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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.
101

Denni osvětlení a solární tepelná zátěž budov / Day lighting and solar heat load of buildings

Vyhlídalová, Karolína January 2013 (has links)
This master´s thesis is about searching for a connection between solar illumination and solar irradiance. The task is attempt to find out if it is possible to use one factor in order to determine the other one. Part of this thesis deals with cooling of virtual building.
102

Uplatnění energie obnovitelných zdrojů v budovách / The application of renewable energy in buildings

Panovec, Jan January 2015 (has links)
The aim of this diploma thesis is to understand the functioning of heating and cooling systems in an administrative building built in passive standard using a renewable energy source. The thesis includes theoretical findings of heat pumps and designing the heating systems. The experimental part contains an analysis of working of heating and cooling systems in selected rooms in assigned building, which includes an experimental measurement of selected quantities and a thermographic measurement. In the last part of the thesis a comparison of measured and simulated values using simulation software was done.
103

Solární chladicí systém / Solar cooling system

Klusák, Jan January 2009 (has links)
The work is focused on the issue of cold production using absorbent circulation driven by thermal energy solar collectors recovered. The work can be divided into several main parts. In the first part of this work is given an overview of the possible principles of solar cooling system. In the next section followed by a description of the principle of absorption cycles. In the practical part is solved design proposal absorption refrigeration units with a cooling power of 6 kW. This is followed by a proposal to link solar cooling system with the absorption unit. Final section is made of basic technical-economic comparison of solar refrigeration unit with the compressor refrigeration units.
104

Technologie výroby plastové pružné spony / Production technology flexible plastic clip

Mikulenka, Martin January 2011 (has links)
Currently, the plastics industry has a wide range of applications due to the possibility of a fully automated process or through increased production efficiencies. The reason for this choice of the thesis was to understand the whole issue of plastic injection molding process. The specified component is used to atach the sail, which serves to protect workers in the welding sector. A specified number of the series is 350 000. The work includes a theoretical problem of injection molding process, selection of technology, material selection and design of mold. An integral part of every design mold is a simulation of injection, which is also included. In conclusion of thesis is the calculation of the various stages of production and operation of the injection mold.
105

Výroba krytu kola automobilu / Production of car wheel cover

Říha, Pavel January 2012 (has links)
The Master’s thesis is concentrated on a thermoplastic injection technology and in particular on heat balance of tool. In the theoretical part, literary study, is shortly described actual knowledge in these branches. In the practical part is solved the design of tool for production of the specific plastic part. This thesis insists on the proposal and selection of applicable cooling system in the tool and on optimization of the technology parameters of injection proces. Those proposals are evaluated by simulation software Cadmould 3D-F. In the end of this thesis is performed the economic analysis of plastic part production costs.
106

Třírotorový lopatkový stroj pro klimatizační systém / 3-wheel air cycle machine

Vrána, Jan January 2012 (has links)
For air cooling in aircrafts is used an air cycle machine. Recently, there is focusing on incresing efficiency of air cycle and due this are added another rotors. Design of machine with three rotors is performed in this thesis.
107

Análise do efeito da convecção forçada para resfriamento de sistema térmico fotovoltaico /

Reis, Renato Candido January 2020 (has links)
Orientador: Elaine Maria Cardoso / Resumo: O presente trabalho consistiu na análise teórica e experimental de um sistema híbrido PVT - fotovoltaico/térmico. Este consiste de um painel fotovoltaico (PV), com sistema de rastreamento, para aproveitar a radiação solar direta e difusa, e de um sistema d e resfriamento por convecção forçada acoplado, permitindo gerar eletricidade e calor em um único processo além de reduzir a temperatura de operação de um painel solar fotovoltaico comercial e, assim, melhorar sua eficiência energética. O módulo PV está instalado na região noroeste do estado de São Paulo. O conjunto experimental possui um sistema de rastreamento solar azimutal de eixo simples; a tensão e a corrente de saída do painel foram medidas para quantificar a potência produzida levando em consideração diferentes condições de operação. Todos os testes foram realizados in loco usando um painel fotovoltaico comercial, sempre levando em consideração as condições meteorológicas do dia. O rastreamento solar aumenta em 45,5% a energia gerada para um dia do mês de junho em relação a um sistema fixo. O painel fotovoltaico com a parte posterior isolada termicamente opera em condições 15 °C a 20 °C mais quente que um painel não isolado, o que implica em perdas energéticas da ordem de 7,6%. O trocador de calor tipo serpentina, com uso de água deionizada, não mostrou desempenho satisfatório ao resfriar o módulo fotovoltaico devido à significativa resistência térmica de contato com a face posterior do módulo. A análise teórica apre... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work consisted of a theoretical and experimental analysis of a hybrid PVT – photovoltaic/thermal system. This system consisted of a photovoltaic (PV) panel with a solar tracking system to take advantage of direct and diffuse solar radiation and a forced convection cooling system. This allows the generation of electricity and useful heat in a single process in addition to reducing the operating temperature of a commercial photovoltaic solar panel and thus improves its energy efficiency. The PV module is installed in the northwest region of the state of São Paulo. The experimental apparatus had a single axis, azimuth solar tracking system; the output voltage and current of the panel were measured to quantify the power produced taking into account different operating conditions. All tests were carried out in loco using a commercial photovoltaic panel, always taking into account the weather conditions of the day. Solar tracking increases the energy generated by one day of the month by 45.5% compared to a fixed system. The temperature of the module with a thermally insulated back sheet was 15° C to 20° C hotter than a non-insulated panel, which implies energy losses of the order of 7.6%. The serpentine type heat exchanger, using deionized water, did not show satisfactory performance when cooling the photovoltaic module due to the significant thermal resistance of contact with the rear face of the module. Theoretical analysis showed errors of less than 10% compared to t... (Complete abstract click electronic access below) / Mestre
108

Aktuelle Themen der Reaktorsicherheitsforschung in Deutschland

Weiß, Frank-Peter January 2006 (has links)
Die Veranstaltung widmete sich mit der Borverdünnung in Druckwasserreaktoren bzw. mit der Verstopfung der Sumpfansaugsiebe durch freigesetztes Isolationsmaterial schwerpunktmäßig zwei Themen der Reaktorsicherheit, die auch in aktuellen Aufsichtsverfahren eine Rolle spielen. Eingebettet in den internationalen Kontext wollten die Veranstalter die sicherheitstechnische Bedeutung dieser Themen für die deutschen Anlagen beleuchten und die Auswirkungen auf die zu erbringenden Sicherheitsnachweise und den Anlagenbetrieb darstellen. Dabei kamen Gutachter, Vertreter der Forschung, Hersteller und Betreiber gleichermaßen zu Wort. Der Fachtag sollte den Teilnehmern aber insbesondere vermitteln, welche Beiträge die privat und öffentlich finanzierte Reaktorsicherheitsforschung zur Aufklärung der jeweiligen Ereignisabläufe und ihrer sicherheitstechnischen Bedeutung geleistet hat. In diesem Forschungskontext spielen, auch international, die Methoden der so genannten Computational Fluid Dynamics (CFD) eine zunehmende Rolle. Deshalb widmete sich eine Sitzung den Grundlagen, Möglichkeiten und Grenzen von CFD-Methoden. Dabei wurden u.a. Anwendungen zur Borvermischung und zum Verhalten von Mineralwolle im Sumpf präsentiert.
109

Further study of Life Cycle Assessment of a high density data center cooling system – Teliasonera’s “Green Room” concept : Identification of improvement possibilities using Life Cycle Assessment (LCA) and discussion about the effect of the choice of Life Cycle Impact Assessment (LCIA) methods on the results

Wang, Shan January 2013 (has links)
The growing industry of Information and Communication Technology requires higher computing capacity of data centers. The air conditioning in data centers is a key to assure a sustainable computing environment. However, the traditional cooling systems cost large environmental footprints especially on energy consumption and greenhouse gas emissions. As a result, a green innovation of data center cooling solutions is taking place. The telecommunication company Teliasonera is developing a high density data center cooling system - the “Green Room” and has been studying the environmental performance of this system using a Life Cycle approach. As an extension of the previous study, more aspects of the project i.e. the location of the data center, life span, alternative cooling solutions, energy recovery possibilities and uncertainty analysis is explored using Life Cycle Assessment (LCA) methodology. The comparison of locations of the Green Room indicates that the local temperature and electricity production sources are essential factors for the environmental performance of the Green Room. The analysis of the Green Room’s life span reveals that the utilization phase may not always cause the most significant impact during the whole life cycle of the Green Room. If the life span changes, the manufacture phase may predominate the life cycle of the Green Room. The comparative result of alternative cooling technologies addresses that utilizing “natural coolant” (e.g. geo cooling) is a key for sustainable cooling innovation as it could significantly reduce the environmental footprint of the cooling system. Besides, heating a single building (partly) by the waste heat generated from the Green Room could save 30% of cumulative energy input and could reduce more than half of the total environmental impact. Additionally, results uncertainties caused by the choice of different LCIA methods are discussed in the end of the study. / Teliasonera's Green Room concept
110

Further study of Life Cycle Assessment of a high density data center cooling system – Teliasonera’s “Green Room” concept : Identification of improvement possibilities using Life Cycle Assessment (LCA) and discussion about the effect of the choice of Life Cycle Impact Assessment (LCIA) methods on the results

Wang, Shan January 2013 (has links)
The growing industry of Information and Communication Technology requires higher computing capacity of data centers. The air conditioning in data centers is a key to assure a sustainable computing environment. However, the traditional cooling systems cost large environmental footprints especially on energy consumption and greenhouse gas emissions. As a result, a green innovation of data center cooling solutions is taking place. The telecommunication company Teliasonera is developing a high density data center cooling system - the “Green Room” and has been studying the environmental performance of this system using a Life Cycle approach. As an extension of the previous study, more aspects of the project i.e. the location of the data center, life span, alternative cooling solutions, energy recovery possibilities and uncertainty analysis is explored using Life Cycle Assessment (LCA) methodology. The comparison of locations of the Green Room indicates that the local temperature and electricity production sources are essential factors for the environmental performance of the Green Room. The analysis of the Green Room’s life span reveals that the utilization phase may not always cause the most significant impact during the whole life cycle of the Green Room. If the life span changes, the manufacture phase may predominate the life cycle of the Green Room. The comparative result of alternative cooling technologies addresses that utilizing “natural coolant” (e.g. geo cooling) is a key for sustainable cooling innovation as it could significantly reduce the environmental footprint of the cooling system. Besides, heating a single building (partly) by the waste heat generated from the Green Room could save 30% of cumulative energy input and could reduce more than half of the total environmental impact. Additionally, results uncertainties caused by the choice of different LCIA methods are discussed in the end of the study. / Teliasonera's Green Room concept

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