中国环境监测
中國環境鑑測
중국배경감측
ENVIRONMENTAL MONITORING IN CHINA
2014年
4期
93-99
,共7页
PM2?5%气象条件%空间形态
PM2?5%氣象條件%空間形態
PM2?5%기상조건%공간형태
PM2.5%meteorological condition%spatial morphology
2013年2月1日至3月20日、2013年7月10日至8月10日对成都市大气中细颗粒物( PM2?5)进行连续监测,同步记录气象数据。将PM2?5质量浓度与城市气象条件进行相关性分析,研究气象条件对PM2?5质量浓度的影响。2月1日至3月20日PM2?5质量浓度平均为147?38μg/m3,7月10日至8月10日平均为50?19μg/m3,大气细颗粒物污染最严重的时间出现在2月1-6日。成都市各气象条件中,PM2?5质量浓度与能见度、风速呈现显著负相关,而与其他气象要素相关性较弱,降水对PM2?5质量浓度影响也很大。改善城市通风有利于成都市大气中PM2?5的稀释和消散。通过建立3D模型并运用计算流体力学( CFD)软件模拟成都市选定的一处密集的建成区域,分析城市空间形态对通风的影响。研究发现,在假设等温的情况下,多层密集的区域对城市通风影响小,而高层对城市通风影响很大,建筑高度相近的街道与风向平行的风速大于与风向成角度的,与风向平行的街道沿线为高层的风速高于沿线为多层的,较大的开敞空间及背景风速更有利于城市通风环境。
2013年2月1日至3月20日、2013年7月10日至8月10日對成都市大氣中細顆粒物( PM2?5)進行連續鑑測,同步記錄氣象數據。將PM2?5質量濃度與城市氣象條件進行相關性分析,研究氣象條件對PM2?5質量濃度的影響。2月1日至3月20日PM2?5質量濃度平均為147?38μg/m3,7月10日至8月10日平均為50?19μg/m3,大氣細顆粒物汙染最嚴重的時間齣現在2月1-6日。成都市各氣象條件中,PM2?5質量濃度與能見度、風速呈現顯著負相關,而與其他氣象要素相關性較弱,降水對PM2?5質量濃度影響也很大。改善城市通風有利于成都市大氣中PM2?5的稀釋和消散。通過建立3D模型併運用計算流體力學( CFD)軟件模擬成都市選定的一處密集的建成區域,分析城市空間形態對通風的影響。研究髮現,在假設等溫的情況下,多層密集的區域對城市通風影響小,而高層對城市通風影響很大,建築高度相近的街道與風嚮平行的風速大于與風嚮成角度的,與風嚮平行的街道沿線為高層的風速高于沿線為多層的,較大的開敞空間及揹景風速更有利于城市通風環境。
2013년2월1일지3월20일、2013년7월10일지8월10일대성도시대기중세과립물( PM2?5)진행련속감측,동보기록기상수거。장PM2?5질량농도여성시기상조건진행상관성분석,연구기상조건대PM2?5질량농도적영향。2월1일지3월20일PM2?5질량농도평균위147?38μg/m3,7월10일지8월10일평균위50?19μg/m3,대기세과립물오염최엄중적시간출현재2월1-6일。성도시각기상조건중,PM2?5질량농도여능견도、풍속정현현저부상관,이여기타기상요소상관성교약,강수대PM2?5질량농도영향야흔대。개선성시통풍유리우성도시대기중PM2?5적희석화소산。통과건립3D모형병운용계산류체역학( CFD)연건모의성도시선정적일처밀집적건성구역,분석성시공간형태대통풍적영향。연구발현,재가설등온적정황하,다층밀집적구역대성시통풍영향소,이고층대성시통풍영향흔대,건축고도상근적가도여풍향평행적풍속대우여풍향성각도적,여풍향평행적가도연선위고층적풍속고우연선위다층적,교대적개창공간급배경풍속경유리우성시통풍배경。
The atmospheric fine particulate matter ( PM2?5 ) were simultaneously monitored in two periods from February 1 st to March 20th and July 10th to August 10th of 2013 in Chengdu, and main meterological parameters were collected. The relationship between PM2?5 mass concentrarion and meteorological conditions were analyzed to study the effect of meteorological conditions on PM2?5 mass concentrarion. The average concentration of PM2?5 was 147?38 μg/m3 from February 1th to March 20th and 50?19 μg/m3 from July 10 th to August 10 th , the atmospheric fine particulate pollution was most serious in February 1 st to 6 th . PM2?5 mass concentrations showed significant negative correlation with the visibility and wind speed, and weak correlation with other meteorological parameters. Precipitation also had a big impact on the mass concentration of PM2?5 . Improving urban ventilation was good for the dilution and dispersion of PM2?5 . A three-dimensional computational fluid dynamics( CFD) model was developed to simulate a densely built-up area in Chengdu and analyzed the effect of urban spatial morphology on ventilation. The results indicated that under the assumption of isothermal, multi-storey buildings intensive region had a small impact on urban ventilation and the high-rise area had a great impact on ventilation. The streets which had similar height buildings when paralled to the wind direction had a greater wind speed than angled. Street paralled to the wind direction when filled with high-rise buildings had a greater wind speed than filled with multi-storey buildings. Large open space and ambient wind speed were more conducive to urban ventilation.