The prediction of lubrication performance is required to be the basement of friction optimization for marine engines. This paper simulates the lubrication performance of marine engines based on statistical models which have the advantages of fast, efficient, and macroscopic fault location. Boundary lubrication exists in the piston ring-cylinder liner (PRCL) of two-stroke marine engines because of the harsher load, lower speed, and larger structure. It has been proposed that there would be tribofilm under boundary lubrication which has a significant influence on the contact. To understand the boundary lubrication, it is necessary to study the lubrication regime transition. In this paper, firstly, the coefficient of friction curve combined with the thickness ratio embodies the lubrication regime transition process of two-stroke engines under work conditions. However, the phenomenon that the coefficients under boundary lubrication are smaller than that of other regimes shows the non-objectivity of this curve. Therefore, the Stribeck curve is introduced for objectively evaluating the transition. Then, the calculation of asperities contact pressure under boundary lubrication, which Wen proposed, is introduced into the classic Greenwood-Williamson model, the problem that the original model cannot reflect the boundary lubrication regime in the form of the Stribeck curve is improved. Finally, the results are compared before and after modifying the model to verify this study’s practicability. It provides more precise asperities contact pressure for the tribofilm growth calculation from the perspective of the Stribeck curve under the PRCL statistical model in future work.

润滑性能的预测是船用发动机摩擦优化的基础。本文基于统计模型模拟船用发动机的润滑性能，具有快速、高效、宏观故障定位等优点。二冲程船用发动机的活塞环-缸套（PRCL）由于载荷较重、转速较低、结构较大，因此存在边界润滑。有人提出在边界润滑下会有摩擦膜，这对接触有重大影响。为了理解边界润滑，有必要研究润滑状态的转变。在本文中，首先，摩擦系数曲线结合厚度比，体现了二冲程发动机在工况下的润滑状态转变过程。然而，边界润滑下的系数小于其他状态的现象表明该曲线的非客观性。因此，引入 Stribeck 曲线是为了客观评估过渡。然后，将文提出的边界润滑下粗糙面接触压力的计算引入到经典的Greenwood-Williamson模型中，改善了原有模型不能以Stribeck曲线的形式反映边界润滑状态的问题。最后，通过对模型修改前后的结果进行对比，验证了本研究的实用性。