Cavitation characterization simulation in connecting-rod bearings based on AVL-EXCITE
LI Xinxin1, DU Xiangning2, LI Yuanzhe1, CAO Hengchao2, TIAN Yu1
1. State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China; 2. Weichai Power Co., Ltd., Weifang 261061, China
Abstract：Cavitation is common and important in hydrodynamic lubrication that generally causes the rupture of lubrication film and affects the performance of the lubrication, which even leads to cavitation erosion in some situations. This is especially important in connecting-rod bearings in diesel engines. Thus, accurately characterizing cavitation is of great significance. Herein, a multi-body dynamic model of an engine considering elastohydrodynamic lubrication (EHL) was established based on the AVL-EXCITE software platform. According to the EHL results, a finger-like cavitation region in the big-end bearing of the connecting rod was distributed in the lubrication outlet during the work stroke. Meanwhile, the cavitation bubbles in the cavitation region might collapse and result in cavitation erosion when the oil supply bore passed through. This provides a potential method to predict the occurrence of cavitation erosion. Furthermore, the influences of lubricating-oil viscosity and oil-supply pressure on cavitation characteristics were investigated. An appropriate increase in these two parameters can slow down the cavitation effect.
李新新, 杜祥宁, 李远哲, 曹恒超, 田煜. 基于AVL-EXCITE的发动机连杆轴承空化特性模拟[J]. 清华大学学报（自然科学版）, 2022, 62(3): 385-390,399.
LI Xinxin, DU Xiangning, LI Yuanzhe, CAO Hengchao, TIAN Yu. Cavitation characterization simulation in connecting-rod bearings based on AVL-EXCITE. Journal of Tsinghua University(Science and Technology), 2022, 62(3): 385-390,399.
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2022, Vol. 62 
