Abnormal film shapes in sliding elastohydrodynamic contacts lubricated by fatty alcohols
Abnormal film shapes in sliding elastohydrodynamic contacts lubricated by fatty alcohols
复制标题
DOI：
10.1243/13506501jet253
复制
发表时间：
2007-03
期刊：
影响因子：
--
通讯作者：
K. Yagi;P. Vergne
中科院分区：
文献类型：
--
作者：
K. Yagi;P. Vergne
本文描述了脂肪醇润滑点滑动接触中的异常油膜形状。使用粘度和压粘系数较低的月桂醇和1-十二烷醇作为润滑剂，在中等膜厚条件下出现了原始膜厚特征。薄膜厚度的测量是通过白光干涉法应用于玻璃盘钢球接触。当滑辊比增加时，膜厚分布发生变化。厚度增加可导致比在纯轧制条件下测量的值高几倍的值。保持平均夹带速度恒定，尽管相同的绝对值的滑动辊比，膜厚度分布时，球速度较高时的盘速度较高时的不同。使用文献结果和一个简单的热模型，估计在固体表面和油膜的温度增加的机制，可以解释这样一个新的和意想不到的弹流润滑膜的行为进行了讨论。根据模型的结果，它的结论是，无论是温度升高，也不是固体表面之间的温差可以解释的异常膜厚特征的外观。然而，流体响应之间的差异表明，润滑剂的流变行为有助于对所观察到的现象。
Abstract This paper describes abnormal film shapes in point sliding contacts lubricated by fatty alcohols. The original film thickness features have appeared under moderate film thickness conditions using lauric alcohol and 1-dodecanol, which have a low viscosity and pressure-viscosity coefficient as lubricants. The film thickness is measured by white-light interferometry applied to glass disc-steel ball contacts. When the slide to roll ratio increases, the film thickness distribution changes. The thickness increase can lead to values several times higher than those measured under pure rolling conditions. Keeping the mean entrainment speed constant, despite the same absolute values of the slide to roll ratios, the film thickness distributions when the ball speed is higher differ from those when the disc speed is higher. The mechanisms that can explain such a new and unexpected EHL film behaviour are discussed using literature results and a simple thermal model that estimates the temperature increase at the solid surfaces and oil film. According to the results of the model, it is concluded that neither the temperature increase nor the temperature difference between the solid surfaces can explain the appearance of the abnormal film thickness features. However, the differences between the fluid responses suggest that the lubricant rheological behaviour contributes towards the observed phenomena.