飞轮轴系润滑剂损失及寿命分析

Analysis of Molecular Diffusion of Lubricants and Lubrication Life of Flywheel Shafting

空间卫星姿控飞轮支承轴承用液体润滑剂因真空挥发造成其质量损失,进而导致轴承润滑寿命和卫星运行寿命降低。为了研究润滑油蒸气的挥发损失及其对润滑寿命的影响,通过理论和实验验证润滑剂因分子流失对润滑寿命的影响,建立了轴承润滑油气物理模型,对该模型中的油蒸气分子通过密封间隙的迁移进行研究;通过中真空环境下的空间用润滑油长期挥发实验验证对润滑油蒸气分子迁移模型及损失率的分析。理论分析及实验结果表明,飞轮轴系油储年损失率小于1mg。优化密封设计参数、选用具有低饱和蒸汽压的润滑剂可有效降低润滑剂中基础油的挥发损失,提高轴系润滑寿命。

Liquid space lubricants used for bearings, which sustain the attitude control flywheel in satellite, are subjected to quality loss because of its volatilization ,and which can lead to the life reduced of the beating and satellite. In order to analyze the lubrication life of attitude control flywheel induced by the loss of lubrication oil vapor, a theoretical and experimental investigation was carried out to examine the influence of molecule escape on lubrication life. A physical mode of the lubrication was established, and the transfer of the oil molecule via the seal gap was studied. The transfer model and lose rate of the oil molecule were comparatively analyzed through the experiment that space lubricants volatilize long time in a middle vacuum room. The results indicate that the loss rate of the storage of experimental lubricant is less than 1 mg in a year. Optimizing the design parameters of the labyrinth seal and selecting the lubricants with lower saturated vapor pressure and molar mass can decrease the volatilization loss of the base oil, and increase the lubrication life of the shafting effectively.