城市街区流场和污染物扩散的数值模拟研究  

Numerical simulation of air flow and pollutant dispersion in urban street canyons

作　　者：张莹[1] 邵毅[1,2] 王式功[1] 

机构地区：[1]兰州大学大气科学学院,甘肃省干旱气候变化与减灾重点实验室,甘肃兰州730000 [2]95639部队气象台,四川绵阳621000

出　　处：《环境污染与防治》2016年第4期6-11,共6页Environmental Pollution & Control

基　　金：国家自然科学基金资助项目(No.41105109);公益性行业(气象)科研专项(No.GYHY201106034);国家人口健康科学数据共享平台(No.2005PKA32400);兰州大学中央高校基本科研业务费专项资金资助项目(No.lzujbky-2013-m03)

摘　　要：利用天气预报(WRF)模式提供边界条件和初始条件驱动Fluent模式,模拟了榆中县城市区域的大气流动和污染物扩散。WRF模式在一定误差要求下对研究区域的基本气象要素的模拟准确率均在70%以上,较为准确地模拟气象要素实况,为Fluent模式提供了可靠的初始条件和边界条件;Fluent模式充分刻画了复杂城市下垫面的建筑物对污染物扩散的影响,较好地反映了不同区域污染物浓度差异;通过WRF-Fluent耦合模式的模拟,显示有建筑群存在的城市环境中,流场相对于环境风产生显著改变,进而反映建筑群中污染物的复杂扩散形态。结果表明,WRF-Fluent耦合模式作为一种研究城市建筑密集区域的大气流动状态和污染物扩散过程的方法是可行的。Flow and pollutant dispersion in urban street canyons of Yuzhong,Gansu,were simulated by using Fluent model with initial conditions and boundary conditions provided by WRF（Weather Research and Forecast）model.Simulation results showed that WRF model simulated weather situation and meteorological elements were well matched with the observed ones.In addition,the accuracy of simulated meteorological elements were all above 70%compared with observed ones.That was to say WRF model could provide initial conditions and boundary conditions for Fluent model.Fluent model could characterize the impact of a building complex urban surface diffusion of pollutants,to better reflect regional differences in the concentration of pollutants.Results from the coupled WRF-Fluent model simulation showed that the flow in building clusters could change significantly with ambient wind,and then complicated dispersion of pollutant.Result of present study suggested that the coupled WRF-Fluent model was an important tool that could be used for studying and simulating urban flow and dispersion in densely built-up area.

关 键 词：WRF模式 Fluent模式 流场 污染物扩散 

分 类 号：X51[环境科学与工程—环境工程]