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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Design and Thermal Performance Testing of a Heat Pipe Flat Plate Solar Collector

Greeley, Dennis N. 01 January 1977 (has links) (PDF)
This thesis investigates the use of heat pipes for removing heat from flat plate solar collectors and transferring the energy to air in a space heating system. Heat pipes are passive devices which are very efficient at transporting heat energy. They operate using a closed evaporation-condensation cycle. This thesis presents the fundamentals of flat plate collectors, heat pipes, and a set of parameters for evaluating a heat pipe flat collector. Also included are the results of this project and the recommendations for improvements.
152

Estudo sobre piscina solar / Study on solar pool

Brito, Jose Clet 23 March 2006 (has links)
Orientador: Kamal Abdel Radi Ismail / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-09T17:08:37Z (GMT). No. of bitstreams: 1 Brito_JoseClet_M.pdf: 4633715 bytes, checksum: 1c1eff1cb154ddf97b9f0996fa4289bf (MD5) Previous issue date: 2006 / Resumo: Neste trabalho apresentamos um estudo sobre piscina solar, como retentora de energia térmica, para futura transformação em energia elétrica, sendo esta constituída por 03 camadas de água salgada com gradientes de densidades diferentes e em ordem crescente de cima para baixo, fazendo com que obtivéssemos 03 temperaturas também em ordem crescente. Fizemos o seu monitoramento durante onze dias, e os dados obtidos nos ensaios permitiram uma análise das diferenças entre as temperaturas final e inicial, da zona de armazenamento, zona intermediária, zona de superfície e o rendimento ao longo dos onze dias no intervalo de tempo das 8:00h. às 17:00h., conforme mostra as tabelas 4.1 a 4.12. A apresentação dos resultados em forma de gráfico é muito importante, pois permite extrair com mais realidade os parâmetros que descrevem, de forma simples, o omportamento da piscina solar de gradiente salino. As variações de temperatura de cada zona, para melhor visualização gráfica, são apresentadas nos gráficos 4.1 a 4.11, sendo nas ordenadas as temperaturas médias e nas abscissas os tempos. E, no gráfico 4.12, o rendimento em função da temperatura média. Após a realização dos ensaios, os pontos foram plotados, gerando os gráficos 4.1 a 4.12. Utilizamos o valor médio diário da radiação solar incidente, como sendo 837,34W/m2, segundo dados da Tese de Mestrado de LOPES, (2004), para latitude de 2,55º em relação a linha do equador em São Luís do Maranhão e a potência total disponível de 164,41W. Os dados experimentais informam que a temperatura máxima da zona de armazenamento foi obtido no 2º ensaio, correspondendo a 45ºC e sua eficiência máxima de 13,09%, obtido no 5º ensaio, com intervalo de confiabilidade, respectivamente iguais a [4,26 ; 8,26]% e [5,16 ; 6,32]ºC, conforme demonstrativo nos apêndices: D.2.10.2 e D.5.8.2 / Abstract: In this work we present a study on solar swimming pool, as retainer of thermal energy, for future transformation in electric energy, being this consisting by 03 salty with gradients of different densities and orderly water layers increasing from top to bottom, making with that we also got 03 temperatures orderly increasing. We made its monitoramento during eleven days, and the data gotten in the assays had allowed an analysis of the differences between the temperatures final and initial, of the zone of storage, intermediate zone, zone of surface and the income to the long one of the eleven days in the interval of time of 8:00h. to 17:00h., as it shows to tables 4,1 the 4.12. The presentation of the results in graph form is very important, therefore it allows to extract with more reality the parameters that they describe, of simple form, the behavior of the solar swimming pool of saline gradient. The variations of temperature of each zone, for better graphical visualization, are presented in graphs 4,1 the 4,11, being in commanded the average temperatures and the abscissas the times. E, in the graph 4,12, the income in function of the average temperature. After the accomplishment of the assays, the points had been located, generating graphs 4,1 the 4.12. We use the daily average value of the incident solar radiation, as being 837,34W/m2, according to data of the Thesis of Mestrado of LOPES, (2004), for latitude of 2,55º in relation the line of the equator in São Luís of the Maranhão and the available total power of 164,41W. The experimental data inform that the maximum temperature of the storage zone was gotten in 2º assay, corresponding 45ºC and its maximum efficiency of 13,09%, gotten in 5º assay, with trustworthiness interval, respectively equal [ 4,26; 8,26]% and [ 5,16; 6,32]ºC, as demonstrative in the appendices: D.2.10.2 and D.5.8.2 / Mestrado / Instrumentação e Controle Industrial / Mestre em Engenharia Mecânica
153

A 300 MHZ solar receiving system.

January 1978 (has links)
Thesis (M.Phil.)--Chinese University of Hong Kong. / Bibliography: leaves 120-122.
154

Análise experimental do desempenho térmico de um sistema acoplado de coletores solares planos /

Pansanato, Cristiano. January 2016 (has links)
Orientador: Vicente Luiz Scalon / Banca: Ismael de Marchi Neto / Banca: Geraldo Luiz Palma / Resumo: A busca mundial for fontes de energia que garantam um crescimento sustentável tem marcado o século XXI. Nesse cenário, o Brasil é beneficiado, com diversas fontes de energias viáveis nas condições atuais e outras promissoras num cenário de médio e longo prazo. A utilização da energia solar convertida em energia térmica ou elétrica apresenta-se como uma destas alternativas. Explorar a energia solar de forma viável economicamente e melhorar a eficiência de captação e transformação são os grandes desafios que se apresentam. Neste contexto, este estudo se propôs a analisar experimentalmente o desempenho de um Sistema Acoplado, composto por coletores planos com e sem cobertura. O objetivo é reduzir o custo de implantação de um sistema de aquecimento, uma vez que o os coletores sem cobertura são mais baratos. Além disso, dependendo das características de implantação, é ainda possível aumentar a eficiência global do sistema através de um pré-aquecimento da água no coletor sem cobertura, aproveitando a maior eficiência térmica para temperaturas de operação próximas a do ambiente. Para estudo do Sistema Acoplado, um outro sistema composto apenas por coletores com cobertura foi montado e denominado Sistema Simples. Desta forma, com os dois aparatos montados e devidamente instrumentados foi possível obter resultados para as mesmas condições ambientais de teste. Assim, diversos esquemas de controle também puderam ser testados e analisados tanto na operação do Sistema Acoplado como do Sis... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The global search for energy sources that ensure sustainable growth has market the 21 st century. In this scenario, Brazil is benefited, with several viable sources of energy under current conditions and other promising sources in a medium and long-term scenario. The use of solar energy converted into thermal or electric ones presents itself as one of these alternatives. Using solar energy in a cost-effective way and improving the performance for capturing and transforming are the major challenges nowadays. In this content, this study proposed to analyze experimentally the performance of a Coupled System, composed by glazed and unglazed flat collectors. The purpose of this system is to reduce the installation costs of a heating system, since the unglazed collectors are less expensive. In addition, depending on its implementation chareacteristics, it is possible to increase the overall eficiency of the system by preheating the water in an unglazed collector, taking advantage of its higher thermal efficiency at nearby operating and ambient temperatures. For analysis of Coupled System, another system composed only of glazed collectors was assembled and denominated as Simple System. In this way, with the two devices mounted and instrumented some results can be obtained for the same environmental test conditions. Thus, several control schemes could also be tested and analyzed in the operation of both systems. Comparative results evaluating the output conditions, useful and stored energy and thermal performances are presented and compared for the systems / Mestre
155

The North House as Responsive Architecture: Designing for Interaction between Building, Inhabitant, and Environment

Barhydt, Lauren January 2010 (has links)
The North House is a proof-of-concept prefabricated solar-powered home designed for northern climates, and intended for the research and promotion of high-performance sustainable architecture. Led by faculty at the University of Waterloo, the project was undertaken by Team North a broad collaboration between faculty and students at the Universities of Waterloo, Ryerson and Simon Fraser. In October 2009, the North House prototype competed in the U.S. Department of Energy’s Solar Decathlon, where it placed fourth overall. The North House addresses the urgent environmental imperative to dramatically reduce energy consumed by the built environment. It does so, in part by employing two primary technological systems which make use of feedback and response mechanisms; the Distributed Responsive System of Skins (DReSS) reconfigures the envelope in response to changing weather conditions, while the Adaptive Living Interface System (ALIS) provides detailed performance feedback to the inhabitant, equipping them with informed control of their home. This thesis recognizes energy consumption as a socio-technical problem that implicates building inhabitants as much as buildings themselves. It also recognizes the particular potency of the ‘house’ as a building type that touches a broad population in a profoundly personal way; and is thus an apt testing ground for technologies that conserve energy, and those that teach occupants to do the same. With these ideas in mind, the thesis looks to Interactive Architecture - a practice that considers buildings and their inhabitants as an integrated system - as a promising conceptual framework for synthesizing the social and technical aspects of energy conservation in the home.
156

Simulation study for an absorption solar cooling system operated under Taiwan climate

Chiu, Yi-ying 22 August 2008 (has links)
In this thesis, solar energy is utilized as the driving energy for an absorption cooling system, and a TRNSYS computer code is employed to simulate the operation of the system under Taiwan climate. Climate data in TMY2 form for several major cities of Taiwan are input to the simulation program. Also system operating parameters of solar collector area and the size of the system storage are varied to study there effects on the system performance. This research provides computer simulation data for the monthly solar fraction (f) as well as the seasonal solar fraction (F) for the absorption solar cooling system operated under the climate of the major cities in Taiwan. The data can provide the design needs.
157

Assessment of the efficiency of solar radiation concentrating system.

Artur, Célia Domingas. January 2009 (has links)
A Solar Radiation Concentrating System for generation of high temperature heat for a solar oven was developed and evaluated at the University of KwaZulu-Natal, Westville Campus, Durban - South Africa. The system concentrates direct solar radiation on a small area receiver which absorbs the radiation and converts it into thermal energy that may be stored and used for several applications where food preparation and water pasteurization is the priority. The concentrator, area 2.2 m², is a half satellite communication dish covered with trapezoidal acrylic mirror tiles. The receiver/absorber is a spiral coil of blackened stainless steel pipe. Oil is circulated as heat transfer fluid. To determine the optimal dimension and position of the receiver, two experimental methods were used: (1) The tiles were scanned using a vertical, self adjusting laser beam to get a distribution of reflected radiation across the focal volume. (2) A thin, blackened stainless steel plate was placed at appropriate distances in the focal volume, and temperature distribution scanned using a temperature gun. The latter method proved to be the more useful. Results of the analysis of system performance showed that the system has the capability to produce high temperatures for domestic purposes. The efficiency of the system is about 35 %. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2009.
158

The North House as Responsive Architecture: Designing for Interaction between Building, Inhabitant, and Environment

Barhydt, Lauren January 2010 (has links)
The North House is a proof-of-concept prefabricated solar-powered home designed for northern climates, and intended for the research and promotion of high-performance sustainable architecture. Led by faculty at the University of Waterloo, the project was undertaken by Team North a broad collaboration between faculty and students at the Universities of Waterloo, Ryerson and Simon Fraser. In October 2009, the North House prototype competed in the U.S. Department of Energy’s Solar Decathlon, where it placed fourth overall. The North House addresses the urgent environmental imperative to dramatically reduce energy consumed by the built environment. It does so, in part by employing two primary technological systems which make use of feedback and response mechanisms; the Distributed Responsive System of Skins (DReSS) reconfigures the envelope in response to changing weather conditions, while the Adaptive Living Interface System (ALIS) provides detailed performance feedback to the inhabitant, equipping them with informed control of their home. This thesis recognizes energy consumption as a socio-technical problem that implicates building inhabitants as much as buildings themselves. It also recognizes the particular potency of the ‘house’ as a building type that touches a broad population in a profoundly personal way; and is thus an apt testing ground for technologies that conserve energy, and those that teach occupants to do the same. With these ideas in mind, the thesis looks to Interactive Architecture - a practice that considers buildings and their inhabitants as an integrated system - as a promising conceptual framework for synthesizing the social and technical aspects of energy conservation in the home.
159

The development and testing of a solar wall air preheater for livestock and poultry buildings /

Andreadakis, Stavros. January 1981 (has links)
No description available.
160

Structure and energy transport of the solar convection zone

Armstrong, James D, 1970 January 2004 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 134-139). / Also available by subscription via World Wide Web / xvi, 139 leaves, bound ill. 29 cm

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