This study proposes a tribo-dynamic model for point contacts under lubrication, focusing on the excitations caused by surface movement, defect and load impact. Surface movement and load impact can cause changes in contact force, resulting in acceleration and dynamic displacement, which may affect the flow of the lubricant. The traditional lubrication model is usually steady or transient, and load balance is used to correct the normal height, ignoring a series of influences such as the mass, stiffness and damping. It requires repeated corrections to obtain a balanced position, which is very time-consuming. By combining tribology and dynamics, dynamic excitation is introduced in the contact process in this study. After determining the initial value, the normal height can be directly obtained from the dynamic equation. Besides, a comparison between the tribo-dynamic model and the steady-state model is presented. It is found that the film thickness and pressure distribution calculated by the two models are almost the same at medium and low speeds, while the calculation results of the two models are different at high speed or under load impact, which emphasises the importance of considering the dynamic behaviour in the study of contacts.

中文翻译：

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润滑下点接触的摩擦动力学模型

本研究提出了润滑下点接触的摩擦动力学模型，重点关注由表面运动、缺陷和负载冲击引起的激励。表面运动和载荷冲击会引起接触力的变化，从而产生加速度和动态位移，从而可能影响润滑剂的流动。传统的润滑模型通常是稳态的或瞬态的，采用负载平衡来修正正常高度，忽略了质量、刚度和阻尼等一系列影响。需要反复修正以获得平衡位置，非常耗时。本研究通过结合摩擦学和动力学，在接触过程中引入了动态激励。确定初始值后，法线高度可以直接从动力学方程中得到。除了，摩擦动力学模型和稳态模型之间的比较被提出。发现两种模型计算的油膜厚度和压力分布在中低速时几乎相同，而两种模型在高速或负载冲击时的计算结果不同，强调考虑接触研究中的动态行为。