中温太阳能热管接收器的开发与传热分析

介绍了一种新型的用于槽式太阳能热发电的中温(250～400℃)热管接收器,其结构为热管蒸发段外套单层玻璃套管,玻璃套管与热管之间抽真空,热管蒸发段外壁上涂有选择性吸收涂层,作为吸收层.该新型热管接收器主要用于直接产蒸汽系统.文中分析了该新型热管接收器的特点,并分3段模拟计算了采用该接收器的抛物面槽式太阳能集热器的集热效率和接收器的散热损失.结果表明,新开发的热管接收器结构简单、维护方便、热效率较高,适用于槽式太阳能集热器.     

太阳能重力热管相变传热过程的数值模拟研究

为了提高高寒地区住房的太阳能利用率,降低建筑能耗,增加住房的蓄热能力,提升住房的热舒适性,提出将太阳能平板集热器与重力热管集成于外墙的方法;通过分析太阳能重力热管相变传热过程,建立了重力热管相变传热的数学模型,并通过试验对模型进行了验证。结果显示：利用验证的模型对太阳能重力热管的结构进行优化设计,提高了太阳能的利用效率。     

热管真空管集热器及太阳能热水系统

热管真空管集热器是继闷晒式、平板式、全玻璃真空管集热器后的第四代太阳能集热产品．在太阳能领域得到了广泛的应用。分析了热管真空管的原理、结构及传热特性;以国外产品为例,论述了热管真空管集热器的特点及工作性能;对直流式热管真空管热水系统和典型的间接式供热供暖及泳池热水系统进行了分析。     

专利信息

太阳能热管换热器本实用新型是利用热管技术制成的高效太阳能加热器。它包括一个太阳能热管吸热片和一个热管散热片,热管吸热片与热管散热片之间通过固定连接的导通管连为一体,热管散热片固定安装在一个容器内,构成太阳能热管换热器。它的工作原理是,热管吸热片经阳光的照射,将光能转换为热能,热管吸热片内     

CPC热管式真空管集热器的集热效率研究

介绍了CPC(compound parabolic concentrator)热管式真空管集热器的结构,对CPC热管式真空管太阳能集热器进行了传热分析,并对CPC热管式真空管集热器、热管式真空管集热器和CPC热管式集热器的集热效率进行了对比计算。CPC热管式真空管集热器的集热效率的理论计算和试验结果表明:CPC热管式真空管集热器的集热效率最佳。     

热管式真空集热管的研制与应用

阐述了热管式真空集热管的基本构成及其特性,分析了热管式真空集热管研制的几个主要方面:热管和吸热板、玻璃管、选择性吸收涂层,玻璃一金属封接,真空度、聚光板.介绍了热管式真空集热管在太阳能热水系统、太阳热发电、太阳能制冷与空调、太阳能海水淡化等方面的应用,表明热管式真空集热管在太阳能中高温领域中具有广泛应用前景.     

热管式真空太阳能集热管及其应用

热管式真空太阳能集热管(简称热管式真空管或热管真空管),是金属吸热体太阳能真空集热管的一种,具备了全玻璃真空管良好的集热和保温性能,以及平板式集热器金属的良好导热性和机械强度。它以热管作为核心传热原件,具有其他类型的太阳能集热产品不可替代的优势。热管真空     

集中供热热管太阳能集热系统

在原有平板集热器的基础上研制了一种与建筑结合的太阳能集中供热热管系统，并对策略热管的传热机理进行了分析，提出正常工况下该热管的集总参数模型，给出了热管的倾角范围。文中给出了该集热系统的理论预测和实验结果对比。热管太阳能集热器的理论模型以Duffie 和Beckman理论（1980）为基础，修改后用于能量传输。该文还给出了该集热器和传统的太阳能集热器的对比试验结果。热管太阳能集热器的瞬时效率在早上低于传统的太阳能集热器的，而当热管达到工作温度时，前者高于后者。     

高温热管太阳能接收器的开发及传热特性分析

分析了碟式太阳能热发电系统接收器的工作特点及所应满足的条件,针对目前高温热管接收器的现状,提出了组合式热管接收器的开发理念,并从接收器总体结构、热管单元结构以及接收器工作原理等方面做了详细阐述。为探讨所开发接收器的传热特性,对热管接收器的传热过程进行了分析计算,结果表明组合式高温热管接收器具有优良的热传递性能,可以适应碟式太阳能热发电系统的运行需求。     

新型分离热管式太阳能热水器

一前言本文介绍的新型分离热管,原理明了、结构简单、加工容易,生产设备及工艺均与现有热管一样;本文所述的分离热管太阳能热水器,自动运行,无需消耗额外能源,适合在寒冷地区分体安装。     

Theoretical investigation of the performance of a novel loop heat pipe solar water heating system for use in Beijing,China

A novel loop heat pipe (LHP) solar water heating system for typical apartment buildings in Beijing was designed to enable effective collection of solar heat, distance transport, and efficient conversion of solar heat into hot water. Taking consideration of the heat balances occurring in various parts of the loop, such as the solar absorber, heat pipe loop, heat exchanger and storage tank, a computer model was developed to investigate the thermal performance of the system. With the specified system structure, the efficiency of the solar system was found to be a function of its operational characteristics - working temperature of the loop heat pipe, water flow rate across the heat exchanger, and external parameters, including ambient temperature, temperature of water across the exchanger and solar radiation. The relationship between the efficiency of the system and these parameters was established, analysed and discussed in detail. The study suggested that the loop heat pipe should be operated at around 72 °C and the water across the heat exchanger should be maintained at 5.1 l/min. Any variation in system structure, i.e., glazing cover and height difference between the absorber and heat exchanger, would lead to different system performance. The glazing covers could be made using either borosilicate or polycarbonate, but borosilicate is to be preferred as it performs better and achieves higher efficiency at higher temperature operation. The height difference between the absorber and heat exchanger in the design was 1.9 m which is an adequate distance causing no constraint to heat pipe heat transfer. These simulation results were validated with the primary testing results.     

真空玻璃盖板热管平板式太阳能热水器的研制

介绍了研究成功的采用真空玻璃盖板的热管平板式太阳能热水器,测试了其性能,并与全玻璃真空管太阳能热水器和蜂窝热管太阳能热水器进行了比较。实测得到,真空玻璃盖板热管平板式热水器的日平均效率比后两分别大13．3％和6．5％,平均热损系数比后两分别小52．5％和21．5％。真空玻璃盖板平板式太阳能热水器性能优越,有很好的应用前景。     

CPC内聚光式热管集热管温度特性研究

为提高太阳能热水系统的输出温度,将CPC聚光技术应用于热管式真空集热管中,开发了一种新型的CPC内聚光式热管集热管。对该集热管建立数学模型,模拟计算其传热过程,获得了导热肋片温度、热管冷凝段温度等参数随太阳辐射强度的变化规律,并通过试验验证了数学模型的可靠性;与常规热管式真空管集热管传热特性相对比,证实了该集热管可大幅提高太阳能热水器输出温度。     

The potential applications and advantages of powering solar air-conditioning systems using concentrator augmented solar collectors

Non-concentrated evacuated tube heat pipe solar collectors have been reported to show higher fluid temperatures with improved thermal performance in the low to medium temperature range (?60 °C) due to low heat losses but suffer higher heat losses at the medium to higher temperature range (?80 °C) which reduces their efficiency compared to concentrated evacuated tube heat pipe solar collectors. To operate as stand-alone systems capable of attaining temperatures in the range of 70-120 °C, an innovative concentrator augmented solar collector can be an attractive option. The performance of a combined low-concentrator augmented solar collector in an array of evacuated tube heat pipe solar collectors defined as concentrator augmented evacuated tube heat pipe array (CAETHPA) and an array of evacuated tube heat pipe collectors (ETHPC) were tested and compared and results presented in this paper. The analysis of the experimental data allows concluding that the use of a CAETHPA is a more efficient alternative for integrating renewable energy into buildings with higher fluid temperature response, energy collection and lower heat loss coefficient compared to the use of evacuated tube heat pipe collector array (ETHPA).     

Session D: Co-products/Animal Feed 2. Energy Related Aspects for Fuel Ethanol Production

In this paper, various ways for improving the thermal performance of heat pipe solar water heaters were provided based on the heat transfer analysis and have been improved by experiments and practical use. It is shown that the increase of the heat transfer space of heat pipe condensation section is the effective way to improve the instantaneous efficiency of heat pipe solar water heater, and the increase of L/D ratio of heat pipe is also important for improving its whole day performance.     

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。     

A Review on the Heat Pipe Photovoltaic/Thermal(PV/T) System

The Photovoltaic/thermal(PV/T) system combines the conventional PV panel with solar collector into one integrated system, which could achieve the function of generating power and providing thermal energy at the same time. Recently, it has become the most promising solar system for building applications. Most of the PV/T systems use water as the coolant, which could cause freezing problem in winter. To overcome this problem, the heat pipe PV/T system is developed to provide electrical and thermal energy stably without the seasonal barrier. Although some published review works have involved this type of PV/T system, they just stated a simple introduction on it, acting as a small part of their works. This paper focuses on the heat pipe PV/T system independently and provides a comprehensive and in-depth analysis of its performance. Firstly, the structure and operational principles of the heat pipe PV/T module and system are introduced concisely. Then the features and performance of different types of heat pipe PV/T systems, i.e., integral heat pipe, loop heat pipe, and pulsating heat pipe PV/T system, are presented and analyzed. This is followed by the review on the performance of the systems which combine heat pipe PV/T module and other devices. Finally, the research gaps in this field are identified, and some future research trends and directions are recommended.     

Thermal management of solar cells using a nano‐coated heat pipe plate: an indoor experimental study

With temperature increasing, the photovoltaic efficiency of solar cells is reduced significantly. Such an efficiency loss may offset the efficiency improvement because of the development of the photovoltaic technology. This paper provides a novel approach for efficiency loss recovery of solar cells. Specifically, a nano‐coated heat pipe plate was integrated with the solar panel to remove heat from the hotspots on solar cells. This study concerns the indoor experiments of a commercial solar cell thermally managed with a heat pipe plate. The temperature rise and non‐uniformity on the solar panel were quantified in different light irradiances. With thermal management by the heat pipe plate, the solar panel shows a temperature‐rise reduction of 47–50%. This implies that half of the efficiency loss of the solar cell can be recovered. In addition, the temperature variation within the solar panel is reduced to 1.0–2.5 °C, which is beneficial in prolonging the longevity of the solar cell. In the experiments, the heat pipe plate can provide a cooling flux of 380 W/m² with light irradiance below 1000 W/m². By incorporating the heat pipe plate with a water jacket, the heat removal flux could be improved to 600 W/m², leading to a solar cell temperature of a few degrees higher than the ambient. Copyright © 2016 John Wiley & Sons, Ltd.