Cavitation failure analysis and mechanism study of the wet cylinder liner in heavy-duty diesel engines

Abstract

Cavitation failure of the cylinder liner is one of the main reliability problems in heavy-duty diesel engines. It can shorten engine lifespan, increase maintenance costs, and even lead to catastrophic failures. This paper conducts a systematic study of cylinder liner cavitation by integrating microstructure analysis, cavitation process observation, and numerical simulation. The morphology and chemical composition of the damaged regions are analysed at both macro and micro levels, providing comprehensive insights into the cavitation erosion behaviour and damage mechanisms. The vibration and pressure fluctuation characteristics of the cylinder liner-water jacket system are investigated by a structure-acoustic coupling model. The predicted cavitation risk regions of the cylinder liner are in good agreement with the actual cavitation erosion regions. Cavitation damage is primarily concentrated within a 26 mm vertical zone adjacent to the lower seal of the cylinder liner. The minimum pressure in the water jacket occurs at 373.3 °CA. When the engine speed exceeds 1400 rpm, the risk of cavitation arises and progressively intensifies with increasing speed and load. The results enrich the theoretical system of cavitation erosion in cylinder liners and provide a valuable reference for the cavitation prediction and mitigation.