甘肃省小水电冬季运行的冰害

一、基本概况甘肃的地理位置,深居大陆内部,纬度32°13′～42°57′,南北相距约10个纬度,经度92°13′～108°46′,东西跨越16个经度.又处于青藏、黄土、蒙古三大高原的交汇地带,境内地势高亢,地形复杂.大部分地区海拔都在1000米以上.全省年平均气温从祁连山地和甘南高原的4℃以下,递增到陇南南14℃,最冷月(一月)平均气温从陇南山地0℃,陇中的黄土高原的-6℃,河西、甘南高原-10℃向祁连山、北山山地逐减到-12℃.全年无霜冻期(日最低气温在0℃以上)陇南220天,陇中180天、河西160天.除陇南部分海拔在1000米以下地区外,全省大部分地区无霜冻期短、冰冻期长、冰害严重.对小水电站的正常运行影响很大,严重的地区逼迫电站停运.     

老边区“四结合”、“五配套”生态模式技术经济分析

1立项依据 　　老边区是辽宁省营口市近郊区,东、南、北三面环抱营口市区,处于辽东湾东北部,辽河三角洲下游地带,东经 122° 07′～ 122° 27′,北纬 40° 27′～ 40° 45′。区内地势较平坦,自东向西倾斜,土地面积 305 km2,耕地面积 9 870 hm2。全区太阳能资源丰富,年日照时数为 2 917 h左右,东部略少,年太阳总辐射量为 (586.2～ 598.7)× 104 kJ/m2,生理辐射量为 330.7× 104 kJ/m2,年平均日照率为 67％,冬季多晴天,且空气污染较轻,大气透明度较高,为太阳房的使用和冬季温室生产提供了优越的资源条件。随着市场经济的发…     

山东省太阳能集热器最佳倾角的研究

本文基于３０年的气象观测资料，从理论上导出了山东省各地月，季，年及典型时段太阳总辐射的最佳倾角。一般年最佳倾角与所处纬度差别不大，对于全年使用的太阳能集热器，为保证冬季更好地使用，将倾角加大２０°左右，在冬季可多接收总辐射量６％－１０％，而４－１０月间使用的集热器将倾角减少２０°左右，样增加辐射疸２％－６％。     

搞好建筑节能大力发展被动式太阳能采暖房(续)

三、发展太阳房的可行性和对策被动式太阳能建筑在我国从无到有,从点到面,总趋势是好的。我国不仅有优越的自然条件,而且在技术、经济上也具备发展太阳房的可行条件。我国太阳能资源十分丰富,全国太阳能资源丰富带(Ⅰ区,年辐射量大于628KJ/cm~2、年)和较丰富带(Ⅱ区,年辐射量为502—628KJ/cm~2、年)大都在北纬35°以北地区,其日照时数≥6小时的年总天数均大于250天。其中又以西藏、青海、甘肃西部、新疆南部的资源条件最好。处于北方采暖边缘地带的山东、     

北京地区的太阳辐射分析

根据北京市1958年-2000年的太阳辐射和日照时间的日值数据资料,对北京市的年太阳辐射历年平均 值进行了计算,分析了北京市太阳辐射量的长期变化;研究了太阳总辐射和日照时间之间的关系以及散射辐射 与总辐射之间的关系,分别得到了估算太阳总辐射和散射辐射的经验公式,研究中对所得到的经验公式进行了 误差统计,结果表明能满足工程应用的要求。     

太阳能采暖猪舍

保定位于河北省中部,太行山东麓。地理位置在北纬38°15′～39°57′,东经113°45′～116°21′之间。辖区内平均日照时数为2880.2h/a,日照率为0.66;平均太阳辐射总量为5.9×10~6kJ/(m~2·a),是我国北方太阳能资源较丰富地区之一。     

扩压叶栅中端壁附面层抽吸对流场品质调控的研究

为调控平面扩压叶栅流场品质、使测量结果满足二维性,在叶栅端壁增加附面层抽吸装置。采用试验校核的数值方法,分析了不同抽吸位置、不同抽吸流量、不同冲角时端壁附面层抽吸对平面扩压叶栅出口气流角、轴向密流比和总压损失系数等参数的影响。结果表明：在抽吸位置上,位于叶片中前部的抽吸方案对扩压叶栅流场品质的改善效果相对最好。随抽吸流量增加,流场品质进一步改善,抽吸流量为原型进口流量的3%可使冲角为0°时的轴向密流比降低至0.995,主流区出口气流角偏差小于0.1°;抽吸流量为原型进口流量的2.25%可使计算冲角范围内轴向密流比均降低至1.05以下,主流区出口气流角偏差小于0.2°。冲角在-5°,-3°和0°时端壁抽吸使50%相对叶高位置处平均总压损失降低,冲角在2°,4°时使50%相对叶高位置处平均总压损失增加,损失冲角特性更接近理想二维叶栅。     

2004年《节能技术》全年索引

研究与探讨在线确定凝汽式汽轮机相对内效率的新方法 (1 - 3)……………………低温热水地板辐射供暖间歇运行研究 (1 - 5)……………………………网络热力学的建模方法 (1 - 7)……………………………………………管沟敷设供热管道热损失计算 (1 - 1 0 )……………………………………汽车尾气余热沥青加热装置的研究 (2 - 3)………………………………低温地板辐射采暖系统中辐射板布置方式的优化 (2 - 6)………………估算不同地区月平均太阳散射辐射量数据的研究 (3- 3)………………深圳市能源利用状况的分析 (3- 6)………………………………     

集成探针号动部分的风洞标定

为了验证测量汽轮机内湿蒸汽的探针的性能以及分析流场实验数据,对探针在开式空气风洞和湿蒸汽风洞中作了标定,标定马赫数范围0.1～1.1,气流攻角从-10°～40°,气流偏转角从-10°～10°,这一范围测量得到的标定曲线完全覆盖了汽轮机末级前后可能出现的情况.通过比较在空气、过热蒸汽和湿蒸汽3种介质中的标定数据,提出了可以用空气风洞标定取代复杂的过热蒸汽或湿蒸汽风洞标定的结论.     

带透明蜂窝的太阳空气加热器的实验研究(Ⅰ)--不同结构空气加热器的性能比较

该文报导了对多种带透明蜂窝的太阳空气加热器的实验研究工作.这些空气加热器的结构特点分别为:I型--透明蜂窝作为空气流道的一部分;Ⅱ型--透明蜂窝作为普通盏板使用;Ⅲ型--两级结构,前级为I型,后级为Ⅱ型.作为比照,也做了普通平板型空气加热器的实验.结果表明,I型太阳能空气加热器具有良好的热性能:空气质量流率为55kg/h,进出口平均温差为31℃时,其日平均热效率达64%.这种结构简单的新型太阳空气加热器在太阳能干燥及采暖等领域有很大的潜在应用价值.     

Solar thermal applications in the West Indies

Solar thermal devices have been used in the West Indian islands for over a century. Traditionally, crops such as rice or cocoa have been dried in the sun on drying floors. In the last twenty five years solar water heaters have become commercially available and over 30,000 are now in use in Barbados and about 2000 in Jamaica. Solar stills and solar crop dryers have also been deployed and solar collectors have been used to power solar cookers and adsorption chillers. Compound parabolic concentrating solar collectors have been used for experimental purposes but the high level of diffuse radiation obtained during most months of the year makes concentrating collectors unsuitable.     

Performance analysis of a solar cooker in Turkey

A box‐type solar cooker is designed and its thermal performance is analysed experimentally. The cooker tracks the sun in two axes, altitude and sun azimuth, by hand control for hourly periods. The experimental results show that the tested cooker may be assumed suitable in some cooking processes for specific country conditions. Copyright © 2002 John Wiley & Sons, Ltd.     

上海太阳能技术发展现状及其应用前景

简要介绍了上海的太阳能资源条件,分析了太阳能转换利用的主要技术途径,对上海太阳能技术发展现状和应用前景做了总结。     

Solar dryers in the Asia-Pacific region

The traditional method of solar drying in the Asia-Pacific region is by open-air drying where the product to be dried is exposed directly to the sun. The disadvantages of this traditional form of drying are many. Dirt, dust, and wind-blown debris, insect infestation, human and animal interference, will result in contamination of the product. Speed of drying and quality of dried product will be reduced due to over/under drying, intermittent sunshine, interruption and wetting by rain. Mechanical solar drying using natural convection or forced circulation would minimise these disadvantages. The author of this paper visited a number of countries and studied the numerous designs available for solar drying in the region. Three types of solar dryers considered by the author as having the best potential for development in the Asia-Pacific Region are discussed. These are the natural convection cabinet-type solar dryer, the forced convection indirect solar dryer, and the greenhouse-type solar dryer.     

Investigating different diffuse solar radiation models to analyse solar radiation on inclined surfaces in Oman

In this paper, a detailed analysis of the solar radiation on horizontal and tilted surfaces for six locations in Oman is presented. The locations are (from North to South): Majis/Sohar, Sur, Fahud, Masira, Marmul, and Salalah. These locations spread over Oman and cover different types of landscape. The method is validated through the use of measured data. The effect of tilt angle and orientation on the incident solar radiation is presented along with optimum surface tilt angles and directions for maximum solar radiation collection in these six locations. The solar radiation models used in this paper show good agreement with measured data. The results presented in this paper are extremely useful for quick estimation of solar radiation for calculations of buildings’ cooling load and solar collector system performance. This can be easily extended for other locations with similar landscapes and geographical conditions.     

Technological aspects of advancement in low-capacity solar thermal desalination units

Drinking water of acceptable quality has become a scarce commodity. The standard high-capacity desalination methods such as multi-stage flash evaporation and multi-effect evaporation, vapour compression and reverse osmosis are reliable in the range of about 100–500,000 m³/day fresh-water productions. However, the wide-scale implementations of these methods face numerous technological, economic and political barriers and these methods are not used in decentralised regions with a poor infrastructure due to their permanent need of qualified maintenance and electricity supply. In this paper, various low-capacity solar thermal desalination systems, with fresh-water output production in the range of 10–150 l/day for the use in rural areas, are reviewed and classified based on five technological aspects such as the development of the technology of the systems, the applicability of high-capacity thermal desalination technologies, the enhancement of solar heat collectors, the hybridisation of thermal desalination technologies and heat recovery processes. Most of the reviewed systems are in the research stage and have not cleared economic feasibility such as the price per cubic metre of water that may stimulate the decision-maker to direct these studies into the actual commercial applications to find a solution to the water scarcity problem in isolated and remote areas. Although many of the developed systems have several novel and valuable features, more efforts are required for further investigating more efficient, economic and applicable solar energy-driven low-capacity desalination systems.     

非晶硅太阳能路灯系统的设计

介绍太阳能路灯系统的组成,各部分的工作原理、工作特点,并以沈阳汉锋工厂内安装的太阳能路灯为例,来说明非晶硅太阳能路灯系统的设计方法。具有弱光性、低成本的非晶硅太阳能电池与高亮度、长寿命的LED光源相结合将是未来照明工程的发展趋势。     

太阳时角对槽式聚光器焦线位置的影响

在讨论太阳时角对槽式聚光器焦线位置影响的基础上,建立了因焦线运动导致太阳辐射损失的理论模型.通过对昆明晴天不同节气下的焦线运动和太阳辐射损失的分析和计算,得到了焦线随时角变化的一般规律以及瞬时太阳辐射强度损失和不同时段的太阳辐射相对损失率,并与实验进行了对比.针对焦线运动的特点,提出了对槽式集热系统接收器的改进措施和建议,认为对于大规模的槽式聚光集热器利用,因焦线运动造成的太阳辐射损失可不必考虑.     

SOLAR CONVERSION PARAMETERS OF GRADED BASE SILICON SOLAR CELLS

A simple model for the photovoltaic processes in a diffused base silicon solar cell is presented. The practical profiles of impurity concentration are taken into account by using the method of integration by piecewise exponential approximations. The realistic variation of mobility and built-in field are considered. Such parameters of solar conversion as short circuit current, open circuit voltage and conversion efficiency are computed. Results show that these parameters are are sensitive functions of the impurity distribution in the graded base and the recombination velocity at the surface of the diffused layer. The model holds promise of its application for parametric study and optimization of the solar cell configuration. © 1997 John Wiley & Sons, Ltd.     

The influence of defects on short circuit current density in p-i-n silicon solar cell

The admittance analysis method has been used to calculate the collection efficiency and the short circuit current density in a-Si:H p-i-n Solar cell, as a function of the thickness of i-layer. It is evident that the results of the short circuit current can be used to determine the optimal thickness of the i-layer of a cell, and it will be more accurate in comparison with previous studies using a constant generation rate or an empirical exponential function for the generation of charge carriers throughout the i-layer.