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汽油模型化合物的高频往复试验机 ( HFRR)试验表明 ,汽油主成分的粘度对磨损的影响可能比其化合物类型的影响还要大。这可能反映了 HFRR试验中粘度对汽油弹性流体润滑膜的形成的贡献。为了进一步研究汽油的润滑行为 ,测量了汽油及 MTBE的弹流润滑牵引力和油膜厚度 ,考察作为粘度最低的液体燃料的汽油生成的弹流膜究竟有多薄 ,以及如何由弹流润滑向边界润滑转变。结果表明 ,在高速下汽油、MTBE及柴油的弹流行为均遵循 Hamrock-Dowsen公式 ,而在低速下汽油的弹流膜极薄 ,在薄膜润滑区其弹流行为明显偏离理论直线。微牵引力试验台架试验表明 ,柴油的弹流润滑行为与十六烷和润滑油相似 ,而汽油和 MTBE则有很大的不同。在固定滑滚比下 ,汽油和 MTBE在低滚动速度下的摩擦系数很高 ,但在很高速度下的摩擦系数却降到比柴油和矿物润滑油更低的水平。可变滑滚比试验表明 ,在线性区 ,汽油的摩擦系数对滑滚比的增加十分敏感。对于汽油和MTBE,由于粘度太低以及目前的牵引力试验台滚动速度的限制 ,无法进入全膜润滑区 ,因此无法得到完整的Stribeck曲线。
High-frequency reciprocating testing machine (HFRR) tests on gasoline model compounds show that the viscosity of the main component of gasoline may have a greater influence on wear than the type of compound. This may reflect the contribution of viscosity in the HFRR test to the formation of gasoline-elastic fluid-lubricated membranes. In order to further study the lubricating behavior of gasoline, the lubrication and drag of gasoline and MTBE were measured, and how thin the elastic film generated by gasoline as the liquid fuel with the lowest viscosity and how to lubricate it from boundary to boundary change. The results show that the elastohydrodynamics of gasoline, MTBE and diesel follow the Hamrock-Dowsen equation at high speed, while the elastohydrodynamics of gasoline is very thin at low speed. The elastic behavior of gasoline in the film lubrication area deviates significantly from the theoretical one. Micro-traction test bench tests show that the ebullation behavior of diesel is similar to that of cetane and lubricants, while gasoline and MTBE are quite different. At a fixed slip ratio, the coefficient of friction of gasoline and MTBE at low rolling speeds is high, but at very high speeds the coefficient of friction drops to a lower level than diesel and mineral oils. The variable slip ratio test shows that in the linear region, the friction coefficient of gasoline is very sensitive to the increase of the slip ratio. For gasoline and MTBE, a complete Stribeck curve can not be obtained due to the low viscosities and the limitations of the current traction test bed rolling speed, which can not enter the full film lubrication zone.