往复式骨架油封密封界面内油膜压力和厚度分布

Distribution of Film Pressure and Thickness in the Sealing Interface of Reciprocating Skeleton Oil Seal

以汽车减震器密封用的往复式骨架油封为研究对象,基于润滑理论建立密封界面内的流体润滑数值计算模型来分析往复式骨架油封的密封性能,该模型耦合了固体力学、流体力学以及变形力学分析。采用ANSYS有限元分析提取密封区的静接触压力进行固体力学分析,采用超松弛迭代法求解雷诺方程进行流体力学分析,采用影响系数法求解密封唇面的变形,其中假定密封唇面的微凹凸形貌具有正弦和双余弦分布。通过模型分析密封唇面微凹凸形貌、往复速度对密封界面内的油膜压力和厚度的影响规律。结果表明:在2种不同形式的密封唇面微凹凸形貌下,内行程中密封界面内的油膜压力大于外行程的;密封唇面微凹凸形貌以正弦函数分布,往复式骨架油封密封处发生泄漏;密封唇面微凹凸形貌以双余弦函数分布,往复式骨架油封具有良好的密封性能。

The reciprocating skeleton oil seal used for automobile shock absorber seal was taken as the research object.Based on the lubrication theory,the numerical simulation model of fluid lubrication in the sealing interface was established to analyze the sealing performance of reciprocating skeleton oil seal.The model was coupled with solid mechanics,fluid mechanics and deformation mechanics analysis.The static contact pressure of sealing zone was extracted by ANSYS finite element for solid mechanics analysis.The Reynolds equation was solved by over relaxation iteration method for hydrodynamics analysis.The influence coefficient method was adopted to solve the deformation of sealing lip.The micro-asperity shape of sealing lip was assumed to have sine and double cosine distribution.The influence of micro-asperity shape distribution and reciprocating speed on the film pressure and thickness was analyzed based on the model.The results show that the the film pressure during the instroke is greater than that during the outstroke under the two different forms of micro-asperity shape of sealing lip.When the micro-asperity shape of sealing lip is distributed as sinusoidal function,the leakage appears in the lip of the reciprocating skeleton oil seal.When the micro-asperity shape of sealing lip is distributed as double cosine function,the reciprocating skeleton oil seal has good sealing performance.