哈尔滨工程大学学报2018，Vol.39Issue(5)：949-954,6.DOI:10.11990/jheu.201611038
喷射压力对喷孔流量及内部空化的影响
Influence of inlet pressure on flow rate and internal cavitation of nozzle
摘要
Abstract
Flow is an important parameter in the evaluation of injector performance.To investigate the effect of in-jection pressure on discharge,along with performing a computational fluid dynamics(CFD)three-dimensional sim-ulation,we built a scale-hole injector nozzle to investigate the effect of the inlet pressure of a diesel nozzle on flow. We analyzed the variation law of cavitation flow inside the nozzle with changes in inlet pressure and the effect of cavitation flow on the flow of fuel oil inside the nozzle.The results show that, as the outlet backpressure remains constant with increases in inlet pressure, cavitation occurs at the nozzle entrance and develops toward the outlet. When the cavitation area at the inlet section reaches its maximum value, it holds constant and the fuel mass flow rate steadily increases.The development process of the discharge coefficient(Cd)can be divided into three stages:at Pin<0.8 MPa,Cdis constant and related only to the nozzle structure;at 0.8 MPa<Pin<1.8 MPa,Cdsharply decreases and is related only to the shrinkage coefficient and cavitation number in the inlet section; at Pin>1.8 MPa,Cdis related to the cavitation number;as the inlet pressure continues to increase,the cavitation number ap-proaches 1 and Cdtends to become increasingly stable.关键词
柴油机/喷孔/入口压力/空化/流量特性/等效压力/比例放大/计算流体力学Key words
diesel engine/nozzle/inlet pressure/cavitation/flow characteristics/equivalent pressure/scaling up/computational fluid dynamics(CFD)分类
能源科技引用本文复制引用
雷艳,高壮,仇滔,宋鑫..喷射压力对喷孔流量及内部空化的影响[J].哈尔滨工程大学学报,2018,39(5):949-954,6.基金项目
国家自然科学基金项目(51006012) （51006012）
北京市教育委员会科学与技术发展项目(KM201610005018,KM201310005033). （KM201610005018,KM201310005033）
