严寒地区近零能耗建筑围护结构热湿传递对室内舒适性影响的研究

近零能耗建筑围护结构是复合多孔介质,研究水分透过墙体对建筑物内部环境的影响机理.以沈阳市某近零能耗建筑为例,采用WUFI-Plus软件对建筑内环境参数进行模拟,比较了考虑热湿传递与不考虑热湿传递对该建筑室内舒适性的影响.结果表明:建筑围护结构的热湿传递作用对室内相对湿度情况影响明显,应在空调设备、系统选型和环境预测分析...     

基于STIRPAT模型的节能建筑围护结构能耗分析

为了提升节能建筑围护结构能耗分析效果,提出基于STIRPAT模型的节能建筑围护结构能耗分析方法.首先,分析节能建筑围护结构的能耗情况,采用STIRPAT模型从宏观角度模拟对建筑能耗进行模拟,通过eQUEST软件进行微观建筑能耗分析.从人口、城镇化、建筑面积、消费水平、第三产业的发展五种建筑能耗的主要宏观影响因素和门窗、墙体、屋顶三种微观影响建筑围护结构能耗因素展开分析,通过回归分析法和反映系数法对宏观因素和微观因素实行计算.结果 表明,节能建筑能耗的宏观影响因素以消费水平指数和人均建筑面积为主,第三产业发展水平、城镇化率和人口总数为辅;节能建筑围护结构中窗传热系数最高,墙体传热系数略低,屋顶传热系数最低,节能建筑围护结构能耗大小排序为窗＞墙体＞屋顶.     

新建建筑不同设置围护结构的热质耦合传递对建筑负荷的影响Ⅱ:冬季湿负荷

传统建筑室内湿负荷的计算大多不考虑围护结构内表面的散湿量,而围护结构内表面的散湿量尤其是新建节能建筑对室内湿负荷的影响是很大的。以哈尔滨地区为例,分析了严寒地区典型新建建筑不同设置的多层围护结构在最初四年内热质耦合传递对模拟房间湿负荷的影响,并与文献[5]的模拟结果进行对比。分析结果表明：新建建筑围护结构内表面粘贴墙纸或降低围护结构主体砌块的初始含湿量能够降低模拟房间冬季湿负荷;而保温层内侧隔汽层以及围护结构外表面釉面砖的使用都会增加新建建筑的模拟房间冬季湿负荷,但若延后釉面砖的粘贴时间会有所好转。     

建筑墙体动态传热计算模型研究

根据电路原理和克希荷夫电流定律,提出了一种计算建筑多层墙体的非稳定传热的热流网络模型3R2C仿真模型,该模型可用于模拟和分析多层围护结构非稳定传热。该方法简单,易于编程实现,且比较和验证的结果表明这种模型在计算建筑围护结构非稳定传热时速度快、精度高、结果准确可靠。     

基于图像处理的建筑群室外热环境数学模型及实例分析

针对早期规划阶段的建筑群室外热环境问题,为建筑群空气流动建立了区域网络流动模型(即用建筑、地面等围成不同的流动区域),并通过各个流动区域的开口将这些流动区域连接起来构成网络模型;同时对建筑群中的建筑和地面建立了辐射、导热数学模型.在整体的数学模型中考虑了太阳直射、太阳散射、反射辐射、长波辐射、空气流动换热、建筑的外围护结构传热、地面传热等因素,分别以建筑、地面、空气为对象,建立热平衡方程进行耦合求解.同时,应用数字图像技术,实现了数字图像与建筑群室外热环境数学模型的结合.并通过实体建筑群的模拟分析和实测比较,验证了该模型的合理性.     

新建建筑围护结构的传热系数变化研究

对严寒地区新建建筑围护结构的干燥过程进行了模拟,建立了不同干燥时期的热质耦合传递质能平衡方程,确立了围护结构各层多孔介质材料导热系数随含湿量和结冰量的变化关系,对围护结构传热系数的变化情况进行了模拟,分析了新建建筑传热系数随着围护结构不断干燥的逐年变化规律。模拟结果表明:在严寒地区,新建建筑围护结构冬季的传热系数由于内部含湿量结冰要高于夏季围护结构传热系数,但围护结构冬季传热系数逐年下降,尤其前三年下降较明显。     

既有建筑的围护结构节能改造分析

以某办公建筑和住宅楼为模型,对其进行围护结构节能改造分析.通过计算比较改造前后室内负荷的变化,发现节能效果相当显著,证明在我国既有建筑围护结构节能改造存在相当大的潜力.     

基于室内均匀辐射场的西北农村节能建筑热工设计

针对西北气候条件和当地农村建筑特点,利用室外综合温度作为围护结构热工分析的边界条件,提出了基于室内均匀辐射场的农村节能建筑围护结构热工设计方法,并对利用该方法与常规方法设计的围护结构内表面温度进行了对比分析.结果表明,该方法能有效降低室内不对称辐射温度差异,并能作为同类地区农村建筑围护结构设计的理论参考.     

酒店建筑围护结构设计与能源管理

本文论述了酒店建筑围护结构的节能原理，建筑围护结构设计与建筑节能的若干重要问题及墙体、门窗、屋顶围护结构的节能技术与措施。     

含石蜡层玻璃围护结构的一维传热分析

考虑太阳能辐射传热和石蜡材料的相变特性,建立了含石蜡层玻璃围护结构的导热、相变和辐射耦合传热模型,利用布格尔定律跟踪太阳能辐射传输,采用控制容积法离散传热方程,分析了辐射传热对含石蜡材料玻璃围护结构的热影响,并探讨了石蜡吸收系数和折射率对含石蜡层玻璃围护结构的传热影响。研究结果表明:辐射对含石蜡层玻璃围护结构传热过程影响较大;石蜡的吸收系数和折射率对含石蜡层玻璃围护结构内部温度、热流以及透光率的影响显著。结论为含石蜡层玻璃围护结构的设计提供了理论参考。     

Evaluating rammed earth walls: a case study

The following research has been undertaken as a response to the recent controversy regarding the suitability of rammed earth wall construction as an effective building envelope in regard to its thermal performance. The R-value for rammed earth walls is low hence they might be expected to conduct heat into a building during summer. However the large mass of these walls and the associated thermal lag in heat transfer from outside to inside may result in the walls performing satisfactorily in a building which is only occupied during working hours. Internal rammed earth walls may act as moderators of large diurnal temperature swings helping to produce an even comfortable temperature within a building. Empirical (in situ) measurements of temperature and heat flux were taken on the walls of an existing rammed earth office building in New South Wales, Australia during the summer. An analysis was performed which established a methodology to measure the heat flow associated with the walls, floor, ceiling, windows and infiltration for one office during occupied hours and the net energy transferred between the office and these elements was established. During this time the earth walls performed well. External walls were found to transmit comparatively little heat to the office and the internal walls absorbed heat during this time. Diffuse sky radiation transmitted by the window and infiltration are both likely to be important factors in the summer heat load.     

Thermal and energy analysis of a Chinese kang

About 67 million Chinese kangs are still used by about 175 million people in China today. The kang utilizes biomass burning for space heating and hence reduces the use of commercial energy. However, the existing design of kangs is largely based on the accumulated experience of craftsmen, for lack of scientific studies and engineering design guidelines. Poor construction of kangs also leads to serious indoor air pollution. In this paper, a macroscopic smoke flow and heat transfer model of an elevated kang is integrated in a widely-used building energy analysis software in China-DeST, and the integrated software can be used for the thermal performance analysis of kang-integrated houses. A typical house with kangs in various villages of northern China is chosen as a case study. The annual performance of the kang under different insulations of building envelope and climatic conditions are discussed. Based on the simulation results, it is found that the thermal comfort requirement of the outside surface of the upper kang plate can be met by a proper construction of the kang and selection of the appropriate firing pattern. The better the insulation of the building envelope is or the better the room air tightness is, the greater the indoor air temperature rise and the greater the building heating load contribution of the kang. In the eight selected cities in northern China, the use of kang can meet 50%–80% of the house heating load.     

Comparative effects of building envelope improvements and occupant behavioural changes on the exergy consumption for heating and cooling

Much focus is put on measures to improve the building envelope system performance to reduce the impact of the building sector on the global environmental degradation. This paper compares the potential of building envelope improvements to those of a change in the occupant's behavioural pattern. Three cases of improvements together with a base case were analysed using exergy analysis, because the exergy concept is useful to understand the underlying processes and the necessary adjustments to the calculation of the heat-pump system. The assumptions for the occupant behaviour were set up based on our field measurements conducted in a dormitory building and the calculation was for steady-state conditions. It was found that the potential of occupant behavioural changes for the reduction in exergy consumption is more affected by the outdoor temperature compared to building envelope improvements. The influence of occupant behaviour was highly significant (more than 90% decrease of exergy consumption) when the temperature difference between indoors and outdoors is small, which is the case for long periods in regions with moderate temperatures during summer and/or winter. Nevertheless, both measures combined lead to a reduction from 76% up to 95% depending on the outside conditions and should be the final goal.     

Integrated analysis of whole building heat,air and moisture transfer

There is a continuous dynamic heat, air and moisture (HAM) interaction between the indoor environment, building envelope and mechanical systems. In spite of these interdependences, the current indoor, building envelope and energy analysis tools are used independently. In this paper a holistic HAM model that integrates building envelope enclosures, indoor environment, HVAC systems, and indoor heat and moisture generation mechanisms, and solves simultaneously for the respective design parameters is developed. The model is benchmarked with internationally published test cases that require simultaneous prediction of indoor environmental conditions, building envelope moisture performance and energy efficiency of a building.     

建筑物冬季空气渗透耗热量分析

对冬季建筑物外围护门窗结构冷风渗透耗热量进行理论分析,考虑通过空气渗透和侵入造成的潜热热负荷,并对显热热负荷和潜热热负荷进行逐时计算,将结果进行比较分析。结果表明在冬季供暖空调标准工况下,24h周期内空气渗透造成的潜热热负荷约是其相应显热热负荷的8%。对于高层建筑以及室内温湿度要求较高的建筑,进行采暖负荷设计时有必要考虑这部分潜热负荷。     

A proposal for “correction values” for winter outdoor design temperatures

This study aims to find a correlation between winter outdoor design temperature (WDT) and mass of the building envelope. The daily variations of the inside surface temperatures and heat fluxes of the walls under various climatic conditions and different wall constructions have been calculated by a computer program based on the response factor technique, which uses variable outside air temperature and solar radiation and constant inside air temperature values as input climatic data. The analysis of the relation between mass of the walls and inside surface heat fluxes resulted with the correction values for winter design temperature (WDTCV) depending on the mass of the wall and on the direction of facades for different climatic zones.     

温控下被动式太阳房辅助热源量的动态分析

减少对辅助热源的依赖是太阳能建筑设计的一个重要目标,利用建筑自身的集热蓄热能力,可以减少辅助热源量.研究了根据一维热网络模型、温控下辅助热源量的计算公式及热平衡方程,计算不同辅助热源的控制常数以及设定温度下室内温度和辅助热源量的变化;分析了不同的热源控制常数取值和设定温度对室内温度和辅助热源量的影响;讨论了设定温度对墙体蓄热利用的影响.     

Experimental and numerical validation of hygrothermal transfer in brick wall

In this paper, a mathematical model dealing with a coupled heat, air, and moisture transfer in a building envelope was developed. Based on the three-following driving potential: vapor pressure, dry air pressure, and temperature, an application on a hygrothermal behavior of a real wall was carried out for different climatic conditions. For this purpose, a characterization of the heat and moisture properties of the materials constituting the wall made with red brick and cement mortar was carried out in the laboratory. This was used to evaluate experimentally the input parameters of the model as a function of relative humidity. To validate the numerical model, an experimental platform was improved. The wall was set up in a double-climatic chamber with different boundary conditions, and then the temperature and humidity evolutions were recorded using several sensors within the wall thickness. The results have highlighted a good agreement between numerical simulation results and experimental ones.     

锅炉省煤器灰污沉积监测模型

从对流换热理论出发,推导出灰污沉积监测的数学模型,通过对简单实用的温度和压差等检测量,直接计算出灰污热阻值,以监测受热面灰污沉积状况.该模型避免了测量热流密度、灰污界面温度和流体速度等物理量.进行了所有工况的灰污热阻正交实验,结果表明该监测模型是合理可靠的.表1参9     

The importance of a storage tank in the brine cycle of an absorber roof-assisted heat pump

A dynamical model to calculate the performance of an absorber roof-assisted heat pump is developed. The model is applied to a specific example, a normal residence building in Berlin. The heat pump is layed out to meet the heat demand at 0°C outside temperature. The auxiliary heat is provided by a conventional backup system. Conditions of insolation and outdoor temperature are derived from real weather data and simulated in their dynamical behaviour. The analysis investigates how the variation of the storage tank volume and the lower limiting COP is reflected in the annual cost savings.