ABSTRACT The crankshaft is the core component of a piston engine. Once a bending deformation fault occurs in the crankshaft, it can cause serious damage to the safe operation of the entire engine. However, diagnostic methods for detecting this fault are rare. In this paper, the influence of a bending micro-deformation of the crankshaft (BMDC) on the gear transmission system (GTS) was studied through theoretical analysis and simulation calculation. A fault diagnosis method for the BMDC based on the axial force of the crankshaft and the radial displacement of the flywheel gear (RDFG) was proposed. A three-dimensional model of the GTS of a diesel engine was established. The impact of the BMDC on the gear train and the fluctuation of the RDFG were calculated through a multi-body dynamics simulation. Finally, a condition monitoring and fault diagnosis system (CMFDS) was built to monitor the engine, and the effectiveness of the proposed method was verified by fault instances.

中文翻译：

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活塞发动机曲轴弯曲微变形故障特征及诊断方法

【摘要】：曲轴是活塞发动机的核心部件。一旦曲轴发生弯曲变形故障，就会对整个发动机的安全运行造成严重损害。但是，用于检测此故障的诊断方法很少见。本文通过理论分析和仿真计算研究了曲轴弯曲微变形（BMDC）对齿轮传动系统（GTS）的影响。提出了一种基于曲轴轴向力和飞轮齿轮(RDFG)径向位移的BMDC故障诊断方法。建立了柴油机GTS的三维模型。通过多体动力学仿真计算了 BMDC 对齿轮系的影响和 RDFG 的波动。最后，