深度调峰运行下某CFBB水冷壁管热应力分析  

Thermal-stress Analysis of Water Wall Tubes of a CFBB Under Deep Peak Shaving Operation

作　　者：于涛 钱进[1] 王一桂 朱道兴 林志恒 罗芸 赵威 YU Tao;QIAN Jin;WANG Yigui;ZHU Daoxing;LIN Zhiheng;LUO Yun;ZHAO Wei(College of Electrical Engineering,Guizhou University,Guiyang 550025,China;Power China Guizhou Engineering Co.,Ltd,Guiyang 550025,China)

机构地区：[1]贵州大学电气工程学院,贵州贵阳550025 [2]中国电建集团贵州工程有限公司,贵州贵阳550025

出　　处：《贵州大学学报（自然科学版）》2023年第1期42-47,共6页Journal of Guizhou University:Natural Sciences

基　　金：贵州省科技支撑计划资助项目(黔科合支撑[2020]2Y040)。

摘　　要：随着大量新能源发电的并网,火电机组循环流化床锅炉(circulating fluidized bed boiler, CFBB)参与电网调峰时,机组的负荷在不断变化,机组的安全性受到了挑战,研究调峰时锅炉受热面管的温度与应力是必要的。通过数值模拟的方法对深度调峰运行下的二维膜式水冷壁管的温度、变形量和热应力进行分析。研究结果表明:CFBB深度调峰时热负荷由锅炉最大连续蒸发量(boiler maximum continuous rating, BMCR)至20%BMCR,膜式水冷壁管的温度、变形量和热应力都在逐渐减小;BMCR工况时,水冷壁管的温度、变形量和热应力最大分别为431.53℃、0.263 mm、131 MPa,均在水冷壁管材允许的范围内。热负荷由BMCR到20%BMCR和由20%BMCR到BMCR不断的调峰过程中,CFBB膜式水冷壁管的温度、变形量和热应力在不断交替变化,水冷壁管在交变的温度、变形量和热应力作用下疲劳损伤不断累积,最终因疲劳而失效。With the grid connection of a large number of new energy sources, when circulating fluidized bed boiler(CFBB) of thermal power unit is engaged in peak shaving, the load of the unit is constantly changing, and the safety of the unit is challenged. Therefore, it is necessary to study the temperature and stress of the heating surface tubes of the boiler during peak shaving. Through numerical simulation, the temperature, deformation and thermal stress of two-dimensional membrane wall tubes under deep peak-shaving operation are analyzed. The results show that the heat load under CFBB deep peak shaving increases from boiler maximum continuous rating(BMCR) to 20%BMCR, and the temperature, deformation and thermal stress of membrane wall tubes gradually decrease. Under the BMCR condition, the maximum temperature, deformation and thermal stress of the water-wall pipes are 431.53 ℃, 0.263 mm, and 131 MPa, respectively, all within the allowable range of the water-wall pipes. In the process of peak-shaving with the heat changing from BMCR to 20%BMCR and from 20%BMCR to BMCR, the temperature, deformation and thermal stress of CFBB membrane wall tubes are constantly changing alternately, and the fatigue damage of water-cooled wall tubes is constantly accumulating under the action of alternating temperature, deformation and thermal stress, and finally it fails due to fatigue.

关 键 词：数值模拟 深度调峰 循环流化床锅炉 膜式水冷壁管 热应力 

分 类 号：TK223.3[动力工程及工程热物理—动力机械及工程]