Experimental Research on Idle Combustion Noise of a Diesel Engine

Abstract

Noise is one of the three major pollutants in the world, among which noise pollution complaints caused by fuel-powered vehicles account for more than 70%. Research on engine combustion noise is aimed at reducing pollution problems caused by it. Based on the Chinese national standard ‘Reciprocating internal combustion engines-Measurement method for combustion noise’, an experimental study on combustion noise of a certain type of diesel engine under idling conditions was carried out. In the test, by changing the calibration values of the engine, such as: pre-injection mass, rail pressure and other calibration parameters, the cylinder pressure at idle speed of the engine is calculated based on the theory of cylinder force. It is concluded that when the rotational speed is 750r/min, the increase of the pre-injection amount and the rail pressure leads to an increase in the mean value of the combustion parameters of each cylinder force stage and is concentrated in the high frequency part. This study provides a reference for optimizing the idling noise of diesel engines, which is conducive to reducing noise pollution in life.