【摘要】 提出了曲柄销轴承表面不同微结构的设计方法,以改善发动机的润滑和摩擦性能.以油膜压力、摩擦力、表面凹凸接触力和曲柄销轴承的摩擦系数为目标函数,基于曲柄销轴承流体动力润滑模型对发动机2 000 r/min下轴承表面布置楔形纹理、方形纹理、圆形纹理及方-圆形组合纹理等不同微结构的润滑和摩擦特性进行了模拟和评估.结果表明,与楔形纹理、方形纹理及方-圆形组合纹理结构相比,轴承表面方形纹理微结构设计可显著提高曲柄销轴承的润滑和摩擦性能.摩擦力、表面凹凸接触力和曲柄销轴承的摩擦系数的平均值比仅对曲柄销轴承尺寸优化分别降低了28.5%、14.5%和33.2%,比仅做圆形纹理微结构设计分别降低了34.4%、26.3%和43.6%.因此,对曲柄销轴承表面进行方形纹理微结构设计可有效提高发动机的润滑和摩擦性能.更多还原

【Abstract】 A design of different microtextures on the surface of the crankpin bearing(CB) is proposed to ameliorate the lubrication and friction performance(LFP) of engines. On the basis of the CB’s hydrodynamic lubrication model, the bearing surface of CB using different microtextures, such as wedge-shaped textures(WSTs), square textures(STs), circular textures(CTs), and combined square-circular textures(CSCTs), is simulated and assessed under various external loads of the CB at an engine speed of 2 000 r/min. The pressure of the oil film, the frictional force, the force of the solid asperity contact, and the friction coefficient of the CB are used as objective functions. Results indicate that the bearing surface designed by the STs remarkably improves the CB’s LFP in comparison with other structures of WSTs, CTs, and CSCTs. Particularly, the average values of the frictional force, solid asperity contact, and friction coefficient of the CB using the STs are greatly reduced by 28.5%, 14.5%, and 33.2% and by 34.4%, 26.3%, and 43.6% in comparison with the optimized CB dimensions and CTs, respectively. Therefore, the application of the STs on the CB surfaces can enhance the LFP of engines.更多还原