柴油荷电雾滴薄片剥离式破碎模型研究  

Study on Charged Diesel Droplet Strip Break-up Model

作　　者：王贞涛[1,2] 王军锋[1] 闻建龙[1] 顾利平[2] 

机构地区：[1]江苏大学能源与动力工程学院,镇江212013 [2]江苏太湖锅炉股份有限公司博士后科研工作站,无锡214187

出　　处：《内燃机工程》2014年第3期94-99,共6页Chinese Internal Combustion Engine Engineering

基　　金：国家自然科学基金资助项目(51106064;51006047);中国博士后科学基金项目(2012M511214);江苏省博士后基金项目(1101149C);江苏高校优势学科建设工程项目(苏教财[2011]8号)

摘　　要：燃油静电喷雾技术可以提高柴油的雾化性能，并能降低废气的排放。通过理论分析研究了柴油荷电雾滴薄片剥离式静电破碎，并采用已有试验结果进行验证。在考虑韦伯数和雷诺数影响下，通过瑞利极限分析了影响柴油雾滴破碎的主要影响因素，并计算了雾滴静电薄片剥离式破碎的临界荷质比，其临界荷质比的数量级约为10^-6～10^-5C／g，而在试验室获得的雾滴粒径范围内其荷质比式验值数量级为10^-6C／g。研究结果表明：在静电场作用下雾滴带有净电荷或者极化电荷，柴油雾滴以薄片剥离式破碎发生了瑞利破碎与泰勒破碎，试验数据与理论分析值较为接近，为柴油雾滴在低压下的静电破碎提供了有力依据。同时，柴油荷电雾滴发生破碎后其数密度大量增加，雾滴间产生聚并趋势，雾滴容易结并因而索太尔平均直径出现峰值，使雾滴粒径与荷电电压呈现非单调性曲线关系。Charged diesel droplet strip breakup was theoretically reseached and verified by existent experimental results. The main factors affecting the droplet strip breakup were analyzed by adopting Rayleigh limit and considering effect of We and Re Numbers. The critical specific charge of droplets was calculated and its order of magnitude of 10^-6-10^-5 C/g was obtained. In the droplet range of experiments, the order of magnitude of experimental charge-to-mass ratio was 10^-6 C/g. Results indicate that the diesel droplet carrying net charge or polarized charge breakups into more fine drops with strip breakup model in Rayleigh mode and Taylor mode. The experimental results and the calculated data are quite close. This study can provide important foundation for realization of the fuel droplet low pressure atomization. When droplets breaking up, diesel droplet number density dramatically increases and the finer droplets coalesce, causing Sauter mean diameter （SMD） of droplets arriving to peak value. So the relation between the droplet size and charged voltage exhibits non-monotony.

关 键 词：内燃机 柴油 静电雾化 薄片剥离式 静电破碎 荷质比 雾滴粒径 

分 类 号：TK421.43[动力工程及工程热物理—动力机械及工程]