Solar & Wind Technology最新文献_第10页

Wake measurements behind a horizontal-axis 50 kW wind turbine 水平轴50千瓦风力涡轮机后面的尾流测量

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90085-G

H.D. Kambezidis, D.N. Asimakopoulos, C.G. Helmis

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引用次数: 15

Comparison of the solar-operated two-stage and single-stage LiBrH2O absorption cycles 太阳能驱动两级和单级LiBrH2O吸收循环的比较

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90021-S

Abdullah M. Al-Turki, Moustafa M. Elsayed

{"title":"Comparison of the solar-operated two-stage and single-stage LiBrH2O absorption cycles","authors":"Abdullah M. Al-Turki, Moustafa M. Elsayed","doi":"10.1016/0741-983X(90)90021-S","DOIUrl":"10.1016/0741-983X(90)90021-S","url":null,"abstract":"<div><p>Analysis of a solar operated two-stage LiBrH<sub>2</sub>O cycle is presented. The cycle has the advantages that it can operate at a higher ambient temperature and at a lower generator temperature than those required by the single stage cycle. The performance of the cycle is predicted and compared to the performance of the single stage cycle at various design conditions. Four design parameters are identified to control the performance of the cycle. These parameters are the heat sink temperature, the evaporator temperature, the generator temperature, and the intermediate pressure. Numerical correlations are developed to specify the minimum allowable sink temperature, the minimum and maximum allowable generator temperature and the coefficient of performance of both the single-stage and the two-stage cycles. By defining a system thermal ratio for the combined absorption machine and a flat plate collector, the performances of the integrated systems are evaluated and compared when using both cycles. Conditions at which the performance of the solar operated two-stage cycle is superior to that of the solar operated single stage cycle are defined.</p></div>","PeriodicalId":101171,"journal":{"name":"Solar & Wind Technology","volume":"7 4","pages":"Pages 355-366"},"PeriodicalIF":0.0,"publicationDate":"1990-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0741-983X(90)90021-S","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91420199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Wind and solar data for sizing small wind turbine and photovoltaic power plants 风能和太阳能数据，用于小型风力涡轮机和光伏发电厂的规模

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90013-R

W. Grainger

引用次数: 5

Small is usable: Lessons from alternative energy projects 小就是可用:替代能源项目的经验教训

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90018-W

S. Joseph, R. Burton

引用次数: 2

Realistic estimates of the beam radiation from global radiation measurements through an enhanced model for Athens, Greece 通过希腊雅典的增强模型对全球辐射测量得出的光束辐射的现实估计

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90102-8

Constantinos A. Balaras

{"title":"Realistic estimates of the beam radiation from global radiation measurements through an enhanced model for Athens, Greece","authors":"Constantinos A. Balaras","doi":"10.1016/0741-983X(90)90102-8","DOIUrl":"10.1016/0741-983X(90)90102-8","url":null,"abstract":"<div><p>Three years of hourly radiation data measured at the National Observatory of Athens, Greece (37.5°N, 23.5°E) are used to develop an empirical model for the prediction of the beam irradiation. The model is a correlation between three variables, namely the clearness index, <span><math><mtext>k</mtext><msub><mi></mi><mn><mtext>t</mtext></mn></msub></math></span> (defined as the ratio of global to extraterrestrial horizontal radiation), the atmospheric air-mass, <span><math><mtext>m</mtext></math></span>,and the beam transmittance, <span><math><mtext>τ</mtext><msub><mi></mi><mn><mtext>b</mtext></mn></msub></math></span> (defined as the ratio of beam normal to extraterrestrial normal radiation), and was developed by fitting an RMS locally weighted continuous surface to the available data. The proposed correlation can predict different values of (<span><math><mtext>τ</mtext><msub><mi></mi><mn><mtext>b</mtext></mn></msub></math></span>) for a given day, and over the year, for the same value of (<span><math><mtext>k</mtext><msub><mi></mi><mn><mtext>t</mtext></mn></msub></math></span>), which is what we observe from measured data.</p></div>","PeriodicalId":101171,"journal":{"name":"Solar & Wind Technology","volume":"7 2","pages":"Pages 313-320"},"PeriodicalIF":0.0,"publicationDate":"1990-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0741-983X(90)90102-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75254165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

A procedure for minimizing the photovoltaic pumping system in irrigation and leaching applications in the Baghdad area 在巴格达地区灌溉和浸出应用中尽量减少光伏泵系统的程序

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90081-C

Bassim E. Al-Sagir, A. Hasson

引用次数: 2

A procedure to obtain global solar radiation maps from sunshine duration for Pakistan 从巴基斯坦日照时数获取全球太阳辐射图的程序

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90093-H

Qamar-Uz-Zaman Chaudhary

引用次数: 7

Empirical model to estimate the global radiation in Bahrain by the knowledge of some astronomical parameters 利用一些天文参数的知识估算巴林全球辐射的经验模型

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90059-B

W.E. Alnaser, N.S. Awadalla

引用次数: 0

Effect of dust on transmittance of glazing materials for solar collectors under arid zone conditions of India 印度干旱区条件下粉尘对太阳能集热器玻璃材料透光率的影响

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90092-G

N.M. Nahar, Jagdish P. Gupta

引用次数: 101

Effects of edges on solar energy collection in small solar ponds 边缘对小型太阳能池太阳能收集的影响

Solar & Wind Technology Pub Date : 1990-01-01 DOI: 10.1016/0741-983X(90)90105-B

M.A. Hassab, O.A. El-Masry

引用次数: 1