超高层建筑施工中氨气抑制的数值模拟

针对超高层建筑施工中典型空气污染物氨气，运用CFD方法构建武汉中心三维立体模型，模拟标准k ε条件下自然通风和机械通风2种抑制措施对氨气浓度整体影响效果并确定其影响进深。结果表明:稳态下机械通风对降低模型整体氨气浓度效果有限，单个送风口沿送风方向影响进深约为6.1 m，垂直于风速方向约为1.2 m，且送风口影响进深随风速变化极小；自然通风对降低模型整体氨气浓度效果明显，进风口对氨气浓度影响进深约为17.5 m，随高度增加逐渐递增的进风速度在通风前15 s对氨气浓度影响明显，稳态时风速增加自然通风影响进深增加有限；施工中可主要采用自然通风抑制氨污染，幕墙封闭后可利用机械通风并辅以导风板等设施提高机械通风影响效果。

Numerical Simulation of Inhibition of Ammonia in Construction of Super High rise Building

Aiming at the ammonia of typical air pollutant in construction of super high rise building, the three dimensional model of Wuhan center was constructed by using CFD method. The standard k-εcondition was simulated, and the whole effect on ammonia concentration and influence depths through two suppression measures of natural and mechanical ventilations were analyzed. The results show that the effect of mechanical ventilation on reducing the whole ammonia concentration is limited under steady state. The influence depth of a single air supply outlet is about 6.1 m along the direction of air supply, and 1.2 m perpendicular to the direction of air supply. The influence depth changes little with the wind velocity. The effect of natural ventilation on reducing the whole ammonia concentration is obvious, and the influence depth of air supply outlet is about 17.5 m. The increasing wind velocity with the height has obvious influence on ammonia concentration in initial 15 s, while the influence distance of natural ventilation increases limited with rising velocity under steady state. The natural ventilation is the mainly method to inhibit ammonia pollution in construction, and mechanical ventilation along with air deflector and other facilities can be used to improve the effect of mechanical ventilation after curtain wall construction.