上海村镇居住建筑夏季风扇用能模式研究

本文通过CFD模拟,研究风扇对上海村镇居住建筑室内热环境的改善效果与节能潜力、居民对夏季自然通风与风扇结合的接受度及适用范围。研究结果表明:夏季利用风扇可以提高上海村镇居住建筑室内风速、降低室内温升并改善室内热场分布,结合自然通风可在一定程度上代替空调进行降温。当室外温度超过29.8℃时,风扇和自然通风将无法保证室内人员舒适度,建议开启空调进行降温;风扇在空调开闭情况下较单用空调制冷可分别节能13.5%~14.5%和93%~94%。     

自然通风与分层空调耦合运行的节能分析

自然通风及分层空调在大空间建筑中均有单独使用,而将两者结合使用的研究较少.本文应用FLUENT软件,对采用自然通风耦合分层空调方式下的室内热环境进行了数值模拟,并与单独采用分层空调方式进行比较.结果表明,采用耦合送风可以显著改善室内热环境,降低室内空调能耗,是大空间建筑节能的发展方向,值得深入研究.     

农村住宅夏季自然通风设计研究

利用室内自然通风系统来通风降温,取代过去单纯依靠空调送风的局面,是近年来室内通风的发展方向,自然通风能够为室内提供充足的新鲜空气,并且在夏季起到降低室内温度的作用,减少空调的使用。该文以扎兰屯某农村住宅为例,展示了通过数值模拟改进建筑方案的过程,提出了数值模拟指导设计的新方法。     

室内环境与自然通风

通风的目的是保证室内良好的空气品质,采用自然通风方式是生态建筑设计的重要内容,通过良好的自然通风组织减少对空调的利用,并及时将污染物排出,改善室内空气品质。在热舒适方面,自然通风形成的室内热环境有利于人体舒适性。分析了生态建筑中自然通风对室内空气品质与室内热环境产生的影响,探讨了利用自然通风来改善建筑的室内环境的效果和策略,并提出了相应的设计方法。研究结果表明:组织合理的自然通风,可以有效地改善室内的空气品质和室内热环境。     

新广州火车站自然通风潜力分析

运用多区域网络模拟工具ContamW对新广州火车站进行了自然通风设计优化。优化结果为:当室外温度低于21℃时,只需自然通风即可满足室内通风换气和热舒适要求;当室外温度为21~28℃时,可自然通风区域首先利用自然通风,当室温不能保证时再开启空调降温,其他区域运行空调系统降温;当室外温度高于28℃时,全部空调系统运行,建筑门窗处于关闭状态。     

以西安地区为例谈自然通风在教学建筑中的应用

自然通风作为传统的被动式降温方式,不但可以有效的改善室内的热环境,而且能够降低对空调系统的依赖,从而节约空调能耗.文章以西安地区为例,结合当地的气候特点及高校教室的具体情况,从总体规划和单体设计两方面论述了自然通风在教学建筑中的应用.提出了加强室内通风的建议.     

厦门住宅夏季空调运行实测及其相关分析

本文采用实测方法对厦门4户住宅夏季空调室温变化进行记录,统计分析了空调启用室温、空调同时使用及室内人员作息情况。结果表明:厦门住户拥有空调数2~3台,以3台为多;拥有活动电扇1台;空调器都安装在客厅和卧室,一般是在室内气温高于28℃后才启用,室内气温低于28℃时,可以利用自然通风实现室内热舒适,室内气温在28℃~30℃时,自然通风可使室内热环境达到可接受水平;客厅空调一般在白天和晚间使用,主卧室和次卧室空调一般用于白天午休和夜间休息,客厅、主卧、次卧空调都存在同时使用情况,进行空调能耗模拟时,考虑空调同时使用系数,客厅4人,主卧2人,次卧1人是合适的。     

医院建筑室内自然通风模拟优化研究

应用PHOENICS模拟仿真技术对医院门诊楼现状室内自然通风以及改进后的室内自然通风进行数值模拟研究。结果表明改进后的方案室内风速、换气次数显著提高,温度和空气龄显著下降,室内环境舒适性明显改善。该研究为医院建筑优化自然通风,降低过渡季节的空调制冷能耗提供可供借鉴的实例。     

农业种植对室内环境影响研究初探

实验选取办公楼南向的相邻隔间,采取空白对照的方式,选取其中一个隔间的室内窗台种植水果型黄瓜,形成“黄瓜窗帘”。测量、比较两个隔间的光照强度、温度和空气相对湿度。对照测量实验开展时间为7月14日～7月24日,采取自然通风和使用空调降温两种方式。实验结果验证室内农业种植在自然通风和使用空调降温条件下,降低室内光照强度、消除室内眩光,并通过减少室内太阳辐射、降低室内温度,在使用空调时提高室内空气相对湿度,并具有一定农业收益。     

高校图书馆建筑中通风技术应用研究

为了研究日间自然通风和夜间机械通风对室内热环境的影响,选取湖南省某高校图书馆为研究对象。用Energyplus进行了模拟分析,先研究了日间自然通风时室内逐时温度和无效时数,然后研究了日间自然通风和夜间机械通风耦合作用时室内逐时温度和无效时数。结果发现,日间自然通风模式下,4月,5月,6月,9月和10月的无效时数分别为64 h,138 h,333 h,290 h和99 h,增加5次/h的夜间机械通风后,4月和10月室内热环境可满足使用要求,5月,6月和9月可减少空调的使用时间,空调开启时间可分别设置为14:00-19:00,10:00-20:00和13:00-20:00。     

Mathematical modeling and experimental study on vertical temperature distribution of hybrid ventilation in an atrium building

An extended Gebhart-Block model for large space buildings is proposed in this paper, which is used to predict the vertical temperature distribution of hybrid ventilation. Natural ventilation coupled with air-conditioning is described with a mathematical model. The indoor thermal environment formed by the air-conditioning and the natural ventilation can also be conducted for the potential analysis and optimal use of the natural ventilation. Experiments were carried out in an atrium building in Shanghai Research Institute of Building Sciences. This paper describes aforementioned model, and it is found that the calculation results implying this model agree well with the measurement data.     

Effects of outdoor air conditions on hybrid air conditioning based on task/ambient strategy with natural and mechanical ventilation in office buildings

This research aims to clarify the effects and indoor environmental characteristics of natural and mechanical hybrid air-conditioning systems in office buildings during intermediate seasons and to obtain design data. Natural and mechanical hybrid air conditioning is an air-conditioning system that utilizes natural ventilation and mechanical air-conditioning systems to improve the quality of the indoor thermal and air environment, and to reduce energy consumption. This report first categorizes the available natural ventilation conditions and estimates the amount of natural ventilation available in a model building. Furthermore, based on the concept of task-ambient air conditioning, after controlling the average temperature in the task zone to a target air conditioning temperature (26°C), changes in the outdoor temperature/humidity and the inflow rate, and the indoor environment and amount of cool heat input were studied with changes in the size of the natural vent using three-dimensional Computational Fluid Dynamics (CFD) analysis. The results of these studies indicated that natural ventilation at temperatures lower than the indoor temperature effectively covered the lower indoor task zone through negative buoyancy, which enabled energy-saving air conditioning in the task zone.     

自然通风建筑能耗全年模拟研究

自然通风是降低建筑能耗的重要手段.现有的软件工具难以准确计算自然通风条件下的全年建筑能耗,限制了自然通风在建筑节能设计中的应用.本文从自然通风计算及耦合计箅两方面进行改进,提出了一套可靠、准确的自然通风与热环境耦合计算的模拟方法和对应的评价指标.而后,以建筑能耗模拟软件DeST为平台,开发出了自然通风风量及建筑能耗的全年逐时模拟软件DeST-Vent+.利用DeST-Vent+软件对北京地区3种自然通风类型下办公建筑的全年空调冷负荷进行了模拟计算,分析了不同通风形式的节能潜力.     

Building energy efficiency and thermal comfort in tropical climates: Presentation of a numerical approach for predicting the percentage of well-ventilated living spaces in buildings using natural ventilation

The paper deals with the optimization of building energy efficiency in tropical climates by reducing the period of air-conditioning thanks to natural ventilation and a better bioclimatic design. A bioclimatic approach to designing comfortable buildings in hot and humid tropical regions requires, firstly, some preliminary, important work on the building envelope to limit the energy contributions, and secondly, an airflow optimization based on the analysis of natural ventilation airflow networks. For the first step, tools such as nodal or zonal models have been largely implemented in building energy codes to evaluate energy transport between indoor and outdoor. For the second step, the assessment of air velocities, in three dimensions and in a large space, can only be performed through the use of detailed models such as with CFD. A new modelling approach based on the derivation of a new quantity—i.e. the well-ventilated percentage of a living space is proposed. The well-ventilated percentage of a space allows a time analysis of the air motion behaviour of the building in its environment. These percentages can be over a period such as 1 day, a season or a year. Twelve living spaces with different configuration of openings have been studied to compare the performance of ventilation function of the opening distribution. Results and discussion are presented in the paper. This method is helpful for an architect to design the rooms according to their use, and their environment. Finally, the developed models can be used in building projects to estimate the period of the natural ventilation and to reduce the energy consumption due to air-conditioning.     

夏热冬暖地区住宅建筑节能措施

夏热冬暖地区夏季能耗较高，其建筑节能的重点是降低夏季的空调能耗。自然通风可以为居住建筑改善空气品质，并最大限度的减少空调使用时间，改善室内热环境；而建筑外遮阳技术也可以有效降低空调能耗，同样可以减少空调使用时间。在夏热冬暖地区自然通风和建筑外遮阳技术是建筑节能的关键技术和重要组成部分。     

河南地区办公建筑自然通风策略

自然通风是改善办公空间空气品质,降低空调制冷能耗最有效的方式之一,本文通过分析办公建筑的几种空间布局形式,归纳总结出不利于实现自然通风的因素,研究得出应对方法。     

置换通风辐射空调不同结合方式的模拟比较

置换通风和辐射空调这两种空调方式的结合是目前运用较少的空调末端方式,置换通风主要是解决空调房间新风供给和承担房间的湿负荷.模拟研究设计条件下置换通风天棚辐射供冷与置换通风地板辐射供冷时房间的温度、湿度和速度分布,从而优化设计、避免结露.模拟结果表明在同样的设计条件下,置换通风天棚辐射供冷具有较好的的温度分布、湿度分布和速度分布.     

不同城市自然通风建筑热舒适状况研究

通过上海、长沙自然通风建筑内进行的人体热舒适调查研究，并结合有关文献中北京和天津热舒适研究的成果，对我国目前不同城市自然通风建筑内热舒适状况进行探讨。结果认为，我国自然通风建筑内热中性温度均略高于ASHRAE推荐范围，采用实测的舒适温度作为空调温度可节约大量的能量。     

绵阳地区不同自然通风策略对公共建筑基础室温及能耗的影响

本文详细介绍了自然通风研究的现状,并以绵阳某公共建筑为研究对象,以绵阳地区夏季和过渡季为气候限定条件,运用DeST能耗模拟软件分析了不同自然通风策略对室内基础室温及空调冷负荷的影响,得出该特征气候区在4～10月宜采用夜间通风.该研究结果可为与绵阳气候相近地区的建筑设计及建筑节能改造提供参考.     

Enhancement of ventilation performance of a residential split-system air-conditioning unit

The design of ventilation performance of air-conditioning systems in large commercial and office buildings is quite established. However, it is not the same with the designs of air-conditioning systems in most residential buildings. Split system air-conditioning units are commonly employed in residential buildings in the tropics due to their convenience in terms of energy conservation, aesthetics, flexibility, acoustic performance and ease of operation. Such units are also popular among small offices, shopping complex and even as supplementary air-conditioning units beyond normal office-hours in large commercial and office buildings. This paper presents findings from a recent study of the ventilation performance and indoor air quality (IAQ) in a master bed room of a condominium unit in Singapore, employed with a split system air-conditioning unit. The attached bathroom is equipped with an exhaust fan, whose operation and its impact on the resulting ventilation characteristics was also studied. Four adults occupied the room throughout the course of the experiments. It was observed that the carbon dioxide level in the bed room can exceed 2000 ppm without the exhaust fan in about 2 h. The operation of the exhaust fan quickly lowered the level of carbon dioxide to about 1000 ppm. The findings suggest the need to design for ventilation provision in split system air-conditioning units.