反射隔热涂料在长沙地区的适用性研究

近年来,外墙反射隔热涂料得到了越来越广泛的应用。为了探究其在长沙地区的适用性及节能效果,采取实测和模拟的方法,通过对涂刷反射涂料、保温砂浆的测试房以及普通房的温度对比,验证了反射涂料在夏季起隔热作用而对冬季保温不利;运用EnergyPlus程序对表面吸收系数不同的两栋建筑进行温度和能耗对比,发现夏季反射涂料隔热效果明显,尤其是东、西外墙及屋面;反射涂料可显著降低夏季空调能耗,冬季能耗小幅增加,全年总能耗下降7.8%。     

建筑用反射隔热涂料的研制

目前,反射隔热涂料的生产通常是采用钛白粉、PU空心微珠、空心微珠、陶瓷微珠、膨胀珍珠岩等配合少量的纳米反射隔热功能材料来达到反射隔热功能,但其存在涂膜粗糙、装饰性差的缺点,同时降低了涂膜的耐沾污性。本项研究主要结合钛白粉与纳米反射隔热功能材料的特点,配制出具有良好反射、隔热效果的高耐候型反射隔热涂料,通过模拟实验、光学指标的测试,均证明研制的反射隔热涂料的反射隔热效果显著,具有广泛的实际应用价值。     

微珠掺量对热反射隔热涂料隔热性能的影响

通过模拟试验,研究分析了不同空心玻璃微珠掺量对热反射隔热涂料隔热性能的影响,试验结果表明,未掺微珠的涂料与微珠掺量为15%的涂料相比,隔热效果相差4℃左右。     

反射隔热涂料在深圳地区住宅中的应用效果分析

以深圳地区典型住宅为例,对反射隔热涂料在屋顶及外墙的隔热及节能效果进行了模拟分析。结果表明,反射隔热涂料的太阳光反射比越大,其隔热及节能效果越明显。与外保温方式相比,外墙外表面涂刷反射隔热涂料同样能起到较佳的节能效果,在深圳地区具有推广价值。     

基于热平衡理论的隔热涂料夏季节能效果模拟与分析

根据热平衡理论建立了围护结构稳态传热模型,计算隔热涂料对围护结构传热的影响。结果表明,夏季反射隔热涂料在白天降低围护结构传热量的效果更优异,夜晚节能效果会有所降低;辐射型隔热涂料能够在昼夜稳定地降低围护结构传热量。此外,对北方地区应用隔热涂料后室内温度和空调能耗情况进行了动态模拟。建筑模型能耗模拟表明,应用反射型隔热涂料(以反射比0.7为例)后,夏季室内温度与对照组相比降低0.47～0.69℃,整个夏季空调能耗降低17.60%;应用辐射型隔热涂料(以发射率0.9为例)后,夏季建筑室内温度降低0.45～0.51℃,整个夏季空调能耗降低14.60%。     

反射隔热真石漆的制备及其性能研究

在普通真石漆配方的基础上,通过添加高反射性颜填料及陶瓷微珠,制备了反射隔热真石漆,并对其反射性能、隔热性能及涂料基本性能进行了测试。结果表明,所制备反射隔热真石漆的反射性能和隔热性能均优于同色系的普通真石漆,且涂料的基本性能均能优于JG/T 24—2018《合成树脂乳液砂壁状建筑涂料》要求。     

色浆对热反射隔热涂料热反射性能的影响

通过向白色热反射隔热涂料中添加不同颜色的色浆,然后测试250～2500nm范围内光谱反射性能.比较研究了添加不同浓度的铁红、铁黄、酞青蓝、酞青绿色浆后,热反射隔热涂料近红外区段热反射性能的变化规律.     

建筑反射隔热涂料隔热机理及性能试验研究

建筑反射隔热涂料是一种新的功能型建筑涂料,从光学、传热学、建筑学的基本理论出发,分析了建筑反射隔热涂料的隔热机理,并对今后的研究应用提出了建议。对白色、米黄色、棕色、深咖啡色、红色5种不同颜色体系反射隔热涂料产品的太阳光反射比、近红外反射比、半球发射率性能进行了研究,分析了采用传热系数试验方法对比基层墙体和涂刷反射隔热涂料的热阻变化。结果表明:建筑反射隔热涂料颜色明度值是决定太阳辐射热量反射效果的重要指标,半球发射率与涂料表面颜色关系不大,一般为0.8~0.9,涂刷反射隔热涂料的墙体热阻值增加了0.003 m2·K/W。     

反射隔热涂料-保温胶泥外墙保温系统性能研究

对反射隔热涂料-保温胶泥外墙保温系统进行材料及系统的试验.结果表明,保温胶泥具有比较良好的物理、热工性能及施工性能.保温胶泥与反射隔热涂料组成的外墙保温系统,经外墙隔热温差及耐候性测试,表现出具有较好的隔热及耐久性能.     

反射隔热涂料半球发射率的检测方法及设备介绍

根据反射隔热涂料半球发射率检测的三种常见方法,总结反射隔热涂料标准中的技术指标。介绍测试半球发射率的便携式辐射率仪法的设备原理及组成。比对稳态量热计法和便携式辐射率仪法测得的反射隔热涂料的半球发射率的结果。     

关于热感觉和热舒适与热适应性的讨论

系统地论述了人体热舒适研究的发展过程,讨论了热感觉、热舒适及热适应的定义,并分析了热感觉与热舒适的差异及与热适应性的关系,得出了人们对同一热环境有不同的热感觉及热舒适性,主要是由于人体的适应性产生的。     

Adaptive thermal comfort and sustainable thermal standards for buildings

The origin and development of the adaptive approach to thermal comfort is explained. A number of recent developments in the application of the theory are considered and the origin of the differences between adaptive thermal comfort and the ‘rational’ indices is explored. The application of the adaptive approach to thermal comfort standards is considered and recommendations made as to the best comfort temperature, the range of comfortable environments and the maximum rate of change of indoor temperature. The application of criteria of sustainability to thermal standards for buildings is also considered.     

岩土热物性热响应测试的试验研究

通过测试装置测定出测试孔输入功率、环路平均温度,采用线热源模型对现场测试数据进行推导分析,计算出测试孔岩土导热系数,该数值对在当地以及周边地区进行土壤源热泵系统设计具有重要的参考价值。     

聚氨酯与聚苯保温系统比较

PUF（聚氨脂泡沫）、EPS、XPS都是性能优越的保温材料，其保温体系孰优孰劣，众说纷纭。笔者结合多年PUF保温工程实践，对三者作综合比较，以供业内同仁参考。     

绝热材料低温导热系数的测试

采用防护热平板法进行绝热材料低温导热系数测试,测试实践解决了4个关键试验条件：测试堆的制冷、冷却水套及其管路中残留水的清除、冷凝水的去除和隔热、外防护套的配置。通过对国家标准参比低温导热系数的测试,结果表明：采用防护热平板法测试结果得出的导热系数方程与《绝热材料导热系数参比板》国家标准样品证书提供的导热系数方程吻合得很好,并认为将此方程外推至－60－0℃的数据可以作为校准导热仪的参考值。     

混凝土热传导与热应力的细观特性及热开裂过程研究

通过对混凝土热传导与热应力细观特性的分析,探讨细观非均匀性对混凝土热学和力学性能的影响作用。计算结果表明:细观非均匀特性对混凝土导热性能的影响并不明显,但对其力学性能的影响作用却不能忽视;骨料颗粒对混凝土的热学和力学性能都有显著的影响作用。温度梯度和热膨胀不匹配共同作用所产生的温度应力极容易导致混凝土开裂,其中温度梯度引起的混凝土开裂过程与热传导系数密切相关。通过对厚壁筒混凝土试样在孔内温度升高情况下裂纹萌生和扩展过程的数值模拟研究,从机理上揭示试验观测的四个裂纹发展阶段。研究结果表明裂缝扩展的局部化效应是主裂纹形成的根本原因。     

Uniformity of stratum‐ventilated thermal environment and thermal sensation

Three human test series were conducted to evaluate the uniformity of the thermal environments in a stratum‐ventilated chamber with dimensions of 8.8 m (L) × 5.1 m (W) × 2.4 m (H). In all, nineteen conditions were generated by adjusting the room temperature, supply airflow rate, and supply terminal type. An air diffuser performance index (ADPI) of at least 80% was achieved for most cases. This result shows that the air velocity and temperature in the occupied zone are reasonably uniform. Subjective assessments using the ASHRAE 7‐point scale indicate that the thermal sensations of the subjects in stratum ventilation are also uniform. This study examines the applicability of the predicted mean vote (PMV) model for evaluating stratum ventilation. When compared to the actual mean thermal sensation votes (ATS), the PMV values are acceptable. The PMV results at a height of 1.1 m above the floor show better agreement with the ATS than at a height of 0.1 m.     

Real-time predictive supervisory operation of building thermal systems with thermal mass

The real-time predictive dynamic operation of building thermal systems is explored in this paper. A systematic methodology is described for predictive supervisory operation. The focus of this study is on the development of an operation supervisor that can determine optimal operation strategies for building thermal processes, and its application to a floor heating system in a passive solar room with thermal mass. An optimal model associated with a number of practical operation constraints is formulated, and an approach that combines dynamic programming and on-line simulation is developed, to efficiently solve the problem in real-time. Simulations for the minimisation of energy consumption and operating cost, with different operation schedules under various weather conditions, are performed. Results show that the techniques are computationally efficient and that the predictive supervisory operation of floor heating systems may lead to significant savings in energy consumption and operating cost.     

Estimation of thermal conductivity of cemented sands using thermal network models

Effective thermal conductivity of soils can be enhanced to achieve higher efficiencies in the operation of shallow geothermal systems.Soil cementation is a ground improvement technique that can increase the interparticle contact area,leading to a high effective thermal conductivity.However,cementation may occur at different locations in the soil matrix,i.e.interparticle contacts,evenly or unevenly around particles,in the pore space or a combination of these.The topology of cementation at the particle scale and its influence on soil response have not been studied in detail to date.Additionally,soils are made of particles with different shapes,but the impact of particle shape on the cementation and the resulting change of effective thermal conductivity require further research.In this work,three kinds of sands with different particle shapes were selected and cementation was formed either evenly around the particles,or along the direction parallel or perpendicular to that of heat transfer.The effective thermal conductivity of each sample was computed using a thermal conductance network model.Results show that dry sand with more irregular particle shape and cemented along the heat transfer direction will lead to a more efficient thermal enhancement of the soil,i.e.a comparatively higher soil effective thermal conductivity.     

热力管道的保温与防腐施工技术研究

热力管道保温与防腐施工质量会直接影响到整个热力系统的质量,同时也会对人们的正常生产与生活造成一定影响。分析了热力管道保温以及防腐施工的相关要求,阐述了热力管道保温与防腐施工技术要点,希望能够为进一步提升热力管道保温与防腐施工质量提供有价值的参考。