首页> 外文期刊>大气科学进展(英文版) >Large Eddy Simulation and Study of the Urban Boundary Layer
【24h】

Large Eddy Simulation and Study of the Urban Boundary Layer

机译:大涡模拟与城市边界层研究

获取原文
获取原文并翻译 | 示例
       

摘要

Based on a pseudo-spectral large eddy simulation (LES) model, an LES model with an anisotropy turbulent kinetic energy (TKE) closure model and an explicit multi-stage third-order Runge-Kutta scheme is established. The modeling and analysis show that the LES model can simulate the planetary boundary layer (PBL) with a uniform underlying surface under various stratifications very well. Then, similar to the description of a forest canopy, the drag term on momentum and the production term of TKE by subgrid city buildings are introduced into the LES equations to account for the area-averaged effect of the subgrid urban canopy elements and to simulate the meteorological fields of the urban boundary layer (UBL). Numerical experiments and comparison analysis show that: (1) the result from the LES of the UBL with a proposed formula for the drag coefficient is consistent and comparable with that from wind tunnel experiments and an urban subdomain scale model; (2) due to the effect of urban buildings, the wind velocity near the canopy is decreased, turbulence is intensified, TKE, variance, and momentum flux are increased, the momentum and heat flux at the top of the PBL are increased, and the development of the PBL is quickened; (3) the height of the roughness sublayer (RS) of the actual city buildings is the maximum building height (1.5-3 times the mean building height), and a constant flux layer (CFL) exists in the lower part of the UBL.
机译:基于伪谱大涡模拟(LES)模型,建立了具有各向异性湍动能(TKE)闭合模型和显式多级三阶Runge-Kutta格式的LES模型。建模和分析表明,LES模型可以很好地模拟各种分层条件下具有均匀下垫面的行星边界层(PBL)。然后,类似于森林冠层的描述,将亚网格城市建筑物的动量阻力项和TKE的生产项引入LES方程,以说明亚网格城市冠层单元的面积平均效应并模拟城市边界层(UBL)的气象领域。数值实验和比较分析表明:(1)提出了阻力系数公式的UBL的LES结果与风洞试验和城市子域尺度模型的结果一致且可比; (2)由于城市建筑的影响,冠层附近的风速降低,湍流加剧,TKE,方差和动量通量增加,PBL顶部的动量和热通量增加,并且加快PBL的发展; (3)实际城市建筑物的粗糙度子层(RS)的高度是最大建筑物高度(平均建筑物高度的1.5-3倍),并且UBL的下部存在恒定的通量层(CFL)。

著录项

获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号