600MW循环流化床锅炉水冷壁设置防磨梁后炉内气固流场的数值研究  

Numerical Study of Gas-Solid Flow Field in a 600 MW CFB Boiler with Anti-wear Beams

作　　者：夏云飞[1] 程乐鸣[1] 张俊春[1] 王勤辉[1] 方梦祥[1] 

机构地区：[1]浙江大学热能工程研究所能源清洁利用国家重点实验室,杭州310027

出　　处：《动力工程学报》2013年第2期81-87,共7页Journal of Chinese Society of Power Engineering

基　　金：国家"十二五"科技支撑计划资助项目(2012BAA02B01-03)

摘　　要：针对600MW裤衩腿循环流化床锅炉水冷壁壁面上设置与不设置多阶式防磨梁情况,采用数值模拟方法研究了防磨梁对炉内颗粒平均质量浓度和颗粒轴向速度、壁面区域颗粒浓度和轴向速度分布的影响,并综合分析了颗粒流对壁面磨损的影响.结果表明:防磨梁的存在削弱了炉膛颗粒轴向速度呈"M"型分布的趋势;水冷壁壁面设置防磨梁后,稀相区下部区域颗粒平均质量浓度略有减小,上部区域略有增大;防磨梁破坏了高质量浓度贴壁颗粒下降流,使得回流区厚度和颗粒下降速度减小,且越靠近壁面,这种影响越明显;2层防磨梁之间特别是防磨梁向炉内凸起的高度范围内,贴壁回流颗粒的质量浓度和下降速度增加速度均比无防磨梁时大;加装防磨梁后,贴壁颗粒流对壁面的磨损量总体上有所减小,但防磨梁附近壁面区域的磨损量相对较大.Numerical simulations were carried out to study the effect of anti-wear beams on the distribution of solids mass concentration and axial velocity both in the furnace and in the region close to the furnace wall in a 600 MW circulating fluidized bed （CFB） boiler with breeches legs, so as to comprehensively ana- lyze the influence of granular flow on the wall abrasion. Results show that the anti-wear beams weaken the M-shape distribution of solids axial velocity in the furnace; with anti-wear beams installed on the water wall, the average solids mass concentration decreases slightly in the lower dilute region but increases slightly in the upper dilute region. Anti-wear beams block the falling down of dense particles close to the wall, which reduce both the thickness of the return flow region and the falling velocity of particles, and the smaller the gap between granular flow and wall surface is, the more obvious the influence will be. Within the area between two anti-wear beams, especially within the range of beam height, the increase degree of mass concentration and falling velocity of particles adhering to the wall is higher than that without anti wear beams. For water walls protected with anti-wear beams, the total wall abrasion caused by adheringgranular flow is less than that without anti-wear beams; however, the local abrasion around anti-wear beams may be worse than that without anti-wear beams.

关 键 词：循环流化床锅炉 防磨梁 气固流场 数值模拟 

分 类 号：TK222[动力工程及工程热物理—动力机械及工程]