空化现象在流体动压润滑中常见而又重要，空化的产生通常会造成润滑膜的破裂，影响润滑性能，甚至引起气蚀。这在柴油发动机连杆轴承中尤其需要关注，因此对其空化特性进行准确模拟具有重要意义。该文基于AVL-EXCITE软件平台，建立了发动机的柔性多体动力学耦合弹性流体动压润滑（EHL）仿真模型。结果表明，连杆大端轴承在做功冲程中空化区域在出口区，呈"手指形"分布，并且轴径油孔快速经过空化区域，可能会导致空化区域内的气泡破裂，发生气蚀。这为气蚀位点的预测提供了一种潜在的方法。此外，还考察了润滑油黏度和供油压强对空化特性的影响，指出适当提高润滑油黏度及供油压强可减缓空化效应。
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.
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