卧式旋风燃烧器燃烧特性数值模拟研究  

Numerical Simulation of Combustion Characteristics of Horizontal Cyclone Burner

作　　者：任志远 樊俊杰[1] 陈松林 REN Zhi-yuan;FAN Jun-jie;CHEN Song-lin(School of Environment and Architecture,University of Shanghai for Science and Technology)

机构地区：[1]上海理工大学环境与建筑学院,上海200093

出　　处：《电站系统工程》2021年第4期25-28,32,共5页Power System Engineering

摘　　要：以某液态排渣卧式旋风燃烧器为研究对象,对卧式旋风燃烧器内燃烧特性进行了数值模拟研究,分析了燃烧器旋风筒几何结构尺寸及二次风布置方式对燃烧特性的影响。结果表明,旋风燃烧器的旋风筒长度及尾部缩口直径对燃烧器燃烧特性影响明显,旋风筒长度及尾部缩口直径过长或过短,均会影响煤粉停留时间及旋风筒外圈气流大小,进而影响燃烧器燃烧强度及整体温度水平;本次数值模拟工况下,旋风筒最佳相对长度Lx/Dx=1.3,旋风筒缩口直径相对长度ds/Dx=0.4;二次风布置相对位置旋风筒内流场起主导作用,二次风布置离旋风筒前锥角越远,卷吸回流较弱,燃烧强度较弱,因此升温较慢;尾部回流因二次风喷口后移而加强,燃烧强度大高温区前移,整体温度水平下降,因此二次风布置位置相对靠前燃烧强度及整体温度水平更有益。The combustion characteristics of the cyclone burner are simulated by CFD fluent solver, the influence of the geometry size of the cyclone and the arrangement of the secondary air on the combustion characteristics is analyzed. The length of the cyclone and the diameter of the tail crater have obvious influence on the combustion characteristics of the burner. If the length of the cyclone and the diameter of the tail crater are too long or too short, they will affect the residence time of the pulverized coal and the air flow size of the outer ring of the cyclone, thus reducing the combustion intensity and the overall temperature level of the burner. Under this numerical simulation condition, the best relative length of the cyclone Lx/Dx=1.3, rotation Diameter and relative length of air duct necking ds/Dx= 0.4, The arrangement of secondary air plays a leading role in the internal flow field of the cyclone. The farther away the arrangement of secondary air is from the front cone angle of the cyclone, the weaker the entrainment and return flow, the weaker the combustion intensity, so the slower the temperature rise.

关 键 词：旋风燃烧器 液态排渣 燃烧特性 数值模拟 

分 类 号：TK223[动力工程及工程热物理—动力机械及工程]