喷雾撞壁后近壁区域火焰发展及碳烟生成研究  

Study of Flame Development and Soot Formation in the Near Wall Region After Spray Impingement

作　　者：覃文[1] 马天宇 丰雷 王浒[2] 尧命发[2] 张岩 QIN Wen;MA Tian-Yu;FENG Lei;WANG Hu;YAO Ming-Fa;ZHANG Yan(Guangxi Yuchai Machinery Co.,Ltd.,Yulin 537005,China;State Key Laboratory of Engines,Tianjin University,Tianjin 300350,China;China North Engine Research Institute,Tianjin 300400,China)

机构地区：[1]广西玉柴机器股份有限公司,玉林537005 [2]天津大学内燃机燃烧学国家重点实验室,天津300072 [3]中国北方发动机研究所,天津300400

出　　处：《工程热物理学报》2020年第5期1247-1253,共7页Journal of Engineering Thermophysics

基　　金：国家自然科学基金项目(No.51876140,No.91541111)。

摘　　要：本文基于多尺度液滴撞壁形态提出了新的考虑了不同飞溅状态的撞壁模型。结合容弹实验研究了近壁区域喷雾撞壁后火焰发展过程,对影响近壁区燃烧过程及碳烟生成规律的边界温度进行了探讨。结果表明,环境温度和壁面温度对喷雾撞壁后的液膜沉积量以及后续的燃烧过程影响显著。碳烟产生峰值直接和壁面燃油沉积量呈正相关,而较高的近壁区域温度可加速燃油蒸发并减少燃油沉积量。燃油沉积量的不同,其火焰发展形式不同:当沉积燃油较少时,近壁混合气形成较快,从而维持了稳定的燃烧过程;而当沉积燃油较多时,近壁区域的燃烧呈现不稳定的池火过程。随着环境温度和壁温的增加,油膜燃烧时刻提前并形成可燃混合气,从而加速了碳烟的生成和氧化。The effects of near wall region temperature conditions on fuel combustion and soot formation after spray wall impingement were studied based on both newly developed spray impact model and experiments in a constant volume vessel.The result indicates that the ambient temperature and wall temperature greatly affects the fuel film deposition and the combustion process.Higher temperature could accelerate fuel evaporation and reduce fuel deposition.The peak soot production increase linearly with the deposited film mass.Different near wall combustion processes are found based on different deposited film mass.For insignificant fuel deposition case,stable flame was formed based on fast mixture formation process.For significant wall film case,a typical pool fire phenomenon can be observed.Higher ambient and wall temperature accelerates the evaporation and products high temperature mixture in the near wall region,results in faster soot oxidation.

关 键 词：喷雾撞壁 火焰 碳烟 

分 类 号：TK412[动力工程及工程热物理—动力机械及工程]