Identification of combustion noise

Abstract

Noise is unpleasant sound that can have harmful effect on people’s health. Motor vehicles and working machines are mobile sources of noise, in which engine is one of the key elements that create noise. Engine noise can be divided into mechanical noise and combustion noise. Diesel engines are always considered to be louder, and, as such, they are used to identify engine combustion noise. Increase of pressure in engine cylinder is typical for combustion noise. Based on this, an experiment was performed, during which a cylinder pressure and noise emitted by the engine were simultaneously recorded. By coherence analysis of acquired data, it was concluded that it is possible to separate engine combustion noise from mechanical noise of the engine.