街道峡谷内污染物扩散对周边建筑物自然通风影响的研究进展

介绍了城市街道峡谷内污染物的特点和扩散模式,分析了换气效率、室内气流组织、污染物扩散方式等影响建筑自然通风的主要因素,并对实地测量法和数值模拟法进行了分析和比较。     

街谷几何形态及绿化对夏季热环境的影响

本文利用基于CTTC模型的DUTE软件,以湿热地区广州的城市街谷为例,对城市街谷内的湿球黑球温度(WBGT)和热岛强度进行了模拟计算.通过对比分析,比较了不同高宽比、走向、对称性、绿化等设计因素对街谷内日间平均WBGT和热岛强度的影响.研究结果表明:窄街谷较之宽街谷、南北走向街谷较之东西走向街谷有着更好的热环境;街谷乔木率与热岛强度的降低呈线性正相关;对称与否对街谷内热环境的影响较小.本文初步探索了街谷几何形态及绿化对街谷热环境的定量影响,为城市规划和街谷设计提供了有针对性的参考指引,以期促进街谷热环境的设计,营造安全、舒适的街谷热环境.     

背景风速对上游有阻挡建筑的街谷环境的影响

通过数值模拟针对街谷上游存在阻挡建筑时,研究了不同背景风速下,街谷内速度场和污染物浓度场的变化特征。结果表明,街谷内风速和湍流强度的增加幅度小于背景风速的增大幅度,但背景风速的变化对街谷内的气流流态和分布规律几乎没有影响。在风速和湍流强度的双重影响下,污染物浓度的减小幅度大于风速增加的幅度。因此对于目前的城市街谷来说,可以根据风速的不同对城市交通管理做出相应的调整。     

街区空间形态对于交通污染在街谷相邻街区扩散的影响研究

街区空间是居民活动最活跃的场所,由街谷空间内部交通污染扩散引起的街区空间空气质量的变化是受到广泛关注的问题。研究利用CFD模拟的方法,针对街谷内交通污染物随气流向街谷相邻空间的扩散状况进行模拟分析。通过对18个案例从建筑山墙间距、街谷高宽比及建筑错列式布局三个方面探讨街区空间形态的差异对交通污染在街谷相邻空间内的浓度变化与分布特征的影响。研究结果表明建筑山墙间距、街谷高宽比及建筑错列式布局的差异对街区风环境产生明显影响,从而影响交通污染物在街谷及相邻空间内的扩散,导致街谷上下风向的相邻街区内交通污染浓度有不同程度的升高趋势。     

高架覆盖采风口型街谷内PM2.5分布模拟

本文对有高架覆盖和无高架覆盖下30 m采风口型街谷内PM2.5的分布进行了三维数值模拟。提出一种新的评价方法,分析了高架路的存在对街谷内颗粒物浓度分布的影响。结果表明:高架路的存在会增大颗粒物的浓度,阻碍颗粒物向街谷外部扩散,颗粒物浓度增加率为20%左右。     

绿色居住建筑室内空气质量检测与控制策略探讨

室内空气质量是影响绿色居住建筑舒适性的主要因素之一。因此,对绿色居住建筑中的室内空气污染物进行检测是十分有必要的。从理论上分析了绿色居住建筑室内空气污染物质的主要来源、检测方法,探讨了优化室内空气质量的策略。     

城市街谷中的物理微环境

根据大气湍流观测和相关的大气气溶胶研究结果，分析了城市街谷内微环境的主要特征．兼顾城市规划和改善街谷环境的要求，对街谷微环境的改善提出了某些便于实施的基本途径．     

水平遮阳构件对单侧通风及污染物浓度分布的影响研究

自然通风是改善室内空气质量的有效方法.本文以水平遮阳构件为研究对象,在三种不同高宽比的街谷形态下,研究了5种水平遮阳构件的宽度对临街建筑的单侧自然通风及室外交通污染扩散的影响.笔者通过开源CFD软件OpenFOAM,建立了流场和污染物扩散的三维数值模型.模拟结果表明,水平遮阳构件的宽度与室内换气率的变化率有非常强的相关...     

基于交通能耗的城市空间和交通模式宏观分析及对我国城市发展的启示

应用主成分分析和聚类分析方法对北美、大洋洲、西欧、亚洲、东欧、中东、非洲和拉丁美洲的87个城市的能源消耗和城市空间、交通模式数据进行了分析,寻找影响影响私家车和公共交通能源消耗的主要因素.主成分分析显示,私家车交通和公共交通能耗影响因素不同,而城市密度并不是影响交通能源消耗权重最大的因素.聚类分析显示,全球主要城市能源消耗模式可分为3大类6亚类,城市交通能源消耗情况与城市的空间、交通模式和经济水平有着密切联系.研究结论认为,对我国城市发展而言转换交通模式是减少城市能源消耗的主要途径,同时非机动交通模式的发展对能源消耗的降低起着重要的作用,最后提出了对我国建设低能耗城市的启示.     

住宅室内细菌污梁现状与分析

针对影响住宅室内空气品质的空气中细菌浓度水平进行测试、分析、研究。通过对住宅室内空气中的微生物浓度进行测定, 并对造成室内空气中细菌污染的原因进行分析,指出在重庆住宅室内空气中存在着严重的细菌污染问题,其主要影响因素是空气的湿度和自然通风、采光情况;建筑结构形式、室内布置和地面装饰材料也是较重要的影响因素。提出提高室内空气品质,改善室内环境质量,防止室内空气中细菌污染的措施、建议     

Indoor air environment of residential buildings in Dalian,China

In recent years, more and more people have started to recognize the importance of indoor air environment. In order to obtain the comprehensive knowledge about the indoor environment situation and find out the main source of indoor air pollution, 550 residents living in different buildings/apartments were subjected to a questionnaire survey and field measurements were conducted in 30 of these buildings/apartments in Dalian from January to February 2002. From the questionnaire survey and field measurements, we found that many residential buildings had good outdoor surroundings. Dust and automobile emissions are main sources of outdoor air pollution. Though air tightness of these buildings is fairly good, outdoor air quality still has great impact on indoor air environment. The most serious indoor air pollutant is formaldehyde which is mainly caused by decoration.     

室内空气污染及防治措施

室内空气品质优劣对人体健康影响很大,并会导致人们工作效率降低,建筑物的密闭性和室内装修热的影响加剧了室内环境污染,所以对室内空气污染进行分析和找出防治措施是一件非常有意义的事。本文分析了室内空气污染的主要来源,通过对国内外室内空气污染的现状分析,意识到治理空气污染的必要性和紧迫性。同时找出我国室内环境污染的原因和问题所在,提出了我国室内空气污染防治的有效措施,以改善室内空气品质。     

Real‐Time Estimation of Pollution Emissions and Dispersion from Highway Traffic

Traffic‐related air pollution is a serious problem with significant health impacts in both urban and suburban environments. Despite an increased realization of the negative impacts of air pollution, assessing individuals' exposure to traffic‐related air pollution remains a challenge. Obtaining high‐resolution estimates are difficult due to the spatial and temporal variability of emissions, the dependence on local atmospheric conditions, and the lack of monitoring infrastructure. This presents a significant hurdle to identifying pollution concentration hot spots and understanding the emission sources responsible for these hot spots, which in turn makes it difficult to reduce the uncertainty of health risk estimates for communities and to develop policies that mitigate these risks. We present a novel air pollution estimation method that models the highway traffic state, highway traffic‐induced air pollution emissions, and pollution dispersion, and describe a prototype implementation for the San Francisco Bay Area. Our model is based on the availability of real‐time traffic estimates on highways, which we obtain using a traffic dynamics model and an estimation algorithm that augments real‐time data from both fixed sensors and probe vehicles. These traffic estimates combined with local weather conditions are used as inputs to an emission model that estimates pollutant levels for multiple gases and particulates in real‐time. Finally, a dispersion model is used to assess the spread of these pollutants away from the highway source. Maps generated using the output of the dispersion model allow users to easily analyze the evolution of individual pollutants over time, and provides transportation engineers and public health officials with valuable information that can be used to minimize health risks.     

Location of air intakes to avoid contamination of indoor air: a wind tunnel investigation

The location of air intakes is of prime importance in buildings that are situated in close proximity to busy urban roads. If intakes are placed where the concentration of traffic pollution is high then indoor air concentrations can reach similarly high levels. This paper presents the findings from a wind tunnel investigation into the dispersion of a simulated traffic pollutant in a 1:100 scale model. The concentrations at different points on a building in the model are measured and a comparison with full-scale data is made.     

室内外空气中CO浓度的变化规律

以CO为示踪气体，通过对上海市某些街道的环境空气受机动车废气污染的程度和有关影响因素进行的监测和分析，给出院 街道中交通废气中CO的浓度分布特征和室内外浓度变化的量化关系，并讨论了待区CO浓度的变化对自然通风房间和空调系统的作用。     

Inverse identification of multiple outdoor pollutant sources with a mobile sensor

Air pollution is becoming more and more severe in large cities. Accurate and rapid identification of outdoor pollutant sources can facilitate proper and effective air quality management in urban environments. Traditional “trial–error” process is time consuming and is incapacity in distinguishing multiple potential sources, which is common in urban pollution. Inverse prediction methods such as probability based adjoint modelling method have shown viability for locating indoor contaminant sources. This paper advances the adjoint probability method to track outdoor pollutant sources of constant release. The study develops an inverse modelling algorithm that can promptly locate multiple outdoor pollutant sources with limited pollution information detected by a movable sensor. Two numerical field experiments are conducted to illustrate and verify the predictions: one in an open space and the other in an urban environment. The developed algorithm promptly and accurately identifies the source locations in both cases. The requirement of an accurate urban building model is the primary prerequisite of the developed algorithm for urban application.     

空调系统新风供给形式对室内颗粒污染物的影响

着重探讨了风机盘管加新风的空调系统和两种变风量空调系统形式中,新风量,新风过滤效率和室外含尘粒子对室内颗粒污染物的影响,最后指出对一次,二次风的混合进行中效过滤的全空气系统,能够明显提高新风稀释和排除室内粉尘的能力,完全能够满足是用户对环境日益增加的健康和舒适方面的要求。     

Building calibration for IAQ management

Demand Control System (DCV) is designed to optimise the energy consumption with respect to the demand of outdoor air quantity based on the number of people indoors. However, if significant indoor pollutant sources exist, which is not a function of the number of people, the DCV may cause the indoor air quality to be unacceptable. This paper discusses a procedure of calibrating the building in respect of managing the indoor air quality. The objective is to set the minimum fresh air quantity which is a function of the indoor pollutant concentrations rather than metabolic carbon dioxide. Radon is used as an example because it is a common pollutant embedded in the building materials of high-rise buildings in Hong Kong. This paper also presents a year-round record of the indoor air quality in a typical high-rise building which is very useful for building indoor air quality (IAQ) design.