Numerical investigation of the cavitation damage in a high performance engine conrod big end bearing via a mass-conserving complementarity algorithm

The object of the study is the conrod big end bearing of an high performance motorbike engine. Comparative analyses involving different geometrical configurations of the crankpin/conrod assemblies, and in particular of different shapes of the inner profile of the bearing, are presented. The influence of the properties of the lubricant is also discussed. A preliminary cavitation damage index is proposed based on the variation in time of the void fraction at a certain location. The results obtained show a strong influence of the geometry of the bearing on the cavitation phenomenon. Experimental evidence qualitatively agrees with numerical forecasts, thus corroborating the use of both the methodology and the cavitation damage index proposed in this contribution.