基于区域嵌套与分解的城市风环境模拟方法

Numerical Simulation Method for Urban Wind Environment Based on Regional Nestification and Split

提出了适合城市风环境数值模拟的一个新的计算方法——嵌套计算方法。该方法首先对目标建筑群及其更大的周边环境建立大计算域并以较粗的网格进行计算,然后建立包含目标建筑群的子计算域并以精细的网格划分,以大计算域计算出的解作为子计算域的边界条件以实现区域嵌套求解。通过对两种建筑群布局的模拟计算,将该方法与传统方法计算的高精度解和中精度解进行对比。结果表明,可以降低单次计算的网格数量,并且计算结果具有较高的精确度。

A novel calculation of the simulation for urban wind environment is proposed called the nested calculation. In this calculation,the first step is to solve the entire computational domain including the targeted building cluster and the surrounding environment with coarse grids,which is less accuracy. The next step is to build the computational sub-domain not including the surrounding environment with fine grids and solve it using the boundary conditions predicted by the results from the first step. Taking two layouts of building clusters as cases studies,the nested calculation is evaluated by comparisons with traditional calculations which directly solve the entire computational domain with fine grids and critical grids respectively. Results indicate that the method presented in the paper can reduce the grids number in single calculation. And the nested calculation show fairly high accuracy.