王咏薇,蒋维楣. 2009. 多层城市冠层模式的建立及数值试验研究[J]. 气象学报, 67(6):1013-1024, doi:10.11676/qxxb2009.098
多层城市冠层模式的建立及数值试验研究
Numerical study on development of a multil ayer urban canopy model
投稿时间:2009-03-31  修订日期:2009-06-11
DOI:10.11676/qxxb2009.098
中文关键词:  多层城市冠层模式,城市地表辐射收支,拖曳力,建筑物形态学特征
英文关键词:Multi layer urban canopy model, Urban radiation process, Drag force, Buildings complex surface
基金项目:国家自然科学重点基金项目(40333027),国家自然科学基金项目(40775014),中国博士后基金项目(20090451234)
作者单位
王咏薇 南京信息工程大学气象灾害省部共建教育部重点实验室南京210044南京大学大气科学学院南京210093 
蒋维楣 南京大学大气科学学院南京210093 
摘要点击次数: 2968
全文下载次数: 2516
中文摘要:
      为在城市气象数值模拟中更好地体现由城市发展引起的下垫面土地利用改变及人 为活动对大气过程的影响,建立了基于建筑物三维分布的多层城市冠层模式,冠层内动 力方程组考虑了建筑物冠层拖曳力的作用及雷诺应力的影响,通过引入建筑物宽度、间距以 及垂直分布密度指数等建筑物形态特征参数,以更好地体现城市复杂地表对大气温度、湿度 及动量方程的影响。同时,该模式分屋顶、4个侧壁及地面分别考虑辐射及能量平衡求解 表面温度,计算各表面与大气的通量交换,并考虑辐射阴影效应、冠层内部各个面之间的可视因子、以及与冠层内建筑物密度指数、可视因子等相关的多重反射辐射导致的辐射截陷作用。模式的离线检验结果表明:(1)冠层模式计算风廓线与风洞实验测量数据吻合良好;(2)离线冠层模式能够模拟实际小区的风速、温度垂直廓线,并能够较好地体现小区内气 温日变化。冠层模式与区域边界层模式耦合检验结果表明:(1)耦合模拟的近地面(2 m处)气温及地表温度的结果明显优于传统的水泥平板方案,尤其是在夜间,水泥平板方案 与实测气温最大偏差4 K左右,耦合模拟方案为1—2 K;(2)耦合模拟方案考虑了建筑物 对冠层之上的拖曳力影响以及建筑物形态结构对雷诺应力的影响,风速(10 m处)计算结果 与观测值相差约在1 m/s,水泥平板方案偏差3 m/s左右。
英文摘要:
      Based on the assumption of 3 dimension building geometry, a multiplayer urban c anopy model were developed to research the relationship between atm ospheric movement and the urban developing. The canopy model, which consists of a set of dynamic equations with a drag force, and there are three major paramete rs: building width, distance between buildings, and vertical floor density distr ibution, which is the distribution of a ratio of the number of the buildings tha t are taller than some level to all the buildings in the urban area under consid eration. In addition, an irradiative process in the canopy is introduced, in whi ch the model geometry is assumed to be an infinitely extended regular array of u niform buildings in the horizontal, each of which is composed of six faces (roof , floor, and four vertical walls). Both of the drag force of the buildings and t he irradiative process, including the radiation shadowing and trapping effect, d epend on the floor density distribution in the vertical. The off line validation of the canopy model shows that the simulation is agr eed with wind tunnel test data and the observation data in sub domain very well . As a new urban land surface scheme, the canopy model was then coupled with Re gional Boundary Layer Model of Nanjing University(NJU RBLM), and on line cas es were performed for 4 August 2004 in Beijing city. The simulation result comp ared with observations from a dense operational observational network. The compa rison result shows that the coupled scheme (MUCM case) correctly reproduces t he temperature (within 1-2 K difference from the observations) and wind spee d(about 1 m/s difference from the observations), and is better than the soil veg etation modified scheme (SLAB case), especially for temperature simulation in ni ght time. Besides, the comparison of ground surface temperature between simulated and observed results by Landsat satellite shows that the new urban land surfa ce process scheme improved the simulation performance at urban underplaying rema rkably for taking care of the more reasonable radiation process in three dimen sion buildings structure.
HTML   查看全文   查看/发表评论  下载PDF阅读器
分享按钮