烟气横掠麻面管束颗粒沉积特性的数值分析  

Numerical Analysis on Particle Deposition Characteristics of Flue Gas Flowing Across Pitted Tubes in Aligned Arrangement

作　　者：闫顺林[1] 王皓轩[1] 

机构地区：[1]华北电力大学能源动力与机械工程学院,河北保定071003

出　　处：《电力科学与工程》2017年第11期66-72,共7页Electric Power Science and Engineering

摘　　要：为了减轻电厂锅炉尾道内烟气对换热管的磨损及积灰情况,特提出和建立了一种新型的管型——麻面管,并通过选择适用的磨损计算和颗粒沉积模型,针对烟气横掠顺列麻面管束进行气固两相流动的数值模拟,分析了烟气物性参数和管束结构参数对颗粒沉积特性的影响,并比较了相同条件下麻面管和光管的积灰情况。结果表明:等同工况下,麻面管表面颗粒沉积率和磨损量均比光管的低;较大烟速情况下,随着颗粒平均粒径的增大,磨损增加幅度较大;确定了当s1/D=3.0,s2/D=1.8时,颗粒沉积率最低,为20.72%;对于一般的较小粒径颗粒,e=0.75 mm的麻面管管束在减轻积灰上效果较其他几种情况更好,另外,麻面管表面坑深度越大,飞灰颗粒对麻面管的磨损就越轻。In order to reduce the erosion and relieve the ash accumulation of heat exchange tube in boiler onomichi of power plant, the pitted tube, a new type of tube, is put forward and established in this paper. By choosing a suitable wear calculation and a particle deposition model, this paper carries on the numerical simulation of gas-solid flow on the basis of flue gas flowing cross pitted tubes in aligned arrangement; and the effects of the smoke＇ s physical parameters and tubes＇ s structural parameters on the pitted tubes＇ s particle deposition characteristics are analyzed, and the rough and smooth tube＇ s deposition under the same conditions are compared. The results show that the particle deposition rate and the wear of pitted tube＇ s surface are lower than those of the light tube under equivalent conditions. With the increase of the average particle size, the wear rate increases greatly under the condition of large smoke velocity; when s1/D =3.0, s2/D = 1.8, the particle deposition rate is the lowest, and it is 20. 72%. For the average small particle size, pitted tube with e = 0.75 mm is better than other kinds when it comes to the effect of relieving the ash accumula- tion. In addition, the greater the pipe surface pits＇ depth is, the lighter the wear is.

关 键 词：麻面管 气固两相流 颗粒沉积 磨损 数值模拟 

分 类 号：TK223.3[动力工程及工程热物理—动力机械及工程]