基于TRNSYS的太阳能耦合燃料电池热电联产系统的模拟研究

文章建立了太阳能耦合燃料电池热电联产系统的TRNSYS模型。采用镇江地区的天气数据(太阳直射辐射强度和环境温度),模拟了该系统在各典型日的火用效率。得出热电联产系统的集热量、发电量及火用效率均随着太阳辐射强度的增强而提高的结论。基于此,将热电联产系统的生命周期成本设为优化目标,采用Hooke-Jeeves算法对关键运行参数进行优化。结果表明:当集热器面积为15 m^(2),单电池片数为60个,蓄热水箱容积为5 m^(2),太阳能电池板面积为5 m^(2)时,可以获得最小的生命周期成本49.1万元,比常规模型降低11.7%;优化后的热电联产系统在典型日的火用效率为50%~57%,较常规热电联产系统提升50.0%~85.7%。

全玻璃真空管太阳能集热器对流换热试验与模拟

以可再生能源总能系统为研究背景,通过搭建太阳能辅助燃料电池试验平台,逐步完成不同涂层材料、内置导流板太阳能集热器自然对流试验研究;在试验验证基础上,分别建立太阳能集热器自然对流和强迫对流三维数学模型,应用场协同和火积理论分析流动和传热数据。自然对流研究表明,吸收率在0.95～1.0、发射率在0.06～0.16时,随吸收率升高,发射率降低,热效率升高1.71%,火积增量逐渐增大;加装导流板后,真空管内部混流消失,底部流动得到强化,实验热效率提高2.17%;确定全玻璃真空管热水器导流板合理板厚为2 mm,合理板长为距离真空管底部60～100 mm,合理位置为中心线以上16～20 mm;强迫对流研究表明,横双排集热器雷诺和努赛尔数、火积增量均高于竖单排集热器,火积耗散低于竖单排集热器。确定太阳能辅助燃料电池集热场在中低温条件下,自然对流采用内置导流板集热器,强迫对流采用横双排集热器。

全玻璃真空管太阳能热水器实验和模拟研究

以太阳能辅助燃料电池为研究背景,搭建不同管长和管径、不同涂层材料的内置导流板热水器,逐步完成全玻璃真空管太阳能热水器实验和模拟研究.建立太阳能热水器三维数学模型,以场协同和理论为指导,分析热水器强化传热数据.研究结果表明,真空管出口射流区域的场协同性最高,水箱内部存在横向的扰流;真空管内加装导流板后,管内冷热流体混流减弱,强化了真空管底部流动,真空管内耗散最小,水箱内温度梯度减小,场协同度最高.太阳能辅助燃料电池集热场在自然对流条件下,宜采用内置导流板热水器.

Experiment and numerical simulation on flow and heat transfer in all-glass evacuated tube solar collectors

The experimental study of natural convection in allglass evacuated tube solar collectors is performed through the experimental platform of the solar-assisted fuel cell system.The experimental facility includes solar collectors with different length and diameter tubes, different coating materials, and with / without guide plates, respectively. Threedimensional mathematical models on natural and forced convections in the solar collectors are established and the experimental data is validated by field synergy and entransy principles. The results of natural convection show that the water temperature increases and thermal efficiency decreases gradually with the evacuated tube length. The thermal efficiency increases when absorption rates increase from 0. 95 to 1. 0 and emission rates decrease from 0. 16 to 0. 06. The thermal efficiency of solar collectors is increased after being equipped with the guide plate, which is attributed to the disappearance of the mixed flowand the enhancement of the heat transfer at the bottom of the evacuated tube. The results of forced convertion indicate that the Reynolds, Nusselt and entransy increments of the horizontal double collectors are higher than those of the vertical single collector while the entransy dissipation is lower than that of the vertical single collector. It is concluded that the solar collectors with guide plates are suitable for natural convection while the double horizontal collectors are suitable for forced convection in the thermal field of solar-assisted fuel cell systems with lowand medium temperatures.

未来的高新技术住宅

未来的家庭住宅,外观让你爷爷奶奶看了感受到舒心,而结构则是高技术的产物.一些技术,象虚拟建筑师.会使你史无前例地操纵住宅的设计与建造.另一些技术,象自动净化表面,则对你的生活赋予充分的自由.还有一些,比如环保燃料电池,在地下室供电,把住宅对环境的不良影响降到最低.这些技术最终会使现在的住宅面貌大改.

纳米T_iO_2初探

通过对纳米TiO2 的特性了解 ,指出了纳米TiO2 的广泛应用及其良好的发展前景。

The Use of Hydrogen as a Fuel for Inland Waterway Units

Escalating apprehension about the harmful effects of widespread use of conventional fossil fuels in the marine field and in internal combustion engines in general, has led to a vast amount of efforts and the directing of large capital investment towards research and development of sustainable alternative energy sources. One of the most promising and abundant of these sources is hydrogen. Firstly, the use of current fossil fuels is. discussed focusing on the emissions and economic sides to emphasize the need for a new, cleaner and renewable fuel with particular reference to hydrogen as a suitable possible alternative. Hydrogen properties, production and storage methods are then reviewed along with its suitability from the economical point of view. Finally, a cost analysis for the use of hydrogen in internal combustion engines is carried out to illustrate the benefits of its use as a replacement for diesel. The outcome of this cost analysis shows that 98% of the capital expenditure is consumed by the equipment, and 68.3% of the total cost of the equipment is spent on the solar photovoltaic cells. The hydrogen plant is classified as a large investment project because of its high initial cost which is about 1 billion US$; but this is justified because hydrogen is produced in a totally green way. When hydrogen is used as a fuel, no harmful emissions are obtained.

Analysis of an SME using Silicon and Flexible Organic Solar Cells as Replacements for Fossil Fuel Sources of Electricity in UK and Iraq

Currently, 86% of the energy originates from fossil fuelsforelectricity. These are expected to run out, causing severe environmental damage threatening future generations. The total impact of Small and Medium Enterprises （SMEs） on the economy is significant. Solar cells harness the sun＇s energy to generate electricity in an environmentally friendly manner. This study compares silicon solar cells to flexible Organic Photovoltaic solar cells （OPV） for electricity energy for a micro-business in the UK and Iraq. It shows that it is feasible to replace existing fossil fuel sources with solar cells in Iraq due to a greater amount of solar radiation striking the earth＇s surface. Flexible solar cells can replace a proportion of the energy requirements in the UK and a larger proportion in Iraq. Using existing 20% efficient solar cells, 28% and 83% of the energy requirements of the microbusiness can be replaced in UK and Iraq respectively. Assuming 20% efficiency for solar cells placed on windows, 74% and 220% of the energy requirements of UK and Kurdistan can be replaced respectively and the surplus stored.

Energy Technologies as Power Storage and Generation towards the Business Model in Sustainable Society

Energy security and CO2 reduction are one of the most important issues as well as food matter in the 21st century. Power storage and power generation will contribute to solution of these issues. Electrochemical storage of Li-ion batteries is widely applied in mobile applications, and the new application for automobile using has been actively developed and partially realized. And the Li-ion battery storage in smart grid systems is also expected. Automobile use and storage use have large market size same as the size of memory semiconductor. For these diverse applications, material research and development are key technologies. From power generation, Solid Oxide Fuel Cell and Dye Sensitized Solar Cell are much expected as new technology devices. The business model is important to realize these new devices considering the value compared with the existing methods.

Climate technology promotion in the Republic of Korea

The implementation of climate technologies and their commercialization ultimately depends on the success of their research and development(R&D) projects. In the Republic of Korea(ROK), twenty-seven climate technologies were selected to boost the greening of existing industries and to develop new green industries to promote a sustainable climate technology development strategy. Rechargeable battery technology, carbon capture and storage(CCS) technology, smart grids, and sewage treatment are all research areas expected to have tangible outcomes in the forthcoming years. As such, they were included in a comprehensive R&D plan for climate technology advancement, which places an emphasis on climate technology development and commercialization strategy. In this study, the R&D plan of the ROK is reviewed by examining its six core climate technology programs: solar cells, fuel cells, bioenergy, rechargeable battery technology, information technology(IT) applications for the power sector, and CCS technology in detail. The climate policy in the ROK aims to find new economic growth engines and to develop new business opportunities while actively participating in international efforts to combat climate change.

Detailed Study on Establishing a PV Power Plant to Generate Electricity in Saudi Arabia

Photvoltiacs （PV） power plants have beell built all over the world, and are successfully proven as one of the important substitutes of alternative energy sources. In the Kingdom of Saudi Arabia, the electricity demand will double in the next 15 years, dramatically increasing fuel consumption. To meet this huge load growth, there has been some series of movements to find out solutions. This research aims at studying the feasibility of design and construction of a solar power plant using photovoltaic cells in Saudi Arabia from the geographic, economic and technical perspectives. It＇s concluded that PV power is competitive with the conventional capacity required to meet ＂peak＂ power demand and represents an opportunity for reducing fuel consumption in Saudi Arabia.

Highlights on inorganic solid state chemistry and energy materials

This review highlights the recent research progress on inorganic solid state energy materials in China,from synthesis and fundamental properties to their applications.It describes the significant contributions of Chinese scholars in the field of inorganic solid state chemistry and energy materials including green catalysts,fuel cells,lithium batteries,solar cells,hydrogen storage materials,thermoelectric materials,luminescent materials and superconductors,and then outlines the ongoing rapid progress of novel inorganic solid state materials and the development of reliable and reproducible preparation methods for inorganic solid state materials in China.Finally,we conclude the paper by considering future developments of inorganic solid state chemistry and energy materials in China.

Fuel-optimal trajectory design using solar electric propulsion under power constraints and performance degradation

The fuel-optimal transfer trajectories using solar electric propulsion are designed considering the power constraints and solar array performance degradation.Three different performance degradation models including linear,positive and negative exponential degradations are used in the analysis of three typical rendezvous missions including Apophis,Venus and Ceres,respectively.The optimal control problem is formulated using the calculus of variations and Pontryagin’s maximum principle,which leads to a bang-bang control that is solved by indirect method combined with a homotopic technique.In demonstrating the effects of the power constraints and solar array performance degradation on the power budget and fuel consumption,the time histories of the power profile and the fuel consumptions are compared for the three missions.This study indicates that it is necessary to consider the power constraints and solar array performance degradation for the SEP-based low-thrust trajectory design,espacially for long-duration outbound flights.