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 共查询到19条相似文献,搜索用时 218 毫秒
1.
外墙保温技术对空调负荷的影响   总被引:8,自引:0,他引:8  
采用建筑热环境模拟工具DeST对同一住宅建筑进行模拟计算,分析了不同气候地区外墙保温形式及保温层厚度对空调负荷的影响,并讨论了空调运行模式及自然通风模式的影响,可为不同气候地区的住宅建筑外墙隔热保温设计提供依据。  相似文献   

2.
空调建筑外墙和屋顶经济绝热厚度的计算   总被引:3,自引:0,他引:3  
该文介绍了种计算空调建筑外墙和屋顶经济绝热厚度的模型。该模型根据热流通过不同组件时间的相关分析并运用Lagrange乘子法,计算了不同增初投资额条件下外墙和屋顶的经济绝热厚度。运用该模型,依据上海、南京、武汉和重庆的气候参数对一典型住宅建筑进行了数值计算。计算结果表明,从经济评价角度来看,外墙保温隔热宜采用各热材料价格和气候因素对外墙和屋顶绝热材料厚度取值的影响。  相似文献   

3.
隔热涂层降低建筑顶层空调动态负荷的数值模拟   总被引:1,自引:1,他引:0  
建立了屋顶和南外墙涂敷隔热涂层的房间的非稳态传热模型.利用该模型探讨了隔热涂层对房间空调动态负荷、日制冷量和室内热环境的影响,并采用北京、合肥、深圳3地夏季月平均气象数据,对当地建筑使用隔热涂层的节能效果进行了评估.研究发现:给建筑顶层外表面加装隔热涂层可显著降低房间空调负荷和日制冷量;整个夏季的空调平均日制冷量随地区的不同可降低40.0%~60.1%;隔热涂层还能显著降低房间外表面和内表面(尤其是天花板)温度的峰值和波幅,在节能的同时可改善室内热环境.  相似文献   

4.
刘付林  潘玉勤  杜永恒 《节能技术》2010,28(2):158-164,186
屋面作为建筑外围护结构保温隔热体系的一个重要组成部分,其保温隔热性能直接影响到建筑保温隔热性能及其能耗。本文根据国家"十一五"科技支撑计划项目"村镇建筑节能及改善室内热环境关键技术研究"中对河南地区村镇建筑围护结构的调查结果,归纳总结了不同时期、不同材料、不同构造做法的村镇建筑的屋面形式的保温隔热性能,依据试验数据对比得出不同材料及构造做法的保温隔热性能的优劣,从农村建筑的经济、技术、材料、节能意义等方面分析了屋面保温隔热技术在我国广大农村推广实施的重要性和必要性,并对建筑材料的发展方向和趋势提出了建议和意见。  相似文献   

5.
研制了遮阳板与集热器一体化的新型太阳能相变集热器,通过搭建的实验测试平台对其集热性能及隔热特性进行了实验测试。该建筑构件具备遮阳隔热及太阳能集热功能,为在建筑中高效利用太阳能,实现太阳能与建筑一体化提供一种新的工程应用模式。通过实验测试,对该集热器在不同工况下的集热性能、隔热特性及其影响因素进行了系统分析研究,提出了该集热器的累积集热量、集热效率、隔热特性等性能评价指标。测试结果表明,遮阳板式太阳能相变集热器的平均集热效率可达12.3%,隔热效果优于普通遮阳板。  相似文献   

6.
太阳墙热特性分析   总被引:3,自引:0,他引:3  
杨昭  徐晓丽  韩金丽 《太阳能学报》2007,28(10):1091-1096
对改进的特朗勃墙进行热过程分析,采用CFD技术耦合流固传热求解控制方程,研究了该太阳墙的动态热特性及在冬夏季华北典型气象条件的集热、保温、隔热及预热特性。同时,对墙体材料、墙体高度、空气层厚度、通风孔尺寸等敏感因子进行了分析,给出了适宜的墙体材料及构造形式。所得结论将有利于推进太阳能—建筑一体化技术的发展。  相似文献   

7.
创造健康舒适的生活环境是人类共同的愿望,也是建筑节能的基础和目标。采用新技术对建筑围护结构进行高水平的保温隔热是达到现行住宅节能设计标准提出节能50%的主要措施。在外墙使用高效保温材料的复合墙体是墙体节能的主要发展方向。针对墙体外保温和内保温的不足,设计出了一种新型的复合保温砌块。利用防护热箱法和数值模拟方法得到了砌块热绝缘系数最大时的砌块的结构。并对该种砌块的保温性能、隔音性能和经济性进行了初步研究,论证了此种砌块所具有的优越性及推广应用的可行性。  相似文献   

8.
《节能》2019,(11):17-20
对大庆市杜蒙县杏树岗村的农宅外墙节能进行研究,发现农村住宅外墙大多采用无保温37黏土砖墙,采暖期的室内舒适度低,能耗高。在Ecotect中建立建筑模型,通过逐时温度曲线和逐月能耗模拟2个方面对农宅的外墙进行能耗分析,提出外墙保温层厚度设计最优值,得出大庆市农宅的外墙采用55 mm聚苯乙烯泡沫板作为外保温系统最为经济和节能,为寒地农宅室内热环境优化提供指导。  相似文献   

9.
从室内热环境的要求入手,通过外墙的不同构造,对夏季隔热、冬季保温进行了全面分析研究,为适应小城镇经济特点,利用当地资源条件,改善夏热冬冷地区小城镇住宅室内环境提供节能措施。  相似文献   

10.
通过对建筑材料全寿命周期成本效益的分析,采用技术经济综合评价方法,紧扣外墙节能材料的环保性、适用性、经济性、耐久性和使用舒适性,构建建筑外墙节能材料适用评价指标体系,并以华中地区常用外墙保温材料为例进行实证分析,为基于全寿命周期经济评价的外墙节能材料优选提供参考。  相似文献   

11.
针对太阳能富集地区居住建筑外墙构造特点和室外综合温度条件,以拉萨地区为例进行研究,提出了采暖居住建筑非平衡保温节能墙体构造,其中南墙不做保温、东西墙和北墙采用外保温。在对当地典型居住建筑形式和围护结构现状调研基础上,采用南墙兼顾延迟时间和传热系数,东西墙、北墙单位面积等净失热量的分析方法,确定了非平衡外墙的传热系数,并对以此设计的非平衡保温构造总净热损失和内表面温度进行了分析。给出了非平衡保温构造的计算与分析方法,为同类地区非平衡保温构造设计提供了方法和理论依据。  相似文献   

12.
衣健光 《节能技术》2006,24(4):337-341
本文对执行《公共建筑节能设计标准》(GB 50189-2005)中几个常见的重要问题进行探讨,包括围护结构热工性能参数分类、建筑朝向判别、外墙平均传热系数计算、地面和地下室热阻计算。  相似文献   

13.
The term “open-joint ventilated façades” refers to a building system in which coating material (metallic, ceramic, stone or composite) is hanged by means of a metallic-frame structure to the exterior face of the wall, creating an air cavity between wall and slabs. The coating material is placed in an arrangement of slabs and a series of thin joints from slab to slab to allow the surrounding air to enter and leave the cavity all along the wall. In addition to aesthetic and constructive reasons, the main interest in open joint ventilated façades is their ability to reduce cooling thermal loads. This is achieved by the buoyancy effect induced by solar radiation inside the ventilated cavity, where the air can enter or leave freely through the joints. This paper focuses on the phenomena produced on a typical open joint ventilated façade, and the comparison of its energy performance with that of a conventional sealed air cavity façade. The thermo fluid-dynamic behaviour of both systems has been analysed with CFD techniques and the results of the 3D simulations conclude that open-joint ventilated façades can help to achieve important energy savings in climates with hot summers and mild winters.  相似文献   

14.
A coupling configuration of double-wall cooling and exterior surface thermal barrier coating(TBC)is one of the most promising thermal protection methods of hot components of modem gas turbine.The combined influences of coating thickness,impingement layout,and cooling air flowrate on the overall thermal performances of such configuration were discussed deeply,to provide the valuable guidance of design.Overall effectiveness measurements were implemented under engine-matched Biot numbers and mainstream-to-coolant temperature ratio.Conjugate heat transfer simulations provided the additional information difficult to be acquired by the measurements.The results indicated that the contribution of TBC is much larger than that of increasing the cooling air amount.The thicker TBC can produce the stronger insulation,while the higher risk of thermal damage of itself.The larger coolant flowrate enlarges the benefit of TBC,while the trend is suppressed by the thick TBC.The constant coating thickness cannot bring to the uniform metal temperature,which can be solved through properly adjusting the backside impingement.The trends in overall effectiveness with TBC’s thickness are independent on the change of internal impingement.  相似文献   

15.
A numerical model is presented to determine the thermal shielding performance of an exterior wall (e.g., building envelope) containing layers of PCMs. The model is exploited to perform a parametric study to assess the influence of the position and melting temperature of one PCM layer. Results showed that benefits are to be expected when the interior and exterior temperatures are close. Then, the wall composition has been optimized with a genetic algorithm based on a yearly analysis with the possibility of including several PCM layers. Idealized weather conditions and measured weather conditions (including solar radiation) have been considered. Results showed that for Québec City, optimal south-facing wall includes one PCM layer when real weather data are considered. Its effect is to shield the heat transfer in the summer. This paper provides a fundamental understanding of multilayer walls with PCMs.  相似文献   

16.
以一栋典型干打垒建筑为研究对象,为解决其保护不善问题,提出了多种因素、多个目标综合分析的保护性低碳节能改造策略。建立干打垒建筑信息模型,为后续改造和管理提供数据支撑。在不影响文化和历史价值的基础上,研究了在外墙和屋顶上添加内保温材料以及更换外窗。考虑保护方法、U值限制和当地材料等因素,选取了6种保温材料和4种窗户类型,建立了24种工况。分别模拟和估算各个工况的能耗、碳排放和生命周期成本。基于节能、低碳及经济三个目标,采用分类比较与综合比较相结合的方法评价各个工况。结果表明,采用发泡聚苯乙烯(EPS)和90系列隔热铝合金窗,能耗、碳排放及成本最低,是最佳方案。该优化方法可以促进既有建筑创新节能和低碳改造方法的发展。  相似文献   

17.
Thermal analysis of a direct-gain room with shape-stabilized PCM plates   总被引:1,自引:0,他引:1  
The thermal performance of a south-facing direct-gain room with shape-stabilized phase change material (SSPCM) plates has been analysed using an enthalpy model. Effects of the following factors on room air temperature are investigated: the thermophysical properties of the SSPCM (melting temperature, heat of fusion and thermal conductivity), inner surface convective heat transfer coefficient, location and thickness of the SSPCM plate, wall structure (external thermal insulation and wallboard material) etc. The results show that: (1) for the present conditions, the optimal melting temperature is about 20 °C and the heat of fusion should not be less than 90 kJ kg−1; (2) it is the inner surface convection, rather than the internal conduction resistance of SSPCM, that limits the latent thermal storage; (3) the effect of PCM plates located at the inner surface of interior wall is superior to that of exterior wall (the south wall); (4) external thermal insulation of the exterior wall obviously influences the operating effect and period of the SSPCM plates and the indoor temperature in winter; (5) the SSPCM plates create a heavyweight response to lightweight constructions with an increase of the minimum room temperature at night by up to 3 °C for the case studied; (6) the SSPCM plates really absorb and store the solar energy during the daytime and discharge it later and improve the indoor thermal comfort degree at nighttime.  相似文献   

18.
The aim of this study is to determine how time lag and decrement factor are affected by wall orientation and exterior surface solar absorptivity, for specific climatic conditions. Their influence forms a non-sinusoidal periodical forcing function that simulates suitably the outdoor temperature fluctuations. This novel approach, allows the predictability of building's thermal response in an efficient way. The investigation is carried out for various insulated opaque wall formations comprising typical material elements, during the summer period in the mild Greek region. This study that allows proper building planning procedures, at the very early stages of the envelope design, presents great importance. The analysed configurations are assumed to have an orientation that corresponds to each compass point. In addition, the solar absorptivity of surface coatings is assumed to be varying from 0 to 1. The transient thermal analysis is obtained via a thermal circuit that models accurately the fundamental heat transfer mechanisms on both boundaries and through the multi-layered wall configurations. Moreover, the mathematical formulation and solution of this lumped model is achieved in discrete time steps by adopting the non-linear nodal method. The simulation results are focused on the single and combined effects of orientation and solar absorptivity on the dynamic thermal characteristics of various wall configurations.  相似文献   

19.
As the variation and timely meeting thermal environment requirement of indoor air temperature has a close relationship with the thermal performance of building external wall under discontinuous radiant heating condition, one appropriate assessment method or index for assessing the building external wall thermal performance is very necessary. In order to reasonably evaluate the thermal performance of external wall under discontinuous radiant heating condition and build the direct connections and interactions among the indoor air temperature, external wall inner surface temperature and outdoor air temperature, the first and second impact factors of temperature deviation were established, based on one mathematical model of room heat transfer. For one experimental room and four types of external walls under discontinuous radiant heating condition, both the influence of the external wall inner surface temperature deviation on the indoor air temperature and that of the outdoor air temperature deviation on the external wall inner surface temperature were determined effectively with the first and second impact factors of temperature deviation. In addition, favourable performance for the self-insulation and inner insulation walls were found, due to their superiority in effectively and timely improving the indoor thermal environment under discontinuous radiant heating condition.  相似文献   

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