天然气发动机预燃室内混合气形成对点火射流的影响  

Effects of Mixture Formation in Pre-Combustion Chamber on Ignition and Combustion of a Natural Gas Engine

作　　者：曹阳[1] 朱启天 周逸帆 魏震鸿 刘瑞 张玉银[1] CAO Yang;ZHU Qitian;ZHOU Yifan;WEI Zhenhong;LIU Rui;ZHANG Yuyin(School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Shanghai Marine Diesel Engine Research Institute,Shanghai 201108,China)

机构地区：[1]上海交通大学机械与动力工程学院,上海200240 [2]中国船舶集团有限公司第七一一研究所,上海201108

出　　处：《内燃机工程》2022年第4期31-39,共9页Chinese Internal Combustion Engine Engineering

基　　金：国家自然科学基金项目(52176168)。

摘　　要：针对船用天然气发动机预燃室内的混合气形成及射流点火特性进行了研究。基于试验标定和验证的喷雾燃烧模型,对预燃室内的柴油雾化–混合–着火过程进行了仿真计算,获得了混合气形成对点火射流特性的影响规律。结果表明,在同时考虑预燃室内燃油湿壁量与雾化质量时,存在一个最佳喷射压力匹配区间,且在相同喷射压力下采用两段喷射可以减少预燃室的燃油湿壁量;增大预燃室内混合气浓度分层并缩短初始着火点与射流孔的距离,可减小燃料损失,增长放热持续期,提高点火能力。The mixture formation and turbulent jet ignition characteristics in the pre-combustion chamber(PCC) of a marine natural gas engine was studied.Based on the experimentally calibrated spray model,the simulation of the diesel atomization–mixing–ignition process in the PCC was carried out,and the influence law of the injection parameters and the pre-chamber structure parameters on the ignition characteristics was obtained.Results show that the injection pressure affects the formation of the mixture in the PPC from aspects of both the wet wall and atomization.The use of two-stage injection can reduce the fuel amount of wet wall in the PPC.When the mixture just starts to catch fire,increasing the equivalence ratio gradient of the mixture and shortening the distance between the initial ignition point and the jet hole can reduce fuel loss,increase the duration of heat release and improve the ignition ability.

关 键 词：天然气发动机 预燃室点火 混合气形成 多指标综合评价法 

分 类 号：TK411.2[动力工程及工程热物理—动力机械及工程]