微纳姿控飞轮油、脂润滑下功耗及寿命分析

Analysis of Power Loss and Life under Liquid and Grease Lubricating States for Micro-nano Attitude Control Wheel

为了满足体积小、质量轻的微纳姿控飞轮空间条间下长寿命的润滑要求,提出应用微量脂润滑的方式为微纳飞轮提供润滑,通过实验分析不同量油脂润滑下的功耗、温升变化、挥发率及寿命。结果显示:微纳姿控飞轮的轴承功耗和润滑剂的用量密切相关,减少润滑剂的用量可以使润滑剂的无用流动减小,功耗明显降低;微量脂润滑(脂用量占轴承空腔的30%)下的功耗小于油润滑下的功耗,且易于实现飞轮轴承的高精度稳速控制;脂润滑由于比油润滑的功耗大且脂热交换能力差,故温升比油润滑高,在飞轮典型的3000～6000r/min的工作转速范围内,微量脂润滑下的温升为5.2～8.5℃;真空条件下微量脂润滑条件下润滑脂的挥发损失率随时间而减小,最终稳定在一很小的挥发值,完全能够满足空间条件下微纳卫星的寿命要求。

In order to meet the lubrication life requirement of micro-nano satellite in space, a method using little grease lubrication for the macro-nano attitude control wheel was proposed.The power loss,temperature rising,lubrication loss and lubricating life with little grease lubrication （the grease dosage equals the 30% of bearing cavity） were analyzed.The results show that the power loss reduces with decreasing lubrication dosage.The power loss is less and the temperature rising is greater with little grease lubrication than with oil lubrication.The temperature rising with little grease lubrication is from 5.2 to 8.5 ℃ when the rotating speed of bearing is from 3 000 to 6 000 r/min.The lubrication loss of little grease under the condition of vacuum decreases with time increasing and then stabilizes at a very small value.The method with little grease lubrication for the macro-nano attitude control wheel is feasible.