一种新型两用太阳能集热器

报导了一种新型两用太阳能集热器,它的换热效率高,既可用于加热空气,也可用于加热水,达到一套装置实现两种功能。     

太阳能热水器集热器安装位置,方向和倾角的确定

描述了太阳能热水器集热器安装位置,方向和倾角的确定方法。     

一种新型的太阳能集热器

<正> 美国芝家哥大学的物理学家们设计并试验成功了一种新型的高效太阳能集热器。这种装置是根据非反射光学原理制成的,准备做为宽频带阳光辐射能源。集热器将提供足够的动力来发射某些类型的激光。这类激光在科学技术     

新型热管式真空管太阳能集热器

分析了新型热管式真空管太阳能集热器的开发背景，介绍了其工作原理，对集热元件、集热盒内关键零件的结构和特点以及产品的固定安装、连接方式进行了详细说明，同时提供了产品热性能测试报告和工程应用实例。     

新型热管式真空管太阳能集热器

分析了新型热管式真空管太阳能集热器的开发背景,介绍了其工作原理,对集热元件、集热盒内关键零件的结构和特点以及产品的固定安装、连接方式进行了详细说明,同时提供了产品热性能测试报告和工程应用实例.     

平板太阳能集热器如何从受冷遇迈向发展

20世纪80年代曾占我国太阳能热水器统治地位的平板太阳能集热器、热水器在近十多年内,已逐渐被全玻璃真空管太阳能热水器替代。市场份额逐年下降,现已降至15%左右。然而同期国外太阳能集热器市场     

蜂窝热管平板式太阳能热水器的实验研究

把蜂窝技术和热管技术结合起来应用于平板式太阳能热水器，可以大大减少热损失，提高日平均效率。经多次实验证明，蜂窝热管平板式太阳能热水器的日平均效率可以比真空管式热水器的高，热损系数则要小很多，具有推广应用价值。     

多孔介质辅助平板式太阳能集热器热性能强化的数值仿真研究

多孔介质材料具有良好的传热和蓄热性能。设计了新型多孔介质辅助平板式太阳能集热器的二维数值仿真模型,对其内部热性能进行了数值模拟,研究多孔介质块的形状(矩形、梯形、三角形结构)、布置数量和渗透率(达西数Da=10^-5～10^-2)等因素对平板式太阳能集热器热性能强化的影响;然后考虑到插入多孔介质伴随的压降和摩擦阻力损失,提出了评价集热器传热性能与阻力损失的性能评估标准。研究结果表明：在平板式太阳能集热器换热通道插入4种不同形状的多孔介质块,矩形多孔介质块背部附近区域更易产生涡区,集热器内传热性能最强,但通道内流动阻力系数大,从而导致阻力损失大。当多孔介质区域总长度一定时,随着多孔介质块布置数量的增加,涡区数量相应增加,集热器内传热性能加强,且通道内流动阻力损失呈现先增加后降低的规律。多孔介质块渗透率对集热器传热性能的影响显著,当Da=10^-2时,集热器传热性能最强。集热器内多孔介质块布置任意数量、高渗透率(Da=10^-2)条件下,矩形多孔介质块的性能评估标准最佳;在多孔介质块布置数量(N=6)较多、低渗...     

一种新型的平板太阳能集热器

平板太阳能集热器就是让太阳光通过透明盖板,照在吸热板上,使光能变为热能,通过与吸热板紧密接触的管道,把热量传给水. 平板太阳能集热器的主要缺点是自然对流热损和辐射热损失大,理想的平板太阳能集热器就是要抵制自然对流热损失,同时降低辐射热损失.     

A new transparently insulated, bifacially irradiated solar flat-plate collector

A new type of transparently insulated flat-plate collector was developed. It reaches higher efficiencies at low irradiation values or high operating temperatures than any other collector type known. Both sides of its absorber are covered with transparent insulation material and both sides are irradiated. Thus, the heat losses of the collector related to the total absorber area are distinctly reduced. An optical efficiency of η₀ = 0.72 and a temperature dependent U-value of U(ΔT) = (0.95 + 0.0076 ΔTK⁻¹) W m⁻² K⁻¹ were measured with an outdoor test facility. The bifacial-absorber collector is considered to be the best option for the DHW system of the energetically self-sufficient solar house in Freiburg because of its outstanding winter performance.     

Performance of a flat-plate solar collector

The design of a simple solar collector made from corrugated, galvanized-iron sheet is given. Its performance during summer at Allahabad, India, at various flows is presented. To obtain hot water at temperatures higher than 170 deg F, temperature being averaged over an eight-hour period, a flow of only about 1 lb/hr-ft² should be allowed. The supply of hot water from the collector will be used in an absorption-type solar cooler.     

Thermodynamic optimization of solar flat-plate collector

Second-law modeling of flat-plate collectors is performed with the objective of describing collector performance when entropy generation is minimum. Effects of irreversibility are demonstrated. Factors mostly effecting the generation of entropy are discussed.     

Analysis and performance of flat-plate solar collector arrays

A new discrete numerical model is proposed to calculate the flow and temperature distribution in solar collector arrays. The flow nonuniformity, the longitudinal heat conduction, and the buoyancy effect are all taken into account in the analysis. The numerical results of pressure and temperature distribution are found in agreement with the experimental results. It is found that the flow nonuniformity has detrimental effect on the thermal performance of collector array.     

General thermal analysis of parallel-flow flat-plate solar collector absorbers

Improved equations are formulated for the transfer of heat in flat-plate solar collector absorbers, including a shape factor accounting for details of flow duct designs, and developing heat transport in the ducts. Approximate, analytical solutions are obtained in terms of perturbation series, which are applicable to practical collectors with lengths much greater than the distance between flow ducts.The primary result of the analysis is a universal-type design equation, or chart, which determines the collector efficiency factor for any duct design, heat transfer development, or other absorber-plate parameter. Collector performance is stated in terms of an effectiveness/number-of-transfer-unit relationship. Ease of use and utility of the design chart is illustrated by examples.     

Performance of a thermal trap flat-plate solar energy collector

The performance of a thermal trap flat-plate solar energy collector has been investigated theoretically and validated experimentally, from the point of view of stagnation temperature. The theoretical model is based on the periodic solution of the heat conduction equation and takes into account the internal emission of the thermal trap material. The model explains the experimental measurements fairly well. It is found that the trap material should have an optimal thickness in order to obtain the maximum plate temperature.The thickness of the air gap between the trap material and the cover has only a very marginal effect on the stagnation temperature.