Prospective techniques of effective daylight harvesting in commercial buildings by employing window glazing, dynamic shading devices and dimming control—a literature review

Over a few decades, daylighting has been perceived to possess good potential for energy conservation. In this perspective, there have been significant advances in research methodologies and technologies for optimizing energy consumption through daylight harvesting in commercial buildings. In light of this, a thorough understanding of the application of available technology is very important for daylighting practices for building energy management. The objective of this paper is to examine the status of published research on three key building parameters: window glazing area, dynamic shading devices, and daylighting controls playing a rule on energy conservation. This article may serve as a coherent literature survey that would provide better understanding of the subjacent issues and possibly rejuvenate research interest in this immensely potential field of energy engineering.     

Field study on indoor thermal environment in an atrium in tropical climates

Solar penetration through the transparent envelope can severely deteriorate indoor thermal environment inside an atrium building particularly in tropical climates. This paper reports the application of two low-cost measures, namely high level internal solar blinds and water spray, to minimise overheating problems on the three levels inside the atrium of a guesthouse in Southern China, where summer is hot and humid. The blinds reduce direct solar penetration at the top of the atrium whilst the evaporative spray system cools down the glazed surfaces of the atrium envelope. A site test was undertaken over 10 consecutive days covering both overcast days and clear days in July 2004. Measurement of indoor thermal environmental parameters was conducted on three levels in the atrium and the recorded data represent the internal conditions: with and without internal blinds protection from solar, and with and without water spray. This study has shown that on hot and clear summer days, with water spray and without blinds the average air temperature difference from 1200 to 1800 h between both first floor and second floor, and second floor and external were 5.7 and 1.7 K, respectively; whilst with blinds and without water spray the average air temperature differences were 8.7 and 4.8 K, respectively.     

绿色建筑的表皮材料设计——虹桥商务核心区9号地块外立面设计浅析

以材料为元素表达建筑师对绿色建筑的理念和整体外观的构思已越来越成为潮流与发展趋势。本文介绍了虹桥核心区九号项目设计中所选用到的两种材料．并从绿色节能效果、美学效果、细部处理及表面肌理、施工构造等方面作了探讨分析。     

遮阳金属百叶帘隔热性能实验研究

为研究遮阳金属百叶帘的隔热性能,本文通过模拟太阳光源的遮阳系数测试平台,对3 mm透明玻璃的得热系数、遮阳金属百叶帘的遮阳系数和不同状态下3 mm透明玻璃内外表面温度进行了测试与分析。分析结果表明：遮阳金属百叶帘关闭状态时能阻挡约87%的太阳辐射热量、水平状态时能阻挡约43%的太阳辐射热量,分析结果对遮阳金属百叶帘的实际隔热效果评价具有指导意义。     

Automated blind control to maximize the benefits of daylight in buildings

Venetian blinds are a common type of shading device and are increasingly operated automatically to overcome the limitations of manual operation. Automated blinds need to be controlled to maximize benefits of daylight in the point of occupant comfort and energy consumption. However, the previous control methods are focused on minimizing negative impacts of daylight, so they might fail to maximize positive impacts of daylight. They may often overpredict a blind's position, resulting in the undesirable blockage of daylight.     

Energy performance assessment of double-skin façade with thermal mass

To mitigate the overheating problem in the warmer seasons, and thereby improve thermal performance and energy efficiency of the double-skin façade (DSF) system, this study introduced an innovative design approach involving the integration of passive thermal mass technique with the air channel of the conventional DSF. To assess the contribution of this integration to energy efficiency of the system, a numerical model was developed, capable of determining the thermal performance of the conventional DSF. The numerical model is composed of airflow and thermal models. This paper briefly describes the development of the models as well as the models’ verifications. Models were then used to carry out a series of parametric studies to investigate the effect of thermal mass on the energy performance of the integrated system.The simulation results revealed that mechanically ventilated DSF can save energy based on configuration from 21% to 26% in summer and from 41% to 59% in winter as compared to conventional DSFs without thermal mass. The results also showed the total saving for a naturally ventilated DSF is negligible year-round.     

铝合金百叶帘与建筑外遮阳

外遮阳铝合金百叶帘不仅可隔热、调光、反射紫外线,且耐侯性佳、轻质高强、色彩丰富,适用于新建建筑配备或既有建筑改造。是一种节能效果显著、发展前景广阔的新型建筑节能设施。     

百叶外遮阳太阳散射辐射计算模型及程序实现

窗户外部的遮阳系统可以减少进入室内的太阳辐射得热量。目前,在计算遮阳系统对太阳辐射的遮挡作用时,仅仅从几何角度上考虑遮阳构件对直射辐射的减少作用,没有考虑对散射辐射的影响,但在实际中,遮阳构件的存在,对散射辐射的影响不能忽略,特别是对于百叶类型的遮阳构造,由于其布置较为紧密,对直射辐射遮挡较多,进入室内的太阳辐射主要为散射辐射,因此建立详细的散射辐射计算模型。可以正确反映和评估其遮阳效果,并为计算遮阳构件对建筑能耗的影响提供基础。通过分析散射辐射入射到百叶遮阳板上的光学特性,建立用于计算太阳散射辐射透过和反射的数学模型,并根据该模型得到用于计算机编程的算法。该模型和算法可以应用于不同的百叶遮阳系统,为建筑能耗模拟中考虑百叶遮阳板对空调能耗的影响提供理论基础。     

遮阳金属百叶帘隔热性能实验研究

为研究遮阳金属百叶帘的隔热性能,本文通过模拟太阳光源的遮阳系数测试平台,对3mm透明玻璃的得热系数、遮阳金属百叶帘的遮阳系数和不同状态下3mm透明玻璃内外表面温度进行了测试与分析。分析结果表明:遮阳金属百叶帘关闭状态时能阻挡约87%的太阳辐射热量、水平状态时能阻挡约43%的太阳辐射热量,分析结果对遮阳金属百叶帘的实际隔热效果评价具有指导意义。