油雾旋流燃烧的实验和计算分析  

An Experimental and Computational Study of Spray Combustion in Swirling Flows

作　　者：刘镇剑 朱民[1] 李少帅[1] 

机构地区：[1]清华大学热能工程系热科学与动力工程教育部重点实验室,北京100084

出　　处：《热能动力工程》2016年第2期104-110,142,共7页Journal of Engineering for Thermal Energy and Power

摘　　要：为提高油雾旋流燃烧时燃烧效率,结合搭建实验台进行实验测量和建立数学模型模拟计算,研究了油雾旋流燃烧时旋流体对流场结构液滴蒸发和燃烧特性的影响。结果表明:旋流流场的结构主要可以分为中心回流区和两层螺旋涡结构,随着旋流数的增加,内层涡旋的强度增加,外层涡旋的强度降低。旋流数的增加还能促进液滴的扩散、蒸发以及液滴和空气掺混,使得燃烧室上游燃料浓度增加,燃烧效率提高。随着雷诺数的增加,中心回流区增加,火焰长度变短。In the energy and power systems,swirl-stabilized spray combustion is a common combustion strategy. How to further improve the combustion efficiency and reduce emissions is the core interest of basic research and technology development. In this article,we used both experiments and numerical simulations to analyze the influence of swirl on flow field structure,droplet evaporation and combustion characteristics. The structure of cyclone flow field can be divided into three parts: the central recirculation zone and two kinds of helical vortex,which structure is affected by swirl number. With the increase of swirl number,the inner vortex becomes stronger,while the outer vortex becomes weaker. With the help of swirl,the oil droplets spread outward,evaporate more quickly and mix with air more efficiently,leading to higher fuel concentration in upstream and higher combustion efficiency. With the increase of Reynolds number,the central recirculation zone increases gradually and the length of flame becomes shorter.

关 键 词：油雾旋流燃烧 旋流数 中心回流区 螺旋涡 液滴蒸发 数值计算 

分 类 号：TK16[动力工程及工程热物理—热能工程]