检验喷油嘴时清脆响声的产生与雾化的机理研究

Study on Mechanisms of Nozzle Spray Noise and Atomization

对两种不同密封座面直径的喷油嘴在手压式喷油器校验器上进行了对比试验 ,分析了喷油嘴检验时发出清脆响声的机理 ,以及响声清脆的喷油嘴其雾化看起来也较好的原因 ;同时在喷油泵工作转速为 10 0 0 r/ min时用内燃机激光全息照相系统测取了两种喷油嘴的喷雾特性 。

An investigation on spray noise of two nozzles with different diameter sealing seats was made through analyzing the signals of needle lift and noise of spray that were measured on a manual nozzle tester in time and frequency domains. The results show that a clear spray noise is caused by the oscillations of the needle that opens and closes at a high speed during operation. As a result, the atomization looks like better just because the high frequency oscillation of needle results in a high injection rate. Spraying characteristics of two different kinds of nozzles were also investigated by means of the laser holography at the injection pump speed of 1 000 r/min. The experimental results show that as the fuel injection rate of a manual tester is too low to reflect a real injection situation of the engine, the atomizing quality can not be estimated by a clear or unclear spray noise.