Analysis of Piston Slap-Induced Noise and Assessment of Some Methods of Control in Diesel Engines

In diesel engines with combustion-optimised for fuel consumption or emissions, mechanically-induced noise tends to control the overall engine noise level with that due to piston slap being predominant. Previous studies, mainly experimental, have helped to clarify the mechanism of the piston slap phenomenon and have suggested methods of control. This paper presents the latest results of a theoretical analysis of the piston slap dynamics which yields predictions of some optimum piston design features for low piston slap-induced noise related to the estimated mechanical efficiency of the engine.