A modified energy-based model for describing wear processes applied to an internal combustion engine

Abstract

To describe and predict wear in a tribosystem, theoretical wear formulas and empirical models exist. Most of the existing formulations have a short range of validity and can only be applied for a specific contact situation. In this paper, the aim is to investigate a specific technical application of a tribocontact in an internal combustion engine. In particular, the contact between a piston skirt and a cylinder liner is experimentally simulated using a linear reciprocating tribometer and original engine parts, under closeto-reality loading conditions. The experimental findings will be analysed with a wear model that is most applicable to the actual tribosystem. This wear model, which is based on a combination of energy theories and a molecular mechanics approach, will be extended in the paper in order to add surface topography relevant parameters. The modified wear model is capable of combining the prediction of wear volume loss with the theory of fatigue and can be applied to any kind of tribosystems suffering damage due to reciprocating relative motion. For comparison with classical wear models, an empirical power law – including Archard as a special case – is shown. Using the measurement results of the tribometer, the parameters that are specific to the aforementioned wear model are determined. Further more, the applicability of the used model to describe the wear processes in this specific tribosystem will be discussed.