首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
室内颗粒运动和分布的模拟方法   总被引:4,自引:0,他引:4  
本文论述了模拟室内颗粒运动和分布规律的不同方法,包括集总参数模型、区域模型以及基于计算流体力学的模型。结合一些相关的实例,文中分别阐述了这些方法的特点、适合的应用对象和使用策略等。  相似文献   

2.
新风预处理概念、系统与应用   总被引:7,自引:0,他引:7  
李芃  沈晋明 《暖通空调》2002,32(6):104-107
美国《ASHRAE标准62-1999》要求增大空调系统的设计新风量,降低室内相对湿度以提高室内空气品质。这样,空调系统的冷、湿负荷将增大。据此,提出了新风预处理概念,它是在基本保持原有的传统空气处理系统不变的前提下,对新风进行合适的预处理,以消除增加的新风对空调对象的干预,从而经济有效地改善室内空气品质。最后,给出了几种新风预处理系统及应用。  相似文献   

3.
室内颗粒污染的源辨识与源解析   总被引:1,自引:0,他引:1  
辨识室内颗粒物来源与分析室内颗粒物元素特征称为源辨识与源解析,是进行室内空气污染控制与净化的理论依据与前提条件。本文通过对室内空气品质(IAQ)模型进行理论分析,阐明了室内外污染源与室内颗粒物浓度之间的关系。指出室内颗粒污染物研究应根据污染源已知与未知两种情况进行讨论,并针对不同的情况分别采用源辨识与源解析技术。  相似文献   

4.
随着对各种病态建筑综合症认识的逐步深入 ,国内的公众越来越注重室内空气品质( IAQ) ,迫切要求提高 IAQ.本文给出了几种新风预处理系统形式 ,可以经济有效的提高室内空气品质  相似文献   

5.
本文首先阐述了研究室内空气品质(IAQ)问题的重要性和必要性,介绍了目前已有的与室内空气品质相关的模拟软件。而后,基于"室内健康、环保和节能"的理念,提出了新的室内污染物浓度动态网络模拟分析与评估软件(DeST-IAQ)的理论框架,主要是将自然通风通路和机械通风网络集成,构成建筑通风和污染物传播的多区域网络模型,实现建筑通风和污染物浓度的联合动态预测,解决建筑通风模型、热模型和IAQ模型统一模拟的难题,满足建筑物能耗和室内空气品质预测的双重需求。该软件已在一些实际案例中得到了初步应用,其实用性具有较好的实验验证。  相似文献   

6.
A ventilation system usually runs on a certain schedule. The boundary conditions, such as the time-dependent outdoor particle concentrations and indoor particle generating sources, vary dynamically. Ventilated rooms are connected to ventilation ducts and filters, and indoor particle concentration and particle deposition on duct surfaces are interdependent. Thus it is important to study particle transport in the entire ventilation system and take the dynamic characteristics into account to assess particle pollution in the entire system more accurately. A generalized model is proposed in this study to estimate particle concentration throughout an entire ventilation system as well as mass loading of particles on ventilation components. Model equations describe particle movement in different ventilation components, including filters, ducts, and rooms. Penetration factors are adopted for filters and ducts, and particle concentrations in rooms are calculated by a lumped parameter method. This generalized model can be applied to any ventilation system, and a new software, PROBE-PM, was developed based on the presented model. Four case studies are carried out using this new software to demonstrate the application of the model.  相似文献   

7.
The purpose of this study was to examine the effects on humans of exposure to carbon dioxide (CO2) and bioeffluents. In three of the five exposures, the outdoor air supply rate was high enough to remove bioeffluents, resulting in a CO2 level of 500 ppm. Chemically pure CO2 was added to this reference condition to create exposure conditions with CO2 at 1000 or 3000 ppm. In two further conditions, the outdoor air supply rate was restricted so that the bioeffluent CO2 reached 1000 or 3000 ppm. The same 25 subjects were exposed for 255 min to each condition. Subjective ratings, physiological responses, and cognitive performance were measured. No statistically significant effects on perceived air quality, acute health symptoms, or cognitive performance were seen during exposures when CO2 was added. Exposures to bioeffluents with CO2 at 3000 ppm reduced perceived air quality; increased the intensity of reported headache, fatigue, sleepiness, and difficulty in thinking clearly; and reduced speed of addition, the response time in a redirection task, and the number of correct links made in the cue‐utilization test. This suggests that moderate concentrations of bioeffluents, but not pure CO2, will result in deleterious effects on occupants during typical indoor exposures.  相似文献   

8.
室内空气中潜在的化学反应与空气品质   总被引:2,自引:0,他引:2  
探讨了室内污染物发生潜在反应的环境条件 ,分析了臭氧与室内无机物和有机物可能发生的化学反应和光化学反应 ,讨论了这些潜在的反应对室内空气品质的影响 ,提出了改善室内空气品质的途径  相似文献   

9.
何维 《重庆建筑》2007,(10):49-51
文章分析了空调系统的污染对室内IAQ(Indoors Air Quality)的影响程度,指出随着其它污染源被控制,其影响将更加突出;分析了空调系统各部件污染的成因,以及这些污染对IAQ的影响。根据国内外相关文献,结合空调系统设计运行情况和工作实践,提出防止空调系统污染的措施。  相似文献   

10.
There is worldwide plea to reduce carbon dioxide emission. In response to such a call, several governments in East Asia recently have required to adopt higher room temperatures in summer. To promote such an idea, the public need to be convinced that such practice would not sacrifice indoor environmental quality, especially thermal comfort of the occupants. To implement such a measure, suitable ventilation system(s) to work under the unconventional conditions should be identified.  相似文献   

11.
室内化学污染物的评价新方法   总被引:6,自引:1,他引:6  
刘玉峰  沈晋明 《建筑科学》2002,18(6):53-55,52
论述了化学污染物是导致室内空气品质问题的主要原因,提出CO2和HCHO可以作为评价室内化学污染水平的代表,并建立了各自的对数评价指标的定义式,验证了对数评价指标与不满意率之间存在很好的线性相关关系,定义了反映室内化学污染水平的综合评价指数,给出了综合指数的计算方法,并按综合评价指数对室内污染水平进行了分类。  相似文献   

12.
Indoor air quality (IAQ) on ships is important for the passengers’ comfort and the crew’s work efficiency, despite ships not being as common as vehicles and airplanes. The builders and operators need to be aware of the importance and present status of IAQ, but sufficient data and information are not available. In this study, we measured the pollutant concentrations on two different kinds of newly launched ships: a passenger ship and a chemical cargo ship. Although higher than in the passenger ship, the concentrations of most volatile organic compounds (VOCs) and formaldehyde in the cargo ship were lower than the recommended standards and acceptable with a few exceptions. The high CO and CO2 concentrations in the kitchen, engine room, and engine control room were generally attributed to combustion sources. Overall, the IAQ of the cargo ship was worse than that of the passenger ship, and the concentrations of some pollutants surpassed the international criteria. For the passenger ship, the variation of IAQ was also investigated after 17 months. The observed data showed some differences in concentration variation according to the types of pollutants. To improve IAQ on ships, more data need to be collected and minimum requirements suggested.  相似文献   

13.
影响室内空气品质的VOC特性及其定量评估   总被引:11,自引:0,他引:11  
忻尚杰  程宝义  朱培根 《暖通空调》2002,32(3):34-35,59
介绍了用于挥发性有机化合物评估的空气耗氧量(COD)指标,阐述了COD与室内空气品质其他指挥的显著相关性,指出空气耗氧量是综合性很强的空气污染指标。指出了改善室内空气品质的技术和措施。  相似文献   

14.
Natural materials of biological origin degrade over time and may emit odorous chemical compounds that can influence the perceived indoor air quality. The objective of this study was to investigate how the perceived air quality is influenced by emissions from building products with linseed oil compared with similar conventional synthetic products without linseed oil. Two types of linoleum, two types of wall paint and two types of floor oil were selected as examples of natural products containing linseed oil. The selected synthetic products were PVC floor covering, a water-based paint, and a synthetic floor oil. The emissions from the products were monitored over a one-year period in small ventilated test chambers. The odorous emissions were evaluated by sensory panel assessments of odour intensity and acceptability and by chemical analysis of the odour-active volatile organic compounds (VOCs) and carbonyl compounds. Odour-active VOCs in the emissions from one floor oil with linseed oil and two pure linseed oils were detected by gas chromatography combined with olfactometry (GC-O) and attempted identified with mass spectrometry (MS). The products with linseed oil influenced the perceived air quality more negatively than the similar synthetic products and the odour was persistent over time. It was found that the products with linseed oil did not qualify for the Danish Indoor Climate Label, because of the persistency of the odour. The results of the GC-O/MS investigations and VOC measurements indicated that an almost constant emission of odour-active VOCs with low odour thresholds resulted in the persistency of the odour. The VOCs probably originated from oxidation products from the linseed oil used as raw material. The study indicates that the acceptability of the emissions from the floor oil was influenced by the linseed oil used as raw material. It is therefore suggested that systematic use of less odorous linseed oils may improve the acceptability of the emission from products with linseed oils. The applied combination of sensory assessment of perceived air quality and GC-O/MS seems to be a useful approach in the effort to eliminate unwanted odours from building products.  相似文献   

15.
Many studies have shown that the use of laser printing devices (LPDs) contributes to the release of particles into the indoor environment. However, after more than two decades of research, the physicochemical properties of LPD-emitted particles and the possible health effects from exposure to particles are still heavily debated. We therefore carried out a critical review of the published studies around emissions and health effects of LPD-emitted particles, aiming at elucidating the nature of these particles and their potential health risks. Realizing the varying methodologies of the studies, a classification of the reviewed studies is adopted, resulting in three categories of emission studies (chamber experiment, office/room measurement, and photocopy shop measurement), and three types of health studies (in vitro/animal studies, human studies in the real world, and human studies in controlled settings). The strengths and limitations of each type of study are discussed in-depth, which in turn helps to understand the cause of divergent results. Overall, LPD-emitted particles are mainly condensed or secondary-formed semi-volatile organic compounds (SVOCs), while solid toner particles account for a very small fraction. The health risk from exposure to LPD-emitted particles is small compared with the health risk from exposure to ambient particles.  相似文献   

16.
This paper presents a case to investigate the effect of partitions in an office on the performance of under floor air supply ventilation system via computational fluid dynamics. The assessment is in terms of thermal comfort and indoor air quality with the use of a validated computer model. The results indicate that the partitions may significantly affect airflow and performance of a under floor air supply ventilation system. In particular, the presence of a gap above the partition wall is able to improve air distribution owing to less air re-circulation in the upper zone. Its effect on thermal comfort and indoor air quality indicators are evaluated.  相似文献   

17.
The purpose of this paper is to investigate, using a validated computational fluid dynamics simulation, the effect of the position of doors on performance of the displacement ventilation system. The results are reported in terms of thermal comfort and indoor air quality. The study focuses on a typical Hong Kong office under local thermal and boundary conditions. It was found that the presence of large heat sources such as from a window can cause the lateral movement of airflow, disrupting the convection effect which the displacement ventilation system relies on. Doors can create this situation when they are opened by changing the thermal boundary conditions of indoor spaces. The designer should be made aware of this possibility and make appropriate design decisions to accommodate for this fact.  相似文献   

18.
The aim of this study was to evaluate the air quality of an indoor swimming pool, analyzing diurnal and seasonal variations in microbiological counts and chemical parameters. The results indicated that yeast and bacteria counts, as well as carbon dioxide (CO2), nitrogen oxides (NOx) and O3 concentrations, showed significant diurnal difference. On the other hand, temperature, relative humidity (R.H.), yeast counts and concentrations of CO2, particles, O3, toluene, and benzene showed seasonal differences. In addition, the relationship between indoor and outdoor air and the degree of correlation between the different parameters have been calculated, suggesting that CO2, fine particles and NOx would have indoor origin due to the human activity and secondary reactions favored by the chemical and environmental conditions of the swimming pool; while O3, benzene and toluene, would come from outside, mainly. The overall results indicated that indoor air quality (IAQ) in the swimming pool building was deficient by the high levels of CO2 and microorganisms, low temperatures, and high R.H., because frequently the limits established by the legislation were exceeded. This fact could be due to the poor ventilation and the inadequate operation of heating, ventilation, and air‐conditioning systems.  相似文献   

19.
置换通风在办公建筑中的应用与分析   总被引:4,自引:2,他引:2  
利用计算流体力学(CFD)方法,对使用置换通风的办公建筑进行计算机数值模拟对室内空气的速度场、温度场进行分析,认为置换通风在提高空内空气品质和节能方面具有一定的效果。  相似文献   

20.
A number of past studies have shown the prevalence of a considerable amount of volatile organic compounds (VOCs) in workplace, home and outdoor microenvironments. The quantification of an individual's personal exposure to VOCs in each of these microenvironments is an essential task to recognize the health risks. In this paper, such a study of source apportionment of the human exposure to VOCs in homes, offices, and outdoors has been presented. Air samples, analysed for 25 organic compounds and sampled during one week in homes, offices, outdoors and close to persons, at seven locations in the city of Leipzig, have been utilized to recognize the concentration pattern of VOCs using the chemical mass balance (CMB) receptor model. In result, the largest contribution of VOCs to the personal exposure is from homes in the range of 42 to 73%, followed by outdoors, 18 to 34%, and the offices, 2 to 38% with the corresponding concentration ranges of 35 to 80 microg m(- 3), 10 to 45 microg m(- 3) and 1 to 30 microg m(- 3) respectively. The species such as benzene, dodecane, decane, methyl-cyclopentane, triethyltoluene and trichloroethylene dominate outdoors; methyl-cyclohexane, triethyltoluene, nonane, octane, tetraethyltoluene, undecane are highest in the offices; while, from the terpenoid group like 3-carane, limonene, a-pinene, b-pinene and the aromatics toluene and styrene most influence the homes. A genetic algorithm (GA) model has also been applied to carry out the source apportionment. Its results are comparable with that of CMB.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号