早喷参数对燃油湿壁影响的数值模拟  

Numerical Simulation of Effect of Early Injection Parameters on Spray-Wall Impingement

作　　者：于晗正男[1] 梁兴雨[1] 王月森[1] 王翔翔 

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072 [2]联合汽车电子有限公司,上海201206

出　　处：《燃烧科学与技术》2016年第1期20-25,共6页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(51376136);天津市自然科学基金资助项目(14JCYBJC21300)

摘　　要：利用AVL-Fire软件建立了4100柴油机的三维数值模型,并对早喷策略下燃油喷雾湿壁现象进行了数值模拟,重点研究了早喷参数(喷油时刻、喷雾锥角、喷油压力及两段喷射)对早喷阶段累积燃油撞壁量、最大湿壁油膜质量和主喷开始前残余湿壁油膜质量等燃油湿壁参数的影响.研究表明:早喷时刻对燃油湿壁量影响不大;喷油压力对喷雾到达壁面时间和缸内气流运动均产生影响;减小喷雾锥角、采用两段式早喷策略可以有效降低燃油湿壁量,但改变两段喷油量的比例对改善燃油湿壁作用不大.A three-dimensional model of 4100 diesel engine was established using the AVL-Fire code.The spray-wall impingement phenomenon with early injection strategy was numerically investigated.The effects of early injection parameters（injection timing,spray cone angle,injection pressure and two-stage injection strategy）on the accumulated mass of spray-wall impingement,the maximum mass of wall film and the residual mass of wall film before the main injection were studied.Results showed that the injection timing hardly affected the mass of spray-wall impingement.Both the time of the spray reaching the cylinder wall and the charge motion in the cylinder were affected by the injection pressure.Decreasing the spray cone angle and using the two-stage early injection strategy were proved to be useful approaches to reducing spray-wall impingement,while changing the fuel injection ratio of the two-stage strategy was not effective enough for reducing spray-wall impingement.

关 键 词：柴油机 低温燃烧 早喷 燃油湿壁 数值模拟 

分 类 号：TK448.21[动力工程及工程热物理—动力机械及工程]