novel algorithm for non-isothermal conditions was proposed in this paper based on the Whipple infinite narrow-groove theory.The Tripp function was used to get a temperature profile along the radius on the end face.The heat conductivity angle of gas was selected to be 3 times the conductivity angle of liquid based on experience.To solve the adjusted Gabriel differential functions more conveniently,a curve fitting method was applied to obtain an approximate analytical function of temperature profile T（r）.The differential equations were solved by using 4th-order Rung-Kutta method.Compared with the results in literature,the pressures at groove bottom pg obtained by the present method are increased by 6.8%,5.0%,2.7% when the film thicknesses are 5.08,3.05,2.03 μm,respectively.And this result is consistent with the existing pressure distribution characteristic on a DGS end face.Compared with FEA（finite element analysis）,the present novel method can easily be applied in engineering.
出处
《排灌机械工程学报》
EI
北大核心
2013年第7期605-610,共6页
Journal of Drainage and Irrigation Machinery Engineering
基金
国家科技重大专项资金资助项目(2009ZX04014-102-03)
中央高校基本科研业务费专项资金资助项目(SWJTU09ZT06)
关键词
干气密封
端面温度
螺旋槽
端面压力
无限槽
dry gas seal
end face temperature
spiral groove
end face pressure
unlimited groove
