基于激光诱导炽光法的柴油喷雾燃烧碳烟生成特性  

Characteristic of Diesel Spray Combustion and Soot Formation Using Laser-Induced Incandescence

作　　者：陈亮[1] 成晓北[1] 颜方沁[1] 郑亮[2] 王志[2] 

机构地区：[1]华中科技大学能源与动力工程学院,湖北武汉430074 [2]清华大学汽车安全与节能国家重点实验室,北京100084

出　　处：《内燃机学报》2012年第5期390-396,共7页Transactions of Csice

基　　金：国家自然科学基金资助项目(50976039);清华大学汽车安全与节能国家重点实验室开放基金资助项目(KF10112)

摘　　要：采用激光诱导炽光法(LII),对高温高压定容燃烧弹内柴油喷雾燃烧火焰及碳烟生成的二维分布图像进行了测量分析,研究了在不同定容室环境温度、环境压力和喷射压力下燃烧火焰和油气混合特性对碳烟生成与分布的影响规律.结果表明:柴油燃料滞燃期会随环境温度和环境压力的升高而缩短;扩散燃烧火焰的浮起长度内空气卷吸量是影响碳烟形成过程的一个重要因素,高的环境温度和环境压力,以及低的喷油压力会产生较短的柴油火焰浮起长度;高的柴油喷射压力、低的环境压力和温度所产生的LII信号强度较弱,即此时激光片光内的碳烟体积分数较小.在喷雾混合中自然形成的混合气浓度分层和温度分层,既影响到混合气的着火和燃烧过程,又诱发碳烟颗粒的产生,研究结果对优化燃烧系统设计,验证燃烧模型提供了有价值的依据.The planar distribution images of diesel spray combustion flame and soot formation were meas- ured and analyzed by using laser-induced incandescence （LⅡ）, in a high-temperature high-pressure con- stant volume combustion bomb. The effects of combustion flame and fuel gas mixing characteristics on soot formation and distribution was studied, under different ambient condition of constant volume com- bustion bomb and injection pressure. Result indicates that, with increasing ambient temperature and pres- sure, the ignition delay of diesel fuel becomes shorter. Air entrainment in the diffusion combustion flame lift-off is one of the most important factors affecting soot formation and evolution. Increasing ambient temperature and pressure and decreasing injection pressure shorten the diesel flame lift-off. High injection pressure and low ambient temperature and pressure generate low LⅡ signal intensity, indicating small soot volume fraction. Naturally forming mixture concentration and temperature stratification in spray mix- ing process influence not only on ignition and combustion processes, but also soot formation. The study provides valuable basis for optimization design of combustion system and verification of combustion mod- els.

关 键 词：激光诱导炽光法 定容燃烧弹 火焰浮起长度 碳烟体积分数 

分 类 号：TK401[动力工程及工程热物理—动力机械及工程]