与建筑一体化太阳能双效集热器系统在被动采暖工作模式下的热特性研究

针对该新型系统的被动采暖工作模式,基于热箱实验平台,实验研究分析系统该工作模式下运行的热特性情况。研究结果表明,系统在冬季被动采暖工作模式下,房间室内空气温度存在明显的温度分层现象,且温度分层造成的室内上下部的温差与投射在系统集热模块表面的太阳辐射强度存在某种线性关系。此外,实验结果还显示,系统在冬季被动采暖工作模式下依靠热虹吸作用可使集热模块上风口的空气温度加热至50℃以上。     

青海省农牧区低能耗农房室内热环境测试研究

对青海省贵德县一新建农房室内热环境进行测试,分析研究各项太阳能采暖技术在其中的节能特性,对比黑箱模式与主被动结合模式2种采暖模式下室内热环境的差异。结果显示,黑箱模式下,良好的外围护结构能够使室内温度保持基本恒定;主被动结合模式下,南向房间室内外平均温差高于17.34℃,室内重点区域温度基本达到热舒适要求,系统常规能源替代量为4.14千克标准煤。     

一种主、被动结合的太阳能空气采暖模拟研究

主、被动结合的太阳能双效集热器空气采暖系统,可同时解决南向房间和北向房间的供暖问题。借助TRNSYS仿真平台,编写双效集热器的嵌入模块,对应用在太阳能示范建筑上的主、被动式双效集热器空气采暖进行模拟研究。模拟结果显示在合肥地区,木质结构的示范房只需白天供暖情况下,整个采暖期的太阳能保证率为38%,而同样条件下在拉萨和上海地区,太阳能保证率分别达到77%和58%;若示范建筑采用有蓄热能力的混凝土砖墙结构,在拉萨地区全天供暖条件下太阳能保证率达到64%;晴朗天气,南向房间和北向房间白天均可达到20℃舒适性温度。同时讨论集热器倾角、出口温度、集热面积等对主动式空气采暖太阳能保证率的影响。     

太阳能散热器采暖与热水供应技术实验研究

通过太阳能采暖与热水供应系统在夏热冬冷地区的实验,测试了系统采暖及提供生活热水时,太阳能集热系统、采暖系统、辅助热源等部分的相关数据,并在实验中分别对采暖房间与非采暖房间的室内温度进行了测试。通过实验数据分析了太阳能采暖与热水供应系统在夏热冬冷地区使用应考虑的问题,并给出系统设计及运行过程中提高系统性能的有关建议,为有关设计提供参考。     

复合太阳能炕系统运行模式的实验研究

提出一种新型复合太阳能炕系统,该系统由提供被动采暖的太阳能空气集热器和提供主动采暖的太阳能炕系统组成。系统的运行模式是影响室内热环境的重要因素,为寻求最佳的运行模式,在3种运行模式下对系统进行实验测试。结果发现:当系统以晚上模式或下午模式运行时,运行过程中炕体所吸收的热量在之后的放热过程中无法充分释放,且炕面和空气温度的波幅较大;当系统以傍晚模式运行时,炕体能够充分发挥其蓄热优势,使炕面和空气温度的变化相对平缓。     

太阳能辅助CO2热泵供热系统的试验与优化研究

提出一种用于住宅采暖和全年提供生活热水的太阳能辅助CO2热泵供热系统,并将该系统运用于上海地区一座90 m2的示范住宅。其中,真空管集热器阵列的面积为40 m2,CO2热泵压缩机的额定功率为2 k W。通过冬季试验对系统进行性能测试。并在此基础上,运用TRNSYS软件建立系统模型,对包括蓄热水箱容积和工作水箱容积等系统的结构参数进行优化分析。结果表明:在环境温度为4.8℃、机组进出口水温37.9℃和48.6℃的实验工况下,CO2热泵机组的COP可达2.63,CO2热泵单独供热模式的系统性能系数COPS可达2.24;在该文实验工况下,太阳能采暖模式的系统性能系数COPS为14.53;当蓄热水箱和工作水箱的容积分别为0.9 m3和0.7 m3时,系统在整个采暖季的耗电量最小且太阳能的保证率达到65.7%。     

基于TRNSYS的CPC集热器太阳能热水系统的模拟分析

通过TRNSYS软件搭建了复合抛物面聚光器(CPC)集热器太阳能热水系统模型,对广州地区某小型别墅的太阳能热水系统进行了设计,并观察系统在1年(8760 h)中的运行情况。选取了系统在4个典型日的运行情况进行分析,得到了CPC集热器在春分日和冬至日的最高出口温度分别为67.5℃和68.2℃,在夏至日和秋分日的最高出口温度分别为85.7℃和83.3℃。CPC集热器的集热效率随进口流量的增大而增大,随进口温度的下降而升高;经测试,CPC集热器的最佳安装倾角为22°。对CPC集热器和平板集热器的集热性能进行比较后发现,二者的集热功率基本均随太阳辐照度的增加而增加,在冬至日12:00~15:00这个时段,CPC集热器的集热功率是平板集热器的1.5倍。     

太阳能辅热相变蓄能火炕供暖系统实验研究

将相变蓄能和毛细管网型太阳能采暖两种技术同时运用于火炕供暖上,通过实验研究相变蓄能材料和太阳能毛细管网低温热水联合辅助供暖时对室内温度和舒适性的影响,得出普通房间炕头、炕中、炕尾的平均温度分别为65.70、43.28、39.82℃,温差大于20℃,而采用该系统的房间炕头、炕中、炕尾的平均温度分别为40.96、39.06、37.52℃,温差最大仅为3℃;夜间炕面温度下降阶段,铺有相变材料的炕面温度下降缓慢,在00:00~07:00之间均高于普通火炕炕面温度,优势明显。新模式下的房间白天室内平均温度比普通房间高14.31℃,夜间比普通房间高7.21℃,可改善农居室内及炕面的热舒适性。     

相变蓄热型光伏集热墙体系统的冬季实验研究

以可对比热箱为实验平台,构建相变蓄热型光伏集热(PV-PCM-Trombe)墙体实验系统。通过冬季工况测试,实验分析该系统的光电性能和对建筑热环境的影响等特征。研究结果表明:实验间气温始终高于对比间气温和环境温度,且日平均环境温度越高,实验间与对比间和环境温度的温差也越大,表明本系统可在冬季高效利用太阳能很好实现地建筑被动采暖;相变板在白天吸收太阳能蓄热,可使房间在冬季夜间维持更长时间的舒适温度;实验期间系统的平均光电效率约为13.71%,系统工作时其光电效率与开路电压存在强关联特征。     

几种能源系统利用技术与经济现状

太阳能热系统太阳能热系统能为家庭、农业与工业加工提供热水或热空气,用于谷物干燥、制浆、低温食品加工等。其中家庭应用较多的是烧水和炊事。其它还有制淡水和致冷。平板集热器供热温度能达到93℃,而真空管集热器则可达到约177℃。如用温不高,也可直接利用太阳能浅池。平板和真空管集热器已商品化生产,渗透到美国住宅和商业大楼采暖等市场。在以色列、奥大利亚、日本、美国等有几千只热水系统在运行。实践证明,太阳能热水系统与常规的热水系统一     

我国太阳能集热器建筑构件化概念探讨——建筑师的声音

目前太阳能集热器市场逐渐向建筑构件化的方向发展,而相应的理论层面缺乏明确的概念指导,该文针对这一问题,从建筑师的角度探讨太阳能集热器建筑构件化的概念,以期在明确概念的基础上,更好地推进太阳能热水系统与建筑的整合设计。     

Thermal characteristics of a building-integrated dual-function solar collector in water heating mode with natural circulation

As a modified building-integrated solar thermal system, building-integrated dual-function solar collector here proposed is able to provide passive space heating in cold winter, and water heating in warm seasons. In this study, evaluations were made on this modified collector system for the warm period operation under the water heating mode with natural circulation of flow. A dynamic numerical model has been developed and validated by experimental data. Based on practical air-conditioned room design conditions, numerical analysis was performed to study the water heating performance, as well as to compare the solar transmission through building facade in different seasons with or without its presence. The results show that when working in the water heating mode, the system performs well in providing services hot water in the warm seasons without bringing in summer overheating problem.     

Computational evaluation of solar heating systems using concrete solar collectors

This paper uses the F-chart technique to evaluate three types of solar heating systems, namely; space solar heating and domestic hot water system (SHDHW), domestic hot water system (DHW) and solar swimming pool heating system (SPHS), using three types of concrete solar collectors, models A, B, and C, and one conventional metallic solar collector.

The economical analysis of SHDHW system revealed that the concrete collectors provided about 49 and 63% of the annual load when the collecting area of the solar panel increased from 55 to 88 M² (25 to 40% of the building roof area). The corresponding solar contributions when conventional metallic collectors were used are 41 and 53%, respectively. This represents an improvement of the annual solar fraction of about 19% when concrete collectors are used instead of the metallic collectors.

It was found that solar heating systems with concrete solar collector models gave higher solar fractions and total life cycle savings than the conventional solar metallic collector.     

Energy and economic analysis of an integrated solar absorption cooling and heating system in different building types and climates

The use of solar energy in buildings is an important contribution for the reduction of fossil fuel consumption and harmful emissions to the environment. Solar thermal cooling systems are still in their infancy regarding practical applications, although the technology is sufficiently developed for a number of years. In many cases, their application has been conditioned by the lack of integration between cooling and heating systems. This study aims to evaluate the potential of integrated solar absorption cooling and heating systems for building applications. The TRNSYS software tool was used as a basis for assessment. Different building types were considered: residential, office and hotel. The TRNSYS models are able to run for a whole year (365 days), according to control rules (self-deciding whether to operate in heating or cooling modes), and with the possibility of combining cooling, heating and DHW applications. Three different locations and climates were considered: Berlin (Germany), Lisbon (Portugal), and Rome (Italy). Both energy and economic results are presented for all cases. The different local costs for energy (gas, electricity and water) were taken into account. Savings in CO₂ emissions were also assessed. An optimization of solar collector size and other system parameters was also analysed.     

Evaluation of a solar thermal system using building louvre shading devices

External louvres are increasingly used to provide solar protection for building glazed surfaces. The integration of collectors into the external louvres of buildings offers a means of reducing system cost as well as providing architects with more freedom to integrate the technology into their designs. This work concerns the modification of existing louvre designs to integrate a solar collector in the shading device. The evaluation of a thermal solar system for water heating is assessed in this paper. A numerical model for the integrated solar collector was developed for different configurations and the collector efficiency is quantified for each configuration. System thermal performance was obtained for the climatic conditions of Lisbon (Portugal) and Tenerife (Spain). Economic and environmental viability of the system is assessed.     

农村太阳能供暖住宅

以农村住宅进行太阳能供暖模拟试验得出的结论为依据,提出农村太阳能供暖住宅的设计方案:①提高农村住宅的保温隔热性能.降低建筑能耗;②要创新太阳能供暖设备,提高供暖系统的热效率;③实施太阳能与建筑一体化,使住宅热负荷与太阳能集热器的有用热量相匹配,实现农村住宅的主房间室内温度常年保持在16℃～28℃之间波动,居住舒适.     

一种可蓄热太阳能睡床结构及性能分析

介绍了一种兼具蓄热与散热两种状态的太阳能供暖用睡床。该睡床的下部为蓄热水箱，可从太阳能集热板获取热量供给睡床。研究了基于该睡床的供暖系统在北京地区的应用情况，并分析了不同状态下床板上表面的散热量与被褥内的温度。结果表明：在全天散热状态下，典型年供暖季集热器效率为37.7 %，复合型睡床的有效供热量为4 390.2 MJ，太阳能保证率为80.7 %；在白天保温−夜间散热下，集热器效率为33.1 %，复合型睡床的有效供热量为4 441.1 MJ，太阳能保证率为81.8 %。     

Integration of solar air collector with phase change material wall for a heating system

可再生能源的高效利用是降低建筑能耗的有效方法。将相变储能墙与太阳能热风相结合,可改善太阳能热风采暖的不稳定性,从而提高太阳能的利用效率。通过试验和ANSYS模拟软件对复合系统的分析,确定相变储能墙体的储热特性和合理用量,研究复合采暖系统的室温变化和传热规律,分析相变储能墙对采暖系统的贡献率。结果表明：与未采暖房间相比,复合采暖系统可以使室内平均温度提高7~15℃,该复合采暖系统具有一定的应用前景;当太阳能空气集热器的送风口温度在37~77℃时,相变材料能够充分利用,相变墙整体的相变比例约为40%,从线性回归比例看,复合采暖效果要比太阳能热风采暖效果好。     

Integrated solar heating systems: From initial sizing procedure to dynamic simulation

The sizing of the solar installation of an individual dwelling is a problem which can be solved in many ways. The approach described in this paper is a simplified procedure of considerable interest. It requires only a small quantity of data and can be computed in a short time. The performance of this procedure was evaluated by a more complex sizing method based on detailed simulation. The simplified procedure was applied to the case of an individual dwelling using a solar collector field to produce domestic hot water and space heating. The building and the solar installation have then been modelled with the software TRNSYS 16 and their behaviour was simulated during a whole year. The results obtained are particularly close to the ones expected by the simplified sizing procedure.     

A general chart for sizing the collectors of solar heating systems

A general chart is developed for calculating the collector area required to provide a prescribed value of the annual load fraction for solar heating systems. The relationship between collector area and annual load fraction can then be easily obtained for specified collector design parameters, load and location. The construction of the chart is based on correlating data generated by the f-chart method. Data of 13 locations in the U.S.A. are considered. The good agreement of the results obtained by the present simple method and the f-chart for both space and combined space/domestic water heating proves that the two methods are almost of the same accuracy. Since the present chart is not location dependent and allows direct comparison of different collectors, it is a very valuable design aid for sizing and selecting solar collectors.