燃油喷嘴结构参数对空化性能的影响研究

A Study of the Effect of Fuel Nozzle Structural Parameters on Cavitation Performance

柴油机喷嘴内的空化对柴油机的性能会产生严重影响,一方面他能促进燃油的雾化,使得燃油在发动机内部能高效、充分地燃烧,降低了积炭产生的可能;另一方面空化能引起喷嘴内部的空蚀磨损,从而影响喷嘴的使用寿命与性能.通过计算流体力学,采用VOF模型加空化模型研究喷嘴的结构参数对空化性能的影响.采用无量纲量的方法,对气液进口夹角比、气液进口长度比,气液进口直径比3个无量纲量进行分析.为以后研究气液两相燃油喷嘴燃油雾化特性提供理论基础.

Cavitation in the diesel nozzle can have a serious impact on the performance of the diesel engine.On the one hand,it promotes the atomisation of the fuel,enabling efficient and sufficient combustion of the fuel inside the engine and reducing the possibility of carbon build-up.On the other hand cavitation can cause cavitation wear inside the nozzle,thus affecting the life and performance of the nozzle.This paper investigates the effect of nozzle structural parameters on cavitation performance through computational fluid dynamics using a VOF model plus a cavitation model.Three dimensionless quantities,the gas-liquid inlet angle ratio,the gas-liquid inlet length ratio,and the gas-liquid inlet diameter ratio,are analysed using the dimensionless quantity method.To provide a theoretical basis for future research into the fuel atomisation characteristics of gas-liquid two-phase fuel nozzles.