直接空冷凝汽器单元内综合应用导流板和喷雾增湿的数值模拟

基于SIMPLE算法,采用k-ε模型,综合两相流,传热传质理论并结合实际运行对600 MW直接空冷机组空冷岛内一个单元进行了数值模拟,分析了综合应用内部导流板和喷雾增湿对空冷凝汽器压力的影响。结果表明:合理应用内部导流板能够增强喷雾增湿的冷却效果,更大程度地降低凝汽器压力;两导流板以对称方式布置在距离风机栈道中心线2.5 m位置,布置角度为70°(向外侧倾斜,与x轴所成锐角),宽度为1m;内外排喷嘴也以对称方式布置:外排喷嘴距离风机栈道中心线3.8 m,高度为0.7 m,喷雾方向为210°(在xy平面内与y轴正向所成角,逆时针旋转,下同),内排喷嘴距离风机栈道中心线2 m,高度为1.9 m,喷雾方向为60°时,凝汽器压力降幅最大,比不采取措施时降低了9.04 kPa,比单一应用喷雾增湿降低了0.87 kPa。

Numerical simulation of installation of the deflector and spray humidification in air-cooled condenser

With SIMPLE algorithm and k-ε model,applying the heat and mass transfer theory for two-phase of air and water,3D mathematical model of spray humidification system for 600 MW direct air-cooling unit was established and an analysis carried out to the influence of the deflector and spray humidification effect,Results show that: the reasonable application of the internal diversion device can enhance the cooling effect of spray humidifier,a greater degree of reduces the back pressure.Maximum pressure drop(9.04 kPa) is to be obtained under the deflector are arranged 2.5 m away to trestle center of air fan,angle 70°(inclined outward,to the x axis into acute angle),width for 1 m;the outer nozzles are symmetrically arranged 3.8 m away to trestle center of air fan,height is 0.7 m,the angle between nozzle direction and positive direction of y axis is 210°in the x y plane;inner nozzles are symmetrically arranged 2 m away to trestle center of air fan,nozzle height is 1.9 m;the angle between nozzle direction and positive direction of y axis is 60°in the xy plane.Than the single application spray humidifier reduces the 0.87 kPa.