陶瓷太阳板及其应用

陶瓷太阳板以普通瓷土、工业废弃物为原料、制造工艺简单、生产耗能少、成本低、寿命长、效率高;建造的陶瓷太阳能房顶可与原房顶共用结构层、保温层、防水层,结构简单、与建筑一体化、与建筑同寿命,隔热、保温效果优于普通房顶。其应用范围较广,可为建筑物提供热水、取暖、空调,还能用于沙漠太阳能发电、海水淡化、苦咸水淡化等领域。     

一种新型太阳能、风能联合海水淡化装置

淡水资源短缺已成为一个世界性问题,我国也不例外.为了加大淡水供应,一条现实的途径就是充分利用我国丰富的海水资源,以及西北内陆地区的苦咸水(统称海水)进行淡化.提出了一种海水淡化装置,该装置利用温室效应原理和风能致热原理,可充分利用太阳能与风能进行海水淡化.与现有海水淡化装置相比该装置具有利用清洁能源、对环境无污染、适应性强、性价比高等特点.理论计算结果表明,该装置每小时产水量约为普通盘式太阳能海水淡化装置在晴天工作时的2倍.     

适应非稳态电源的集装箱式海水淡化系统设计浅析

我国目前主要的清洁能源为太阳能、风能等,我国南海诸岛太阳能、风能丰富,是海水淡化系统提供电源的好方法。海岛淡水资源匮乏,严重制约了我国国防及能源开采工作,为了大力开发海洋资源亟需实现海岛人员驻扎,所以只有解决了海岛生活供水问题才能实现人员长期驻扎。丰富的太阳能、风能等资源为海水淡化的发展提供了便利的自然条件。反渗透海水淡化(SWRO)是目前我国海水淡化市场最主要的淡化海水技术之一。其中集装箱式海水淡化系统具有设备简单、投运快、投资低等优点。     

节能环保产品——太阳能热水器

随着社会生产力的高速发展,常规能源的加速消耗和环境污染已成为现代社会急待解决的问题。太阳能将成为２１世纪重要的新能源,太阳能的应用极其广泛,在这里仅简单地介绍一下最为普及的太阳能热水器的经济价值与实用价值。人们最早将铁桶刷上黑漆放置在房顶,利用太阳能...     

太阳能利用在约旦

约旦位于亚洲西部,因境内的死海比海平面低392米,故有“世界沉陆”之称。境内五分之四以上的面积是沙漠,太阳能资源极为丰富。政府为了解决本国的能源问题,正在想方设法利用太阳能。约旦太阳能利用的重点是海水淡化,家用热水器,太阳能电话,塑料棚温室及太阳能蒸发池。     

太阳能在海水淡化中的应用

介绍了太阳能与海水淡化技术的几种结合形式,并分析了太阳能在各种海水淡化技术中应用的经济性和适用性;最后指出,随着太阳能集热技术和发电技术的不断发展和海水淡化技术的不断优化,太阳能在海水淡化的应用将更加广泛。     

多级迭盘式太阳能海水淡化装置的性能研究与经济性分析

设计制作了一台多级迭盘式太阳能海水淡化装置。该装置通过折皱底面来强化凝结作用,利用与最下面一级相连的热管式真空管集热器供热,在天气晴朗时能够不需其他动力自动制取淡水,具有操作简单、运行可靠、维护费用低等特点。试验结果表明,该装置利用太阳能制取淡水的性能系数为1.01,是一种较理想的户用太阳能海水淡化装置。文章还对装置寿命期内的经济效益进行了分析。     

三种利用再生能源淡化海水的装置

研究人员试图利用来自太阳和海洋的可再生能源来淡化海水,下面介绍三个实例: 1.法国国家科研中心南希化工科学试验室的戈夫设计了一种在边远干燥地区利用太阳能的盐水淡化装置。这种太阳能蒸馏器的设计简单牢固,任何乡村技工都能维修保养。此装置由太阳能集热器和蒸馏淡化器两     

太阳能光热海水淡化系统应用研究

介绍太阳能光热产蒸汽系统和海水淡化系统,将高温蒸汽和海水淡化装置在集成系统中加以融合,实现一种太阳能光热海水淡化系统,并以风力发电作为辅助系统。文章以全国第一个太阳能光热海水淡化示范项目为例,对该系统进行详细的性能和效果应用分析,在该项目成功产水之后展望太阳能海水淡化今后的发展方向与前景。     

低温多效太阳能海水淡化装置最优集热系统的匹配研究

利用实际天气的太阳辐射值,根据一套低温四效太阳能海水淡化系统稳态实验数据,通过模拟计算,研究分析与该海水淡化系统匹配的太阳能集热系统参数,给出太阳能集热系统集热器面积和储热水箱容量、海水淡化系统启动和暂停温度等参数的最佳取值范围,计算了该装置的年淡水产量,为太阳能海水淡化装置的设计提供一种有效地方法.     

Development of advanced solar assisted drying systems

The Solar Energy Research Group in the Universiti Kebangsaan Malaysia has been set-up more than two decades ago. One of the activities is in the field of solar thermal process, particularly in development of solar assisted drying systems. Solar drying systems technical development can proceed in two directions. Firstly simple, low power, short life, and comparatively low efficiency-drying system. Secondly, the development of high efficiency, high power, long life expensive solar drying system. The group has developed four solar assisted drying systems namely (a) the V-groove solar collector, (b) the double-pass solar collector with integrated storage system, (c) the solar assisted dehumidification system for medicinal herbs and (d) the photovoltaic thermal (PVT) collector system. The common problems associated with the intermittent nature of solar radiation and the low intensities of solar radiation in solar thermal systems can be remedied using these types of solar drying systems. These drying systems have the advantages of heat storage, auxiliary energy source, integrated structure control system and can be use for a wide range of agricultural produce.     

通水除热管板应用于屋面结构中的模型实验研究

针对夏热冬暖地区的屋顶在夏季受太阳辐射强度大的问题,开发一种新型通水除热管板,将该通水除热管板应用于屋面结构中,构成新型通水除热屋面,可以有效改善夏热冬暖地区顶层屋面的热工性能,在间歇空调状况下,同时达到节能和舒适的目的。通过搭建模型实验台进行模型实验来研究通水除热屋面的隔热性能,得出主要结论如下:将铝制通水除热管板埋入屋顶找坡层,在17:00左右通水,此工况下对屋顶内表面有一定的降温效果,阻止晚间屋顶内表面温度的升高,降低了晚间空调的冷负荷,对夏热冬暖地区居住建筑有着重要的应用价值。     

The multiple layer solar collector

The Multiple Layer Solar Collector is a proposed design in which the working liquid passes through several successive transparent layers. It has low reflection losses and operates in a once-through mode thereby ensuring that the outer layer is near ambient temperature.A mathematical model of this collector is developed. It is shown that the performance depends on three parameters (a) the number of layers (b) the heat transfer coefficient across each layer (c) the absorption properties of the working fluid.Thermal performance predictions are made and compared with a selective flat plate collector operating in a once-through mode. For all practical designs the multiple layer collector is inferior to the selective surface collector.A further design is considered in which two liquid layers are insulated with an air gap. Computer predictions show that this design cannot improve on the flat plate collector. These predictions are confirmed with experimental tests carried out on flat plate and two layer solar collectors. It is concluded that the multiple layer solar collector is not a viable design.     

All-ceramic solar collector and all-ceramic solar roof

A type of all-ceramic solar collector is introduced. These all-ceramic solar collectors are made from ceramics. The material of absorber coating is V–Ti black ceramic. The solar absorptance of absorber coatings with a reticular formation is in the range of 0.93–0.97, without the attenuation of solar absorptance. The fluid passages are integrated with the absorber plate, which naturally formed in the process of shaping. The integration between fluid passage and absorber plate is good to transfer heat from the absorber plate to the fluid. The thermal efficiency of all-ceramic solar system is more than 50%. The all-ceramic solar system can integrate well with building roof. All-ceramic collector and system are characterized by low cost and long lifetime. Such characteristics reduce the cost of solar energy utilization.     

非正南方向太阳集热器面积补偿的理论研究

该文以昆明和北京为例,对我国南北地区分别选用平板型管翼式集热器和圆柱吸热体真空管集热器进行了模拟计算。结果显示,水平面上日均太阳辐射、环境温度、屋顶方位及倾角对集热面积补偿有不同程度的影响;其中,屋顶方位角和倾角是影响集热器处于非正南和正南方向且最佳倾角时采光面积之比A/A0的主要因素。本文的研究成果可为太阳能建筑一体化设计提供部分有价值的参考数据。     

Theoretical and Experimental Studies of the Ultra-Thin-Channel Solar Water Collector

Ultra-thin-channel solar water collector efficiency (UCSWC) was investigated theoretically and experimentally. An ultra-thin-channel solar water collector was constructed using several flat plates with an ultra-thin fluid channel formed using an adjustable flexible silicon frame inserted between the absorber plate and bottom plate. The advantages of the ultra-thin-channel solar water collector are low absorber plate temperature and low total water mass flow rate, resulting in considerable collector efficiency improvement with high outlet fluid temperature and low pump power requirement. A simple and general modeling method was developed to predict the collector efficiencies and mean temperatures of the glass cover, absorber plate and fluid. Good agreement was achieved between the calculated and experimental values. The superior collector efficiencies of the UCSWC are obtained as 82.2% and 75.5% for the inlet temperatures 30°C and 70°C, respectively, operating at a total fluid mass flow 8.3 × 10^?3 kg/s and solar radiation incident of 1100 W/m².     

Effect of Water Flow over the Glass on the Performance of a Solar Still Coupled with a Flat Plate Solar Collector†

In this communication a transient analysis of a solar distillation system with water flow over the glass cover is presented. The system comprises of a single basin solar still coupled with a flat plate solar collector. Due to the increased difference between water and glass temperatures the yield of this system is significantly increased. The performance of this system has been compared with that of a simple single basin solar still (SBSS), SBSS with water flow over it and SBSS coupled with a flat plate collector; and it is concluded that a SBSS with water flow over it shows the best performance.     

Numerical analysis on the thermal performance of a roof-integrated flat-plate solar collector assembly

A numerical experiment has been carried out to study the thermal performance of a large solar collector assembly, which could be integrated as part of the roof structure without undue difficulties. The collector assembly consists of a network of riser tubes and headers as if rows of flat-plate collectors are connected in series to form a large flat-plate collector. Results show that the thermal efficiency of the collector assembly is mainly influenced by the number of riser tubes, collector aspect ratio (H/W), mass flow rate, thermal conductivity and thickness of absorber plate. Differences in the range of 2.5%–8% were detected depending on the specific parameter tested.     

Experience with a large solar DHW system in Denmark—The Nordic solar heating demonstration project

A demonstration project with a large roof integrated solar collector for domestic hot water (DHW) was built in 1984, for the KAB Building Society, in Ballerup near Copenhagen, as part of a Nordic cooperation on solar energy. The project had received funding from the Nordic Building Research Cooperation (NBS), the Building Research Council in Sweden, and from the Energy Agency in Denmark. The 156 m² solar collector used, replacing an ordinary roof, was developed as an improvement of a Swedish solar collector. Projecting the system was performed by Danish and Swedish consultant engineers, and the Thermal Insulation Laboratory at the Technical University of Denmark was responsible for realizing the project and the following monitoring programme. Two different selective absorber types of equal size were used for the solar collector construction. One was a Swedish pipe and fin absorber of aluminium and copper, and the other was a Danish channel plate absorber of stainless steel. For the mentioned solar heating system with approximately 1 m² of solar collector per appartment, a 40% system efficiency of the insolated solar energy has been documented, during a one year monitoring period. Monitored results on a monthly basis, together with a discussion on difference in yield between the two different absorber types used, and operation experience, are presented.     

Heat transfer analysis of low thermal conductivity solar energy absorbers

Polymers have been proven to be high potential low-cost materials for the design and mass production not only for ordinary solar water heaters but also for very simple large size, modular solar collectors, suitable for easy erection of large solar heating plants. Their major drawback for solar–thermal conversion applications is their low thermal conductivity, which prohibits their use unless an appropriate absorber design is employed. The low thermal conductivity of polymers has imposed the need of a particular absorber design, which is basically composed of a pair of dark, closely spaced parallel plates at the top of which solar radiation is absorbed, forming a thin channel for the flow of the heat transfer fluid. The aim of the present work is to investigate the particular limitations of this polymer plate absorber design, for a wide range of collector loss and convective heat transfer coefficients between heat transfer fluid and absorber plate. The aim is also to calculate the particular collector efficiency factors and conditions under which the associated collector performance parameters should be modified to account for the finite absorber plate conductance. This conductance was proven to be another decisive absorber design parameter, improper selection of which may probably lead to strong deterioration of the collector efficiency.