利用k-ε湍流能量闭合方法对城市街渠内气流结构的模拟

Simulations for flow structures in city canyon with k-ε turbulence energy closure scheme

利用非静力、能量闭合的大气边界层模式分别对二维情况下不同高宽比的街渠内部的气流结构和三维情况下城市街渠在来流方向不同的条件下的内部气流结构进行了数值模拟。并且对三维情况下街渠的上风向建筑物顶部的风向与街渠中心近地面的风向之间的关系和街渠内部上层的风向与街渠中心近地面的风向之间的关系进行了模拟研究 ,将这些结果与GTJohnson等人的现场观测和模式模拟结果进行了比较 ,表明两者有较好的一致性。

A nonhydrostatic atmospheric boundary layer model with an energy closure scheme( k～ε ) is used to simulate the flow structures in 2 D and 3 D city canyons.These flow structures are analyzed and the relation between θ roof (wind direction over the upwind building) and θ canyon (wind direction in canyon bottom) and that between θ top (wind direction at the top of canyon) and θ canyon are investigated.Those results are compared with the results observed and simulated by G T Johnson et al in 1993.It indicates that this model does well in simulating the flow structures in city canyons.