【作者】 胡磊；

【导师】 陈友明； 周涛；

【作者基本信息】 湖南大学 ， 建筑与土木工程（专业学位）， 2018， 硕士

【摘要】 围护结构是建筑能源消耗最大的部位,而玻璃外窗作为围护结构最主要的组.成部分,随着科学的进步,新型围护结构也越来越多,针对玻璃系统保温隔热材料的研究也越来越多。纳米多孔Si02气凝胶因具有高孔隙率、低热导率、低折射率以及高透过率等优良特性,使气凝胶玻璃在建筑节能领域获得越来越高的重视。本文研究对象为颗粒气凝胶玻璃:将颗粒状气凝胶材料密实填充于双层玻璃的空隙中所制成的玻璃系统。目前气凝胶玻璃理论分析多以K-SC模型模拟,其能近似计算气凝胶的光热特性参数,但是一来采用特定入射条件下的气凝胶玻璃太阳能得热系数、遮阳系数,未考虑玻璃热工性能随室外气象条件的动态变化,其无法准确计算不同入射角情况下室内太阳得热;二来但由于气凝胶结构的特殊性使得气凝胶玻璃某些参数难以确定,现有的能耗模拟软件还无法准确计算气凝胶玻璃系统光,热和辐射传输过程。因此,对气凝胶玻璃光热性能进行动态模拟分析是十分必要的。本文通过三个相互关联的数学模型来模拟计算气凝胶玻璃光热传递。太阳辐射计算模型,通过该数学模型可以得到不同时刻太阳能到达玻璃系统表面的太阳辐射以及太阳光入射角;气凝胶玻璃光学模型,通过该数学模型可以得到气凝胶玻璃系统不同时刻下各层介质吸收量和总透过量,前面两个模型为最后模型提供了计算基础;传热模型,通过最后的动态传热模型得到玻璃系统各个节点逐时温度值和室内逐时得热量。采用模拟出来的温度、太阳辐射透过量等数据与实验采集的数据进行对比分析,验证了模型的正确性。采用所建立的模型在VC++平台上模拟了长沙地区不同工况、不同朝向气凝胶玻璃光热传递过程,并对气凝胶玻璃系统光学计算模型、温度节点等进行了简化。光学计算简化方面,在夏季晴天总太阳辐射值特别大的时候,其误差是比较大的,不过最大相对误差不超过15%,而对于总太阳辐射值比较小或是阴天工况,简化计算室内得热与精确模型相比,误差比较小甚至没有误差;节点简化方面,本文分析出把气凝胶玻璃中间层多个传热节点简化为一个中心节点是完全可行的,无论是晴天工况还是阴天工况,一天的负荷计算整体相对误差不会超过1%;对于气凝胶材料的消光系数,若把气凝胶材料的消光系数简化为一个定值处理,一天的负荷计算整体相对误差都低于5%。最后,把所建立的计算模型编译成源代码,进行FMU模块的开发,能够方便DeST主程序对FMU的调用计算。更多还原

【Abstract】 The building envelop structure is the most important part of building energy consumption,while the glass window is the most important part of the building envelop structure.With the progress of science,more and more new energy saving envelopes are also made.Nano-porous silica aerogel have attracted increasing attention due to their high porosity,low thermal conductivity,low refractive index,and high transmittance.The object of this paper is particle aerogel glass:a glass system made by densely filling granular aerogel material in the interstices of double glass.At present,theoretical analysis of aerogel glass is mostly simulated by K-SC model,which can approximate the photothermal characteristics of aerogels.However,at first,the solar heat gain coefficient and shading coefficient of aerogel glass under specific incident conditions have not taken into account the dynamic changes of glass thermal performance with outdoor weather conditions,and it cannot accurately calculate the solar heat gain at different incident angles.Second,due to the special nature of the aerogel structure,certain parameters of the aerogel glass are difficult to determine,and the existing energy simulation software cannot accurately calculate the light,heat,and radiation transmission processes of the aerogel glass system.Therefore,it is very necessary to carry out dynamic simulation analysis of the photothermal properties of aerogel glass.This paper simulates the aerogel glass heat transfer through three interrelated mathematical models.The solar radiation calculation model can be used to obtain solar radiation and solar incident angles of solar energy reaching the surface of the glass system at different moments.The aerogel glass optical model can be used to obtain various layers of the aerogel glass system at different times through the mathematical model.The medium absorption and total transmission,the first two models provide the basis for the calculation of the final model;heat transfer model,through the final dynamic heat transfer model to obtain the temperature value of each node of the glass system and the hourly heat in the room.Using the simulated temperature and solar radiation transmission data and the data collected from the experiment to compare and analyze,the correctness of the model was verified.The established model was used to simulate the photothermal transfer process of aerogel glass under different working conditions and different orientations on the VC++ platform.The optical calculation model and temperature nodes of the aerogel glass system were simplified.Simplification of optical calculations,when the total solar radiation is particularly high in summer sunny days,the error is relatively large,but the maximum relative error does not exceed 15%,and for the total solar radiation is relatively small or cloudy conditions,simplified calculations Compared with the accurate model,the indoor heat gain is relatively small and there is no error node simplification;this paper analyzes that simplifying multiple heat transfer nodes in the middle layer of aerogel glass into a central node is completely feasible,whether it is sunny conditions or In cloudy conditions,the overall relative error of one day’s load calculation will not exceed 1%;for the extinction coefficient of aerogel material,if the extinction coefficient of the aerogel material is reduced to a fixed value,the overall relative error of the daily load calculation Both are less than 6%.Finally,compiling the established calculation model into source code and developing the FMU module,it is convenient for the DeST main program to calculate the call to FMU.更多还原