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粗放型屋顶绿化隔热效果分析 总被引:2,自引:0,他引:2
以自然通风层的屋顶绿化为研究对象,对有无绿化屋顶内表面温度进行比较,采用实测数据统计分析的方法,以全夏季为研究周期,按不同温度区间分析屋顶内表面温度的分布特性,比较2种状态下屋顶内表面温度的分布频率以及总温度,得到绿化屋顶内表面温度<34 ℃出现的频率占总周期的90%,是无绿化屋顶的1.6倍,大于36 ℃高温的频率为无绿化屋顶的4.6%,绿化屋顶内表面大于30 ℃的温度总量约为无绿化屋顶的1/3,且绿化屋顶的隔热性能与室外气温有较强的正向性,随着气温的升高,绿化屋顶的隔热性能体现得更加充分。 相似文献
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对福州某小区顶层两不同房间进行屋顶内表面温度、室内气温以及屋顶内表面热流的现场测试,结果表明,绿化屋顶能有效降低屋顶内表面最高温度、室内气温并可有效控制温度变化幅度,其内表面热流的变化幅度也大大小于普通架空屋顶的。绿化屋顶能降低屋顶热损失,改善室内热环境,节省制冷能耗。 相似文献
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自然状态草地式屋顶绿化隔热特性分析 总被引:3,自引:0,他引:3
在夏季自然通风状态下对重庆有绿化屋顶和无绿化屋顶内表面温度和气候参数进行了测量。通过对测量数据的统计分析,得到以下结论:屋顶绿化对降低屋顶内表面最高温度的效果非常显著,降低平均温度效果稍差,热天气有绿化屋顶内表面对空气的总平均增温量为无绿化屋顶的1/4左右;以天为周期,有绿化屋顶内表面对空气的增温量与太阳辐射照度的变化有较强的反向性,以一段晴雨天气为周期,这种反向性减弱,而以整个夏季的热天气为周期,这种反向性转变为很强的正向性;对于无绿化屋顶,无论热作用周期的长短,内表面对空气的增温量与太阳辐射照度的变化都呈现很强的正向性。 相似文献
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绿化屋顶在节能设计中以附加当量热阻增大屋顶总热阻值,有效减少由屋顶进入室内的热量,降低室内空气温度。但根据已有的实验研究,绿化屋顶隔热特性与室内气温是耦合关系,随室内气温的变化,绿化屋顶会呈现出不同的隔热特性。用实验测试与数值模拟相结合的方法,分析在不同室内气温下绿化屋顶、参照屋顶与等效保温屋顶内表面温度与热流的变化。结果表明:室内气温会显著改变绿化屋顶的隔热性能,其当量热阻为与室内温度正相关的变量。在被动式建筑中,绿化屋顶更能充分发挥隔热功效,且具有不向室内传热的特性。 相似文献
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文章以广州白云区西湾路和西槎路一带现代住宅为例,通过对该地区屋顶状况调研与实地测量,通过对比分析,对广州市现代住宅屋顶保温隔热性能进行探讨。 相似文献
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发展屋顶绿化增加城市绿量 总被引:18,自引:2,他引:18
从对城市和城市绿化的认识出发,指出屋顶是绿化现代城市的新领域。通过对屋顶绿化的发展实践和实例分析,研究了屋顶绿化的特点和关键性技术,指出发展屋顶绿化是迅速增加城市绿量、扩大绿化面积的有效途径。 相似文献
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谢浩 《保温材料与节能技术》2007,(3):1-2,15
针对影响通风屋顶隔热效果的因素,提出了提高通风屋顶隔热性能的若干问题,包括合理组织风压通风和热压通风,注意材料的隔热性能,以及利用封闭空气间层等。 相似文献
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随着城市化的快速推进,房屋的外观设计迎来了一个新的发展时期,其中以屋顶花园的发展最为迅速。而近年来,地震灾害频发,城市中楼房的抗震减灾越来越受到人们的重视。研究房屋抗震与屋顶花园结合来提高房屋的抗震性能。利用ADINA软件建立屋顶花园的模型,进行地震动位移响应研究。根据有控模型和无控模型计算结果比较,得到一些有意义的结论。 相似文献
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The curtain wall is being widely adopted in high-rise buildings because of its many advantages. Many researchers have tried to predict the surface temperature of windows or curtain walls precisely. But most of the research has focused on small-scale window rather than large-scale curtain walls. Thus, a study on the correlation between a computer simulation and a mock-up test using a large-scale thermal chamber for the curtain walls is needed. There are three main objectives in this study: first, to understand the reasons for the differences between the results of the thermal mock-up tests and those of the simulations: second, to understand the differences in the simulation methods: and third, to reduce those differences using the method proposed in this study. For 12 curtain walls, the mean temperature difference between computer simulations and the mock-up tests was about 2.6 °C. The simulation method (NFRC) considering convection and radiation showed closer result to the mock-up test than conventional simulation method. This study proposed a method adjusting the simulation result to the test result by changing the convective film coefficients of the frame and glazing to find the optimal convective film coefficients for the chamber. To verify proposed the average convective film coefficients, additional thermal mock-up tests and simulations were performed. The simulation using the average convective film coefficients showed better agreement with the mock-up result. 相似文献
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介绍绿化屋面系统的分类、组成及各自设计特点,并以沈阳市图书馆及儿童活动中心工程为例,详细分析了北方大面积种植绿化屋面设计应考虑的主要因素,展望了绿化屋面设计的广阔应用前景. 相似文献
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Xuefu Zhang Yuanming Lai Wenbing Yu Yaping Wu 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2004,19(1):45-56
According to the in-situ measured data of the air temperature and ground temperature inside of Feng Huoshan Tunnel on Qing-Zang railway, China, the thawed range of the permafrost surrounding the tunnel is very large, which is caused by the hydration heat of the cast-in-situ concrete lining, insulation measurement during winter construction and other artificial activities. In this paper, taking the coupled effects of moisture transfer and heat conduction into account, the finite element formulae of this problem with phase change are derived from the governing differential equations and moisture transfer equations using Galerkin's method and the software for computers is edited. Using the software, forecast analysis for the re-frozen of Feng Huoshan permafrost Tunnel is made. The analysis results indicate that the vault, left wall and right wall of Feng Huoshan Tunnel without the thermal insulation material will be refrozen on 30 September 2004, and the arch bottom will be refrozen on 30 September 2005. However, if the tunnel is fitted with the thermal insulation material whose thermal conductivity is 0.0186(W/m K), the vault of the tunnel will be refrozen on 30 September 2005, and the left wall, the right wall and the arch bottom will be refrozen on 30 September 2006. If thermal conductivity of the thermal insulation material is 0.03(W/m K), the vault of the tunnel will be refrozen on 30 September 2004, and the left wall, the right wall and the arch bottom will be refrozen on 30 September 2005. So, the thermal insulation material will prevent the thawed range of Feng Huoshan permafrost tunnel from being refrozen. The thawed range of the permafrost surrounding the cold region tunnel caused by construction must be taken into account in design and the time of the field observation should be extended, or observational results, such as their temperature and stress field, will greatly be different from results in stability. 相似文献
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本文运用计算机数值模拟方法对窗框、玻璃系统、整窗热工性能进行数值模拟分析。模拟结果表明,窗框中的钢衬、间隔条等因其热阻较小,易在窗框中形成"热桥"效应。Low-E中空玻璃系统传热系数最小,且具有较高的可见光透射比。阳光控制镀膜中空玻璃太阳得热系数SHGC、可见光透射比均较小。同时对样窗进行实验室实际测试,验证了运用数值模拟计算外窗传热系数是一种可行的方法。 相似文献
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Convective heat transfer inside the gap of double glazed windows is studied numerically using a commercial CFD code (Fluent v6.3), for different Rayleigh numbers and aspect ratios. A reference window with empty gap is compared with windows where the gap contains fins arranged in such a way as to reduce heat transfer. The effects of convective air flow inside the cavities were estimated both at the onset of convection and at steady-state in real environmental conditions. The global Nusselt numbers were calculated for different configurations of the fins in the window gap, in order to apply the standard heat loss estimation method to this type of windows. 相似文献