四角切圆锅炉炉内燃烧数值模拟  

Numerical simulation of combustion process in a tangentially pulverized-coal-fired boiler under variable load operation

作　　者：王秋红[1] 王超 张小桃[1] 王爱军[1] 屈士玺 

机构地区：[1]华北水利水电大学电力学院,河南郑州450011 [2]新乡航空工业(集团)有限公司,河南新乡453049 [3]山东电力工程咨询院有限公司,山东济南25000

出　　处：《热力发电》2016年第9期61-66,共6页Thermal Power Generation

基　　金：河南省高等学校重点科研资助计划项目(15A470018)

摘　　要：为了研究不同负荷下炉内燃烧及污染物排放情况,基于Fluent软件对某台350MW四角切圆燃烧锅炉进行数值模拟,分析随着锅炉负荷的变化,炉内的流场、温度场、组分分布及污染物NO_x质量浓度分布。结果表明:炉内切圆明显,整个炉膛空间存在螺旋上升的流场;燃烧器区域温度最高,炉内温度随着炉膛高度增加而降低;随着负荷降低,炉内温度水平降低,30%额定负荷工况时炉内温度水平偏低,需要考虑炉内煤粉的引燃和稳燃问题;组分场分布与温度场有很大关系,高温区对应高CO浓度场和低CO_2浓度场;在炉膛高温区大量生成热力型NO_x,随着锅炉负荷降低,炉膛出口NO_x质量浓度逐渐降低。In order to study the combustion process and NO_x emission of supercritical 350 MW unit boilers,the Fluent software was applied to carry out numerical simulation on a 350 MW tangentially coal-fired boiler.The aerodynamic field,temperature field,component field and the NOxdistribution under variable load operation were analyzed.The simulation results indicate that,the tangential circle can be seen obviously and the aerodynamic field is swirling from bottom to top in the furnace.The temperature reaches the highest around the burner areas,it decreases with the increasing furnace height.The temperature difference in the burner zone is 352 Kfrom the BMCR condition to the 30% THA condition.At 30% THA condition,the temperature level in the furnace is low,so the ignition and combustion stabilization need to be considered.The component field is strongly related to the temperature field,the high temperature area corresponds to high CO and low CO_2 concentration.NOxis generated in great quantities in the highest temperature field.The NOxconcentration at the furnace outlet decreases gradually with the unit load.

关 键 词：锅炉 燃烧器 四角切圆 燃烧 NOX排放 温度场 组分场 数值模拟 

分 类 号：TK16[动力工程及工程热物理—热能工程]