1000MW超临界塔式锅炉垂直水冷壁内工质流动与传热特性分析  

Analysis of Flow and Heat Transfer Characteristics of Working Medium in Vertical Water-Cooled Wall of a 1 000 MW Supercritical Tower Boiler

作　　者：郝小红[1] 杜肃 徐培星 马达夫 HAO Xiao-hong;DU Su;XU Pei-xing;MA Da-fu(College of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai,China,200093)

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《热能动力工程》2021年第2期86-92,122,共8页Journal of Engineering for Thermal Energy and Power

摘　　要：以某1 000 MW超临界塔式锅炉水冷壁垂直管圈为研究对象,根据半侧绝热、半侧变热流和Y型三通的边界条件建立三维模型,进行数值模拟。模拟结果表明:在100%BMCR工况下,垂直管圈中超临界水入口温度为718.8 K,出口温度为729.8 K。内壁面的温度和超临界水的流速会受到截面积的影响,截面减小使得内壁面温度降低,流速增加;分析了传热系数对体积比热容和轴向流速的影响,发现体积比热容和传热系数变化趋势一致,轴向流动会极大影响传热;并最终拟合出新的符合垂直水冷壁工况的Nu准则式。A 1 000 MW supercritical tower boiler water-cooled vertical pipe coil is taken as the research object for numerical simulation and a three-dimensional model is established based on the boundary conditions of half-side insulation,half-side variable heat flow,and the Y-shaped tube.Simulation results show that: under the 100% BMCR conditions,the inlet temperature of the supercritical water in the vertical pipe is 718.8 K and the outlet temperature is 729.8 K.The temperature of the inner wall surface and the flow velocity of the supercritical water are affected by the size of the cross-sectional area,the small cross-sectional area results in decrease in the inner wall surface temperature and increase in the flow velocity;After analyzing the relationship between the heat transfer coefficient and volume specific heat capacity and the axial flow velocity,It is found that the volume specific heat capacity and the heat transfer coefficient have a consistent trend,and axial flow will greatly affect heat transfer;Finally a new and fitting Nu criterion formula is determined for vertical water-cooled wall.

关 键 词：超临界锅炉 水动力特性 流量偏差 流场 温度场 

分 类 号：TK221[动力工程及工程热物理—动力机械及工程]