被动式蒸发冷却下向通风降温技术在中庭中应用的思考

被动式直接蒸发冷却下向通风降温技术是一种高效、无污染、低能耗、使用费用低廉的绿色降温技术,被认为是中庭降温的最佳技术,该文用案例分析的方法比较了以色列布劳斯坦沙漠建筑研究中心和美国凤凰城奥康纳联邦法院的中庭设计方法及其技术措施,揭示了利用相同技术为中庭降温而产生截然不同热舒适效果的原因,提出被动式建筑设计原则、适宜的技...     

被动式建筑通风降温策略

从空调降温存在的问题切入,引出被动式建筑通风降温的主题,提出加强型被动式通风降温和预冷型被动式通风降温的原理。其中加强型通风包括风压通风和热压通风,预冷型通风包括蓄冷腔体通风、地下腔体通风和蒸发降温通风,并根据其实现形式,提出相应的建筑设计策略。论证了降温原理与降温效果,为被动式降温设计提供一些新思路与新方法。     

居住建筑被动降温节能效应分析

选择适宜的被动式降温设计方法可以有效降低空调能耗,通过选取我国各气候区的典型城市住宅建筑作为研究对象,对于常用被动式降温方法,如遮阳、夜间通风及蒸发冷却,采用了软件模拟及数值计算的方法分析了其节能效应,旨在对不同气候区的建筑设计提供技术参考。     

风塔型蒸发冷却通风降温系统研究

介绍了被动式蒸发冷却风塔、太阳能烟囱的基本原理。通过对被动式蒸发冷却风塔试验模型的测试及分析,发现其存在风量相对较小且不可控的不足。结合"一带一路"沿线地区丰富的干燥空气可再生能源及太阳能资源,提出了太阳能烟囱与风塔型蒸发冷却降温系统相结合的复合系统。对该系统进行了初步设计,理论分析表明:这2种技术的结合具有实际意义。提出了该系统的测试方案并进行测试。     

能源自给型太阳能建筑设计实录

介绍一座以广州市气候为背景的能源自给型太阳能建筑的设计过程。针对太阳能一体化设计、适度应用太阳能光伏发电板以及此类太阳能建筑的平面布局等问题,以气候分析结论为依据,被动式设计优先为原则,采用温度梯度布局方法,运用被动式蒸发降温、自然通风等对策进行设计,并结合发电量模拟数据来论证该建筑的可行性。以期所述建筑设计要点对相似气候区下的太阳能建筑设计具有借鉴意义。     

基于室内热环境的高寒地区被动式设计策略

实地调研甘孜州康定民居室内热环境发现,在当地严寒气候条件下,由于民居被动式设计的缺失,围护结构热工性能差,室内热环境极不理想。结合甘孜地区气候条件,利用weathertool分析当地气象数据,基于焓湿图明确适应当地的被动式设计策略范围,并定量分析各设计策略在每月的有效时间比。结果显示,被动式太阳能和建筑蓄热年综合有效时间比分别达到了21.3%、20.8%,为最适宜于当地的被动式设计策略。在此基础上提出当地民居设计被动式设计要点,以期为当地的民居设计提供指导。     

被动式蒸发冷却下向通风降温技术的研究与应用

介绍被动式蒸发冷却下向通风降温技术的原理、优势、及其在当代的研究和应用,并通过对吐鲁番地区的气候分析,展望该技术在我国西北等干热地区应用的可行性。     

被动式设计策略的适用性研究

利用气候分析软件Ecotect分析、统计了全国200个城市的气候分析结果.利用相关统计软件进行了验证分析.在此基础上利用地理信息系统GIS(ARCGIS9.2)软件的插值功能,在Kriging插值的基础上形成了被动式设计的潜力、被动式策略的综合贡献、被动式太阳能利用、直接蒸发冷却、建筑蓄热性能+夜间通风,自然通风的适用性分区图.     

被动蒸发冷却屋面在夏热冬冷地区的应用

被动蒸发冷却屋面作为一项节能技术,在夏热冬冷地区的应用目前并不广泛。在国家大力提倡节能降耗的背景下,被动蒸发冷却技术作为一项"被动式"技术可以有效地与"主动式"技术结合起来,最终达到一个节能舒适的室内居住环境。查阅相关研究成果,主要介绍了遮挡式蓄水屋面和含湿多孔材料屋面两种常见被动蒸发冷却屋面。利用CFD软件对其进行模拟,并与普通刚性屋面进行对比,从不同的角度对被动蒸发冷却屋面技术进行简要的分析。研究了被动蒸发冷却屋面的降温幅度以及建筑体型系数对其影响,分析了被动蒸发冷却屋面的热舒适性。     

海洋性气候条件下新型特隆布墙被动降温的通风模式研究

针对被动式太阳房普遍存在的夏季室内过热问题，对海洋性气候条件下带有新型特隆布墙的被动式太阳房进行了实验研究，分析了不同被动降温模式的降温效果和室内空气温度分布。给出了适用于该类太阳房被动降温的最佳通风模式。认为内壁面温度是室内气温最显著的影响因素。与内陆地区利用自然通风降温的效果进行了对比。分析表明提高通风量、强化夜间通风可以改善海洋性气候条件下被动降温的效果。     

各气候区被动建筑节能技术适用性分析

被动式建筑节能,是通过利用自然气候资源的生态建筑设计原理,赋予建筑本身节能自然特性而实现的建筑节能,因而更为绿色环保,更有利于人类生存环境的可持续发展,成为建筑节能积极倡导的方向。针对中国各气候区典型城市的气候特点进行被动式太阳采暖、自然通风、蓄热墙体、诱导+夜间通风、直接蒸发冷却和间接蒸发冷度这六种被动式建筑节能技术适用性进行分析,并对各气候区的各种被动式建筑节能技术的适用性进行对比。     

Solar thermal modelling of a building with a roof pond and ventilation control systems

The paper proposes and presents thermal modelling of a ventilation-controlled, non-air-conditioned building with evaporative cooling (e.g. open water pond) over the roof for passive solar air conditioning. The ventilation rate, expressed in terms of number of air changes per hour, is assumed to be time-dependent, as should be the case in normal practice. A self-consistent periodic heat transfer analysis for a non-air-conditioned building with roof cooling and ventilation control systems, furnishing (assumed isothermal mass), windows, door and basement ground heat storage effects has been developed to assess the feasibility of the proposed passive space air-conditioning. It is shown that for no-ventilation summer nights the inside air temperature remains higher than the ambient air temperature even with an effective roof cooling system, and hence the windows should be opened to lose the internal heat and to introduce cool and fresh outside air. It is found that for a ventilation-controlled building with a roof pond the passive solar air conditioning can be achieved more effectively.     

Performance of a solar-regenerated liquid desiccant ventilation pre-conditioning system

A solar-regenerated liquid desiccant ventilation pre-conditioning system has been proposed for use in hot and humid climates. The system aims to dehumidify the ventilation air which is the major source of latent load. A heat exchanger is used to cool the dehumidified air instead of typical evaporative cooling to maintain the dryness of the air. The use of solar energy at the regeneration process and cooling water from a cooling tower makes the system more passive. The simulation procedure for the proposed system has been presented. By inputting the climatic data and the physical parameters of all equipments, the operating parameters at each equipment and the performance parameters of the system can be evaluated. The simulation procedure is demonstrated by showing the daily profiles of the operating and performance parameters on a typical day as well as investigating the influence of the selected operating parameters on the system performance. The results suggest that the most influential parameters are solar radiation, ventilation rate, and desiccant solution concentration. The balance between the water removed at the dehumidifier and that evaporated at the regenerator needs to be considered to maintain uniform performance during continuous operation.     

被动式太阳房降温措施研究

被动式太阳房的冬季采暖效果无可厚非,但是夏季降温措施没有很好的得以解决。通过对前人经验的归纳总结,探讨被动式太阳房解决过热问题的措施,论述太阳能烟囱强化通风降温、绿化降温和长波辐射降温的原理及其效果,并对被动式太阳房降温方案做了简略设计。     

Experimental study of cooling effects of a passive evaporative cooling wall constructed of porous ceramics with high water soaking-up ability

As a passive cooling strategy aimed at controlling increased surface temperatures and creating cooler urban environments in summer, the authors developed a passive evaporative cooling wall (PECW) constructed of porous ceramics. These ceramics possess a capillary force to soak water, which means that their vertical surface is wet up to a level higher than 100 cm when their lower end is placed in water. The present paper describes an experiment that clarifies the cooling effects of a prototype PECW constructed of pipe-shaped ceramics. The PECW is capable of absorbing water and allows wind penetration, thus reducing its surface temperature by means of water evaporation. Passive cooling effects such as solar shading, radiation cooling, and ventilation cooling can be enhanced by incorporating PECWs into the design of outdoor or semi-outdoor spaces in parks, pedestrian areas and residential courtyards. The following findings were understood from an experimental data collected over a summer period. Wet vertical surfaces of the ceramic pipe reached a height of over 1 m at an outdoor location exposed to solar radiation. Wet surface conditions can be maintained throughout successive sunny days during summer. A slight difference in the vertical surface temperatures of the ceramic pipe was found. The air passing through the PECW was cooled, and its temperature can be reduced to a minimum value by several degrees during summer daytime. It was also found that the surface temperature of the shaded ceramic pipe can be maintained at a temperature nearly equal to the wet-bulb temperature of outdoor air.     

Modeling and analysis of a fan–pad ventilated floricultural greenhouse

The application of greenhouse technology in the field of floriculture is rapidly expanding worldwide. In India solar radiation is abundant and the climate in the plains are rather hot and dry in summer months while the coastal parts witness a hot and humid climate. For greenhouses in such climates, cooling and ventilation are major factors influencing the production of quality flowers. In the present paper a thermal model of a greenhouse is presented based on fan–pad evaporative cooling. Thermal performance of the greenhouse, as predicted by the model under different climatic conditions is analyzed and compared with a reference study available in the literature. The analysis reveals that a suitable combination of evaporative cooling, shading and ventilation arrangements can effectively maintain the inside microclimate of the greenhouse within permissible limits throughout the year.     

Design and thermal performance of a passive cooled building for the semiarid climate of India

This communication presents design and thermal performance of a hostel building using passive cooling approaches at Jodhpur in India. Jodhpur is a representative of the semiarid climate in India where, in summer, on average, ambient air temperature is 34.4 °C, relative humidity is 28% and substantial wind in the southeast direction is present. A thermal model, based on Fourier series (in time) expansions of solar insolation and ambient air temperature, is developed and applied to study the effectiveness of various cooling approaches such as a wind tower, a desert cooling fan and evaporative cooling on the roof. Numerical calculations show that the best cooling occurs in the rooms which are partially underground and when the roof is treated by evaporative cooling. The living room becomes thermally very compartable when roof evaporative cooling is used along with a desert cooling fan.     

Application of night cooling concept to social housing design in dry hot climate

A passive night cooling system was developed and implemented for a new project of social housing. The passive cooling system incorporates a solar chimney in combination with high thermal mass in the building construction. The natural ventilation is enhanced with the help of the solar chimney and night fresh air cools the building structure. The design of this concept was calculated by balancing energy using basic thermal equations for a summer reference day and evaluated using two simulation tools, TRNSYS and TAS. The building has been constructed and actually in process of monitoring.