亚临界煤粉锅炉流体流动和燃烧的数值模拟  

Numerical Simulation of Fluid Flow and Combustion in a Subcritical Pulverized Coal Boiler

作　　者：马爱纯[1] 董红莉[1] 王莹[1] 周孑民[1] 朱再兴[1] 

机构地区：[1]中南大学能源科学与工程学院,长沙410083

出　　处：《武汉理工大学学报》2012年第1期66-70,共5页Journal of Wuhan University of Technology

基　　金：国家自然科学基金(50876116)

摘　　要：以一300MW Hg1025/18.2-YM13型亚临界自然循环、四角切圆燃煤锅炉为研究对象,应用可实现化k-ε湍流模型、颗粒相随机轨道模型、即混即燃气相燃烧模型、P-1辐射换热模型,根据燃烧测试试验得到的边界条件,运用FLUENT软件对锅炉炉内流体流动和燃烧过程进行了三维数值研究。模拟预测结果与试验结果吻合较好,温度分布规律和趋势与试验研究结果一致。运用该模型对炉内速度场、压力场、温度场以及燃烧释热场进行了多场耦合仿真,并全面系统地研究了各种操作参数对炉内燃烧工况的定量影响规律,确定了燃烧器和锅炉合理的操作参数:过剩空气系数为1.2、一次风率为20%、一次风温度为608K、二次风温度为620K且均匀投粉。在该条件下炉内温度分布较合理,煤粉能正常稳定地燃烧,炉膛高温区较集中,炉膛出口温度合理。A 300 MW Hg1025/18.2-YM13 sub-critical natural circulation tangentially corner-fired boiler was investigated in this paper.A three-dimensional numerical study on fluid flow and combustion in this boiler was undertaken by using realizable k-ε turbulent model,stochastic trajectory model for particle phase,non-premixed combustion model,P-1 radiation model and commercial CFD software Fluent 6.3.The simulation results agree well with measurements,and the velocity distribution trends are consistent with the experimental results.The velocity profile,pressure profile and temperature profile in the boiler were calculated and the effects of some operational parameters on combustion process in the boiler were analyzed.Optimal operational parameters for the burner and boiler were determined as excess air coefficient of 1.2,the ratio of primary air of 20%,the temperature of primary air of 608 K,the temperature of secondary air of 620 K and uniformly coal powder jetting.In this case,the temperature profile in the boiler is reasonable and the coal can combust normally and stably.The high temperature zone is concentrated in the boiler center near the burners and the exhaust gas temperature at the furnace exit is reasonable.

关 键 词：四角切圆锅炉 煤粉燃烧器 数值仿真 FLUENT 参数优化 

分 类 号：TK223[动力工程及工程热物理—动力机械及工程]