空冷岛对底层大气边界层特性的影响

摘要

利用Gambit软件建立空冷岛模型,通过UDF加载大气边界层函数,并针对不同温度层结设置不同的温度分布函数,利用Fluent软件模拟并分析空冷岛对局地环境的影响,得到空冷岛周围区域不同高度处的风速和温度值,结合风切变理论和Monin-Obukhov相似理论计算空冷岛周围动量通量和热量通量的变化.结果表明:随着风速的增大,风切变指数会略微增大,且沿流向逐渐减小;空冷岛对动量通量和热量通量的影响沿流向逐渐减小,且稳定层结下的影响小于不稳定层结下的影响,即使在稳定层结下,空冷岛周围动量通量和热量通量的变化程度亦均大于其他区域动量通量和热量通量的变化程度.%A model of air cooling island was established with Gambit software by numerical method,with which,the effects of air cooling island on the local environment were analyzed using Fluent software by loading atmospheric boundary layer function through UDF and setting temperature distribution function for different temperature stratifications,so as to obtain the wind velocity and temperature at different heights in the area around the air cooling island,and to study the change trend of momentum flux and heat flux based on wind shear theory and Monin-Obukhov similarity theory.Results show that with the rise of wind velocity,the wind shear increases slightly,which reduces gradually along the flow direction.The influence of air cooling island on the momentum flux and heat flux reduces along the flow direction,while the influence on stable stratification is less than that on unstable stratification,and the influence degree on stable stratification is higher than on any other places except for the unstable stratification.