• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 249
  • 61
  • 20
  • 16
  • 8
  • 8
  • 5
  • 4
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 391
  • 213
  • 123
  • 115
  • 99
  • 93
  • 69
  • 69
  • 61
  • 61
  • 54
  • 52
  • 52
  • 52
  • 51
  • 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

Využití energetického posudku při návrhu domu s téměř nulovou spotřebou energie / Use of energy assessment for the design of the building with almost zero energy consumption

Horák, Jakub January 2019 (has links)
The diploma thesis deals with the design of nearly zero energy buildings. It focuses primarily on optimizing the thermal insulation thickness at a cost-optimal level. Based on energy consumption analysis, three heat sources are selected and then evaluated using an energy assessment. The building is evaluated in terms of energy, economic and environmental.
152

Parní kotel na biomasu menších výkonů / Steam Grate Biomass Boiler

Suchánková, Lenka January 2021 (has links)
The master's thesis describes the design of the steam boiler, which burns biomass with heat output of 6 MW. The required parameters of the steam are a temperature of 300 °C and a pressure of 2,5 MPa. The thesis is gradually devoted to stoichiometric calculations through heat losses and boiler efficiency, to the design of the combustion chambre, heat exchangers and pressure losses. Part of the thesis is drawing documentation of the boiler.
153

Vytápění bytového komplexu / Heating of the Apartment Complex

Míková, Šárka January 2015 (has links)
This diploma thesis focuses on the design of heating and hot water reservoir in an apartment complex. For three variants of heat sources (gas condensing boiler, heat pump and electric boiler) is evaluated their economic profitability for heating and hot water heating. For the best selected heat sources is drawn up the technical solution of heating in the apartment complex.
154

Vytápění polyfunkčního objektu / Heating of the Multifunctional Building

Konečný, Ladislav January 2015 (has links)
This diploma thesis proposes the heating system and ventilation in mixed-use building. The building is located in Uherské Hradiště. The object of this work is the selection of appropriate variants of two heat sources (gas boilers and solid fuel boiler). The project is focus on design of the heating system chosen mode of heating, which are gas boilers and the concept of forced ventilation. The theoretical part is focused on the regulation.
155

Návrh vytápění budovy / Design of heating of the building

Dittrichová, Zuzana January 2016 (has links)
The aim of this diploma thesis is to find a solution of heating system, a hot water preparation and a subsequent design of the heat source for the apartment building. The project consists of a calculation of heat losses, a design of radiators, a dimensioning of pipes and a design of two options of the heat source for heating and hot water preparation. The first option of the heat source I chose a pellet boiler and the second option is an electric boiler with solar collectors for the preparation of hot water. The introductory part deals with analysis of this object and emission limits of heat source using different fuels.
156

Roštový kotel na spalování biomasy / Grate Boiler for Biomass Combustion

Szabó, Gergely January 2016 (has links)
The thesis deals with the design of a grate steam boiler which has natural circulation and is determined for combustion of wood chips. The boiler has a capacity of 45 t/h and produces superheated steam with the output parameters of 3,5 MPa and 450 °C at the 125 °C feed water temperature. Stoichiometric calculations and the flue gases enthalpy calculations are based on the composition of the specified fuel. The efficiency and fuel consumption of the boiler is also determined. The thesis mainly focuses on the thermal calculation and geometric design of the individual heat transfer surfaces of the boiler. The drawing documentation of the steam boiler is available in the attachment of the thesis.
157

Provozní účinnost plynových kotlů / Operational efficiency of gas boilers

Marčiš, Šimon January 2022 (has links)
This master’s thesis elaborates a design of water heating and heating system for a building of a rehabilitation center in Horný Hričov. The theoretical section describes operational efficiency of gas boilers and associated calculation methods. The experimental section covers measurements of condensing gas boiler at various temperatures of heating water conducted in university laboratory. Operational efficiency was then calculated using indirect method based on the measurement results. Subsequently, calculated values and values measured by an operational efficiency analyzer were compared. The comparison revealed minor deviations in operational efficiency values and different values of condensing heat utilization between the calculations and the analyzer results. The analytical section of the thesis consists of complex designs of two versions of the heating system and the water heating. The first design version uses condensing gas boilers as a heat source while the second version uses a water-air heat pump instead. The project section of the thesis is executed in the scope for a building permit and consists of a technical report and a design documentation.
158

Akumulační zásobníky v otopných systémech / Accumulation tanks in heating systems

Železná, Karolína Unknown Date (has links)
The subject of the diploma thesis is accumulation tanks in heating systems. The first part introduces the topic of thermal energy storage and types of accumulation tanks. The second part describes two specific options of heating the building of the boarding house and the restaurant with the use of storage tanks in the heating system. A gas condensing boiler is designed as a heat source in one variant and a pellet boiler in the other variant. The third part deals with experimental measurements, in which the accumulation tank with the installation for better stratification of hot water and the accumulation tank without the installation are compared.
159

Проблемы технического перевооружения систем теплоснабжения с целью повышения их энергетической эффективности : магистерская диссертация / Problems of reconstruction of heat supply systems in order to improve their energy efficiency

Гордиенко, Н. С., Gordienko, N. S. January 2018 (has links)
В выпускной квалификационной работе описываются основные пути реконструкции систем теплоснабжения, позволяющие добиться значительного повышения их энергоэффективности, а именно переход котельной на альтернативное топливо с целью повышения энергоэффективности, снижения экономических и экологических потерь. Целью работы является поиск и формулирование основных проблем реконструкции систем теплоснабжения, развитие технологического процесса перевода котельной на альтернативное топливо, проведение энергетического и экономического обоснования предлагаемой замены. Были изучены отечественные и зарубежные публикации по проблемам реконструкции систем теплоснабжения для повышения их энергоэффективности. Приведено обоснование необходимости перевода котельной на альтернативное и экологически чистое топливо, на основе оценки основного и вспомогательного оборудования котельной, а также экологического благополучия территории, прилегающей к котельной. Разработан технологический процесс перевода котельной на альтернативное и экологически безопасное топливо, выявлена и доказана необходимость модернизации оборудования для использования альтернативного топлива. Были определены существующие методы модернизации котла, работающего на угле для альтернативного и экологически чистого топлива. Выполнено экономическое обоснование предлагаемой замены. / This final qualifying work describes the main ways of reconstruction of heat supply systems, allowing achieving a significant increase in the energy efficiency of these systems, namely the transfer of the boiler to alternative fuel in order to improve energy efficiency, reduce economic and environmental losses. The purpose of the work is to consider and formulate the main problems of reconstruction of heat supply systems, development of the technological process of transferring the boiler house to alternative fuel, implementation of energy and economic justification of the proposed replacement. Domestic and foreign publications on the problems of reconstruction of heat supply systems in order to improve their energy efficiency were studied. The substantiation and relevance of the transfer of the boiler house to alternative and environmentally friendly fuel was discussed, for which the assessment of the main and auxiliary equipment of the boiler house, as well as the ecological well-being of the territory adjacent to the boiler house. The technological process of transfer of a boiler room to alternative and environmentally friendly fuel was developed, need of modernization of the equipment for use of pellet fuel is revealed and proved. The existing methods of modernization of the boiler unit operating on coal for alternative and environmentally friendly fuel were identified. Economic justification of the proposed replacement was done.
160

Physical and numerical modelling of flow pattern and combustion process in pulverized fuel fired boiler

Baranski, Jacek January 2002 (has links)
<p>This licentiate thesis describes development of modellingtools, experimental physical modelling and numerical modellingto simulate real combustion processes for advanced industrialutility boiler before and after retrofit.</p><p>The work presents extended study about formation,destruction and control of pollutants, especially NOx, whichoccur during combustion process.</p><p>The main aim of this work is to improve mixing process incombustion chamber. To do this, the optimization of placementand direction of additional air and fuel nozzles, the physicalmodelling technique is used. By using that method, it ispossible to obtain qualitative information about processes,which occur in the real boiler. The numerical simulationsverify the results from physical modelling, because duringmathematical modelling quantitative informations about flow andmixing patterns, temperature field, species concentration areobtained.</p><p>Two 3D cases, before and after retrofit, of pulverized fuelfired boiler at 125 MW output thermal power are simulated. Theunstructured mesh technique is also used to discretize theboiler. The number of grid was 427 656 before retrofit and 513362 after retrofit. The comparisons of results of numericalsimulation before and after retrofit are presented. The resultsfrom physical modelling and numerical simulation are alsoshown.</p><p>Results present that nozzles of additional air and fuel givea considerably better mixing process, uniform temperature fieldand CO2 mass fraction. The whole combustion chamber worksalmost as a "well stirred reactor", while upper part of boilerworks as a "plug flow reactor".</p><p>Differences between from measured of temperatures andpredicted temperatures are not too big, the maximum differenceis about 100 K. It seems, that calculated temperatures showgood agreement with measurement data.</p><p>The results illuminate the potential of physical andnumerical modelling methods as promising tools to deal with thecomplicated combustion processes, even for practicalapplication in the industry.</p><p><b>Keywords:</b>air staging, fuel staging, boiler, furnace,computational fluid dynamics, numerical simulation, pollutants,physical modeling, pulverized fuel combustion.</p>

Page generated in 0.023 seconds