An Experimental Study of Transient Effects in Elastohydrodynamic Lubrication

轴承、齿轮和凸轮等机械部件构成了几乎所有机械系统的关键部件，包括电动马达、风力涡轮机、内燃机、直升机变速箱和电动汽车变速器等。这些部件的可靠和有效运行在很大程度上依赖于其摩擦部件之间是否存在厚度约为1微米的薄润滑膜。这种薄膜是通过弹性流体动力(EHD)润滑现象形成的。我们对弹性流体动力润滑的了解，以及我们在稳定条件下运行的触点中预测EHD膜厚度的能力是很好的。然而，在瞬变条件下，情况并非如此，因为施加的载荷、卷吸速度或润滑剂供应变化很快。该项目旨在使用高速光学干涉法来研究润滑膜在一系列瞬变条件下的行为。

Machine elements such as bearings, gears and cams form a key part of almost all mechanical systems including electric motors, wind turbines, internal combustion engines, helicopter gearboxes and EV transmissions to name a few. Reliable and efficient operation of these components is heavily dependent on the existence of thin lubricant films, of the order of 1 micron in thickness, between their rubbing parts. Such films are formed through a phenomenon of elastohydrodynamic (EHD) lubrication. Our understanding of elastohydrodynamic lubrication, and thus our ability to predict EHD film thickness, in contacts operating under steady conditions is well established. However, this is not the case under transient conditions, where the applied load, entrainment speed or lubricant supply changes rapidly. This project aims to use high-speed optical interferometry to investigate the behaviour of the lubricated film under a range of transient conditions.