酒店中庭空间体量对热环境和能耗的影响研究——以京津地区带天窗酒店建筑中庭为例

通过实地调查,分析寒冷地区冬夏两季酒店建筑带天窗中庭空间的热环境现状。结合计算机软件对典型工况的模拟结果,研究空间体量对带天窗中庭空间热环境和能耗的影响机理,并提出降低建筑能耗的设计优化建议。研究表明:中庭空间上部相对更易受到室外环境影响;空间高度变化影响中庭对太阳辐射热的利用情况,进而影响其热环境和能耗状况;合理降低中庭能耗,应考虑在满足相应空间设计要求的前提下,尽量减小中庭体量,控制中庭高度。     

中庭天窗性能对办公建筑能耗的影响

以有中庭天窗的典型办公建筑物为例,分析天窗面积比和工程中常用玻璃对不同气候分区中庭夏季太阳辐射得热、中庭空调冷热负荷及能耗、建筑能耗的影响。结果表明,天窗面积比和玻璃性能对中庭夏季太阳辐射得热、中庭空调冷热负荷及能耗的影响较大,而对整个建筑能耗的影响较小。与传热系数相比,遮阳系数对负荷、能耗的影响更大。建议设计时将天窗面积比控制在10％以下,同时应选择性能较好的玻璃,必要时应设置外遮阳。     

建筑采光中庭能耗控制的空间形态构成影响因子研究

建筑能耗的控制有被动式和主动式两种基本方式。而作为被动式能耗控制的基础,采光中庭的空间形态构成将对建筑能耗的控制有直接的影响。采光中庭的存在必须有四个必要的基本条件：室外环境、母体建筑、采光界面和采光中庭自身的构成方式。本文将从这四个方面展开,研究采光中庭空间形态构成的影响因子,进而研究其能耗的特点。     

围护结构热工参数与中庭类建筑冷负荷相关性分析

以广州某一设有中庭的大型建筑为对象建立模型,采用正交分析方法,研究了建筑外围护结构平均窗墙面积比、中庭屋顶天窗面积比、建筑外围护结构平均热惰性指标、建筑外围护结构平均传热系数与建筑冷负荷、中庭冷负荷的相关性。结果表明,建筑外围护结构平均传热系数与建筑能耗中度相关,与中庭能耗低度相关。影响中庭能耗的主要因素是中庭屋顶天窗面积比。     

不同气候区中庭天窗性能对办公建筑能耗的影响

以有中庭天窗的典型办公建筑为例,分析天窗面积比和工程中常用玻璃对不同气候分区中庭夏季太阳辐射得热、中庭空调冷热负荷及能耗、建筑能耗的影响.结果表明,天窗面积比和玻璃性能对中庭夏季太阳辐射得热、中庭空调冷热负荷及能耗的影响较大,而对整个建筑能耗的影响较小.与传热系数相比,遮阳系数对负荷、能耗的影响更大.建议设计时将天窗面积比控制在10%以下,同时应选择性能较好的玻璃,必要时应设置外遮阳.     

考虑排风利用的某中庭热环境与节能性研究

以上海地区某商业建筑中庭为例,分析将内区办公区温度较低的排风引入中庭的措施,对中庭内温度及空调系统能耗的影响。重点分析了夏季不同排风策略及排风风量对中庭内温度分层及系统能耗的影响。研究结果表明,夏季宜尽量利用内区排风冬季宜关闭,且开启顶部排风对中庭内温度影响显著,此措施能够改善中庭上部温度并有效减小能耗。     

基于设计视角,浅析公共建筑中庭空间自然通风的影响因素

中庭在现代建筑中不仅起着起着沟通室内空间和室外环境的缓冲作用,它同时也在建筑空间设计和建筑节能设计中占据着举足轻重的位置。据研究,在我国大空间建筑面积占全国建筑总面积的5%但能耗却占全国20%。而在各类建筑中,空调能耗又占60%左右。因此,引用自然通风改善空间品质,降低建筑能耗,更具有现实意义。本文通过对厦门当地中庭建筑进行调查研究,归纳和分析中庭内在通风的影响因素。从中庭形式和中庭面积占有率,剖面空间形态,底层空间形态,顶层空间形态等几个方面,分析影响建筑中庭自然通风设计的主要因素。     

中庭自然通风技术用于医院建筑的节能设计研究——以广州市某医院为例

目前医院建筑能耗远高于其他类型公共建筑,其中为保证室内空气品质及新风量要求的机械通风能耗占了很大比重。通过合理设计中庭形式,使尽量采用自然通风技术来保证医院建筑对新风量及室内空气品质的要求成为可能。本文在分析医院建筑能耗特点的前提下,提出了中庭通风策略,并以广州某医院为例,研究中庭结构对门诊楼通风质量的影响,为医院建筑的节能设计提供理论基础。     

净零能耗建筑中庭玻璃屋顶对中庭空间温度竖向分布影响

为研究净零能耗建筑中庭玻璃屋顶对中庭空间温度竖向分布影响,运用自动气象站TRM-ZS2型1台,高精密度智能温度记录仪A0678933/179A-T2仪器3台,依据测试项目情况,选取某综合楼中庭空间作为测试对象,选择夏季连续3d晴天进行测试,以此来测试XIR夹胶玻璃对中庭空间竖向温度分布的影响。这些研究成果可为净零能耗建筑技术提供参考和借鉴。     

基于节能的办公建筑采光中庭形态优化设计

采光中庭由于其独特的空间设计给人们带来不一样的视觉感受,已在办公建筑中广泛应用,中庭结构的合理设计对建筑自然采光、建筑能耗具有很大的影响。通过Autodesk Ecotect和Ra-diance数值软件,模拟计算不同中庭平面布局、尺寸比例以及幕墙朝向对办公建筑自然采光系数、全年自然采光满足率DA、天然采光照明节能率、室内照度全年满足率的影响;在模拟分析的基础上,采用Designbuilder数值软件比较分析采光中庭形态优化设计对办公建筑人工照明、采暖空调能耗的影响。     

Study on simulation methods of atrium building cooling load in hot and humid regions

In recent years, highly glazed atria are popular because of their architectural aesthetics and advantage of introducing daylight into inside. However, cooling load estimation of such atrium buildings is difficult due to complex thermal phenomena that occur in the atrium space. The study aims to find out a simplified method of estimating cooling loads through simulations for various types of atria in hot and humid regions. Atrium buildings are divided into different types. For every type of atrium buildings, both CFD and energy models are developed. A standard method versus the simplified one is proposed to simulate cooling load of atria in EnergyPlus based on different room air temperature patterns as a result from CFD simulation. It incorporates CFD results as input into non-dimensional height room air models in EnergyPlus, and the simulation results are defined as a baseline model in order to compare with the results from the simplified method for every category of atrium buildings. In order to further validate the simplified method an actual atrium office building is tested on site in a typical summer day and measured results are compared with simulation results using the simplified methods. Finally, appropriate methods of simulating different types of atrium buildings are proposed.     

A comparison of winter pre-heating requirements for natural displacement and natural mixing ventilation

In winter, natural ventilation can be achieved either through mixing ventilation or upward displacement ventilation (P.F. Linden, The fluid mechanics of natural ventilation, Annual Review of Fluid Mechanics 31 (1999) pp. 201-238). We show there is a significant energy saving possible by using mixing ventilation, in the case that the internal heat gains are significant, and illustrate these savings using an idealized model, which predicts that with internal heat gains of order 0.1 kW per person, mixing ventilation uses of a fraction of order 0.2-0.4 of the heat load of displacement ventilation assuming a well-insulated building. We then describe a strategy for such mixing natural ventilation in an atrium style building in which the rooms surrounding the atrium are able to vent directly to the exterior and also through the atrium to the exterior. The results are motivated by the desire to reduce the energy burden in large public buildings such as hospitals, schools or office buildings centred on atria. We illustrate a strategy for the natural mixing ventilation in order that the rooms surrounding the atrium receive both pre-heated but also sufficiently fresh air, while the central atrium zone remains warm. We test the principles with some laboratory experiments in which a model air chamber is ventilated using both mixing and displacement ventilation, and compare the energy loads in each case. We conclude with a discussion of the potential applications of the approach within the context of open plan atria type office buildings.     

Validation of computational fluid dynamics simulations for atria geometries

Atria are becoming an increasingly common feature of new buildings. They are often included for their aesthetic appeal; however, their effect on building indoor environment can be significant. Building simulation tools have the potential to assist designers in enhancing energy efficiency by providing information on the temperature and velocity fields inside the atrium for specified geometries and ambient conditions. The unique nature of the physical phenomena that govern the complex flows in atria, however, are not usually considered in traditional building energy simulation programs. These physical phenomena include turbulent natural convection, radiative heat transfer and conjugate heat transfer. Computational fluid dynamics (CFD) has the potential for modeling fluid flow and heat transfer resulting from the phenomena; however, careful validation is required in order to establish the accuracy of predictions. This paper provides a systematic validation of a commercial CFD code against experimental measurements of the underlying physical phenomena. The validation culminates in the simulation of an existing atrium. This work indicates that CFD can be used to successfully simulate the heat transfer and fluid flow in atria geometries and provides recommendations regarding turbulence and radiative heat transfer modeling.     

Comparative analysis of energy performance between courtyard and atrium in buildings

In this paper, the energy performance of a central atrium is investigated and compared with the energy performance of a courtyard with the same geometric proportions. The atrium and the courtyard design used for the analysis are square in plan and surrounded by the building on all four sides. The glazing type and percentage for the courtyard walls and atrium skylight are varied in the analysis. Weather data from four cities representative of climatic conditions of cold, temperate, hot-humid and hot-dry were used. The results show that, in general, the open courtyard building exhibits a better energy performance for the shorter buildings. As the building height increases, however, at some point the enclosed atrium exhibits a better energy performance. This “break even” point for the number of stories depends on different factors like glazing and climate parameters discussed above.     

Luminous impact of balcony floor at atrium spaces with different well geometries

The atrium concept allows the exploitation of daylighting by bringing natural light into the center of the buildings, thus enhancing a more even distribution of daylight. The configuration of interior balconies, however, is determined based on the purpose of the interior space and the use of the building, which may defeat the primary daylighting advantages inherent in the atrium concept. The authors have developed insights regarding the critical daylighting performance factors by evaluating the relative effect of various interior balcony configurations on illumination level and its distribution with different atrium geometries. For these, parametric measurements of illumination level with a scale model of a four-sided atrium building and various interior balcony configurations have been conducted under diffuse sky conditions within the sky simulator at a Texas university. This paper represents the atrium performance results in terms of daylight factor, Well index, balcony Well index, the configuration of interior balcony; and the results are compared with basecase atria without any interior balcony. As expected, Well index and balcony depth are the most significant factors in daylighting performance in atrium spaces with interior balconies. For the position not covered by balcony, adequate illumination can be achieved for circulation regardless of building Well index and balcony depth although it may be that involved well indices are relatively low. On the other hand, light attenuation on the position under balcony floor is up to 70–90%, in particular, when the Well index becomes higher than 1 m and balcony floor becomes deeper than 3 m.     

Assessing and predicting average daylight factors of adjoining spaces in atrium buildings under overcast sky

Daylight use in an atrium is particularly beneficial as the natural light can illuminate potentially dark core areas and decrease energy consumption from electric lighting. This study has investigated, for overcast sky conditions, the horizontal daylight levels in spaces adjoining atria and the vertical daylight levels on atrium well walls in atria. The daylight levels in the rooms and on the walls were derived from scale model measurements, theoretical calculations and predictions from the lighting simulation package Radiance. A comparison of measured data and modelling has validated Radiance simulations of atrium daylighting. The simulations show generally good agreement with theory while some limitations in the calculations used in determining the daylight factors in rooms with large widow area to total wall area ratios were observed. The average daylight levels in rooms displayed a linear relationship with the vertical daylight levels on the well wall. In terms of the well geometry and well façades (decided by the ratio of window area to solid wall area) and well surface reflectance, the variations of daylight level in the adjoining rooms have been analysed and some conclusions and design strategies for supporting preliminary design decisions are presented.     

自然通风环境下办公建筑中庭空间热舒适性模糊优化研究

：随着绿色建筑设计理念深入人心,办 公建筑的中庭空间因其特有空间特质受到越来 越多的关注。通常办公中庭空间中的节能性与热 舒适性是一对矛盾体,而自然通风作为被动节能 技术之一,不仅能够促进中庭空间的内外空气 循环,改善室内空气质量,而且降低能耗和提升 热舒适性,较好地解决这一矛盾。以江雅园办公 楼中庭空间为案例进行研究,从中庭屋顶形态、 中庭高度及进风口开启方式三个变量因素出发, 引用模糊评估方法寻找出中庭空间自然通风热 舒适性最佳方案,结论显示在多个组合方案中 斜屋顶形态+进风口全部开启的方案热舒适性最 佳,同时也证明屋顶形态与通风方式的变化对自 然通风舒适性的影响较大,而中庭空间高度的变化对自然通风舒适性影响较小。本研究希望建立一套以风速和温度为评价指标的模糊体系,为自 然通风的热舒适性的评价提供一种客观的评估手段,从而为方案阶段的中庭空间设计提供一种 有效的优化方法。     

中庭火灾烟气流动的大涡模拟

采用大涡模拟的方法,对中庭火灾烟气的流动过程进行了模拟,了解了中庭烟气的蔓延过程,得到了烟气的速度场和温度场、顶棚射流的速度和温度的详细结果。模拟结果表明,大涡模拟能比较准确地预测中庭内烟气的流动状态,可用于指导中庭建筑的防火设计。     

Analysing the impact of reflectance distributions and well geometries on vertical surface daylight levels in atria for overcast skies

This study investigated the impacts of different diffuse reflectance distributions and well geometries on vertical daylight factors and vertical internally reflected components in atria. Two forms of reflectance distribution patterns of wall surface were examined: horizontal and vertical reflectance band variation. The square atrium models studied have a broader WI range of 0.25–2.0, which represent shallow, medium and high atria. Radiance, a powerful package based on backward ray tracing technique, was used for the simulations of vertical daylight levels. The results show that different reflectance distributions of square atrium walls do have an impact on the vertical daylight factors and vertical internally reflected components under overcast sky condition. The impact relates to the orientation of the band with different reflectance distributions on the wall. Compared with the vertical band surface, the horizontal band surface has a much more complicated effect. The horizontal distributions of the reflectances significantly affects the vertical daylight levels at the locations more than 30% atrium height on the wall. For an atrium with a height more than 1/2 the width, the effect tends to increase with the increasing well index. The vertical distributions of the reflectance, nevertheless, do not substantially take effect on the vertical daylight levels in atria except for some special reflectance distribution patterns.     

四向建筑中庭天然采光与建筑设计的研究

天然采光有利于节省照明能耗,改善建筑空间的光环境质量.通过研究四向建筑中庭的形状、中庭高度、中庭面积、中庭的天窗面积、玻璃材料与中庭天然采光之间的关系,为建筑师设计中庭提供了理论依据.