直接空冷凝汽器喷雾增湿系统的结构优化  

Structural Optimization for Spray Humidification System of a Direct Air-cooled Condenser

作　　者：周兰欣[1] 张情[1] 李卫华[1] 

机构地区：[1]华北电力大学电站设备状态监测与控制教育部重点实验室,保定071003

出　　处：《动力工程学报》2011年第2期148-152,共5页Journal of Chinese Society of Power Engineering

摘　　要：应用气水两相流的传热传质理论,建立了600 MW直接空冷机组空冷凝汽器喷雾增湿系统三维数学模型,利用CFD软件对该系统进行了数值摸拟,并分析了在喷嘴纵向布置时,喷嘴布置高度、喷雾方向、喷雾压力及喷嘴孔径对喷雾增湿效果的影响.结果表明:当喷嘴孔径越小、喷嘴流量越少时,空冷单元内所需的喷嘴数就越多,且雾滴雾化的细度越小,越有利于雾滴的均匀分布及其在空冷单元内的充满度,对喷雾增湿的效果越明显.当喷嘴孔径为0.4 m、喷雾压力为1.2 MPa、喷嘴以对称方式距风机栈桥中心线4 m、喷嘴高度为0.3 m及喷嘴方向在xy平面内与y轴正方向夹角为120°时,凝汽器压力降幅最大,比喷雾前降低了8.84 kPa.Applying the heat and mass transfer theory for air-water two-phase flow,a 3D mathematical model of spray humidification system for a 600 MW direct air-cooling unit has been established,with which a numerical simulation for the system performed using CFD software and an analysis carried out to the influence of nozzle height,nozzle orientation,spray pressure and nozzle diameter on the spray humidification effect,in a longitudinal nozzle arrangement.Results show that the smaller the nozzle size and flow rate are,the more the number of nozzles will be required,and the finer the atomized droplet size will be produced,resulting in even distribution of droplets,high degree of droplet filling in the air-cooled unit and therefore obvious humidification effect.Maximum pressure drop（8.84 kPa） is to be obtained under the premise that the nozzle size is 0.4 m,spray pressure is 1.2 MPa,nozzles are symmetrically arranged 4 m away to trestle center of air fan,nozzle height is 0.3 m and the angle between nozzle direction and positive direction of y axis is 120° in the xy plane.

关 键 词：直接空冷凝汽器 空冷机组 喷雾增湿系统 喷嘴布置 结构优化 

分 类 号：TK264.11[动力工程及工程热物理—动力机械及工程]