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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.
201

Natural gas stability and thermal history of the Arbuckle Reservoir, Western Arkoma Basin /

Tabibian, Mahmoud. January 1993 (has links)
Thesis (Ph.D.)--University of Tulsa, 1993. / Includes bibliographical references (leaves 254-269).
202

Computer modelling and simulation of geothermal heat pump and ground-coupled liquid desiccant air conditioning systems in sub-tropical regions

Lee, Chun-kwong. January 2008 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 177-192) Also available in print.
203

The economic analysis of geothermal/absorption cooling of a hospital: Case study of Dokuz Eylül University research and application hospital /Mete Altın; thesis advisor Gülden Gökçen.

Altın, Mete. Gökçen, Gülden. January 2006 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2006. / Keywords: Economic analysis, absorption cooling. Includes bibliographical references (leaves. 88-90).
204

Renewable energy in Montana system applications and technlogy /

Corr, Mandi Lee. January 2008 (has links) (PDF)
Thesis (M.A.) -- University of Montana, 2008. / Title from author supplied metadata. Description based on contents viewed on July 15, 2009. Includes bibliographical references.
205

Γεωλογική - υδρογεωλογική διερεύνηση της ευρύτερης περιοχής του βορείου τμήματος της λεκάνης της Ηλείας και χρήση μεθόδων υδροχημικής - ισοτοπικής ανάλυσης για τον προσδιορισμό της ζώνης τροφοδοσίας της θερμομεταλλικής πηγής Κυλλήνης

Πυργάκη, Αναστασία 19 April 2010 (has links)
Η περιοχή μελέτης ανήκει στη ΒΔ Πελοπόννησο, εκτείνεται στο βόρειο τμήμα του νομού Ηλείας και στο νοτιοανατολικό τμήμα του νομού Αχαΐας, χαρακτηρίζεται από την εμφάνιση υπόθερμων θερμομεταλλικών πηγών, καταλαμβάνει έκταση περίπου 1500 Km2 και αναπτύσσεται σε διεύθυνση Α-Δ από τον Ερύμανθο ως τις δυτικές ακτές. Η περιοχή μελέτης οριοθετήθηκε με κύριο κριτήριο τη γεωλογική δομή και τη νεοτεκτονική εξέλιξη της ΒΔ Πελοποννήσου αλλά και τις υδρογεωλογικές συνθήκες, προκειμένου να ερευνηθεί η προέλευση της θερμομεταλλικής υδροφορίας της πηγής των Λουτρών Κυλλήνης καθώς και η σχέση της με τις υπόλοιπες θερμομεταλλικές εμφανίσεις της περιοχής μελέτης. Η αναζήτηση της ζώνης τροφοδοσίας της θερμομεταλλικής πηγής Κυλλήνης προέκυψε από την γεωλογική – υδρογεωλογική έρευνα στην περιοχή Λουτρών Κυλλήνης, σε συνδυασμό με τα στοιχεία υφιστάμενων μελετών, από όπου προκύπτει: 1) η σχέση του νερού της πηγής Κυλλήνης, μετεωρικής προέλευσης, με τους βαθύτερους υδροφορείς μέσω των ενεργών νεοδιαπειρικών ρηγμάτων, η δε ανάπτυξη της θερμομεταλλικής υδροφορίας εντοπίζεται σε μία ζώνη με γενική διεύθυνση Α-Δ, 2) η παροχή, η θερμοκρασία και η μεταλλικότητα της πηγής παρουσιάζει διαχρονικά σταθερότητα και το θερμό θειούχο νερό δημιουργείται εντός ασβεστολιθικών πετρωμάτων, που βρίσκονται σε μεγαλύτερες αποστάσεις σε σχέση με αυτά της περιοχής Κάστρου Κυλλήνης. Από τη γεωλογική, τεκτονική και υδρογεωλογική διερεύνηση της περιοχής μελέτης προκύπτει: 1) η δυνατότητα τόσο της κατακόρυφης όσο και της οριζόντιας σε βάθος κίνησης του νερού μέσω του σύνθετου τεκτονικού ιστού της περιοχής, 2) η από το κεντρικό τμήμα της μεταλπικής λεκάνης πιθανή επικοινωνία των θερμομεταλλικών νερών μέσα από τις ζώνες των ρηγμάτων της περιοχής και 3) η πιθανή τροφοδοσία αυτών από το καρστικό σύστημα των ανθρακικών σχηματισμών του Ερύμανθου. Από την υδροχημική – ισοτοπική έρευνα των νερών του δικτύου δειγματοληψίας που περιελάμβανε νερά πηγών και γεωτρήσεων τόσο γλυκού νερού όσο και θερμομεταλλικού, με διασπορά στην έκταση της περιοχής μελέτης, μελετήθηκε ο υδροχημικός χαρακτήρας των υπόγειων νερών και η ισοτοπική τους σύσταση. Συσχετίζοντας τις γεωλογικές – υδρογεωλογικές συνθήκες των εμφανίσεων της θερμομεταλλικής υδροφορίας στη περιοχή μελέτης με τα υδροχημικά τους χαρακτηριστικά (δηλαδή τους υδροχημικούς δείκτες, τη χημική ταξινόμηση, το χαρακτηρισμό του τύπου των νερών), σε συνάρτηση με την ισοτοπική τους σύσταση, επιβεβαιώνεται η κοινή προέλευση των γεωθερμικών ρευστών των διαφορετικών πηγών καθώς και η συμμετοχή του νερού των καρστικών υδροφορέων της ζώνης Πίνδου στη τροφοδοσία τους. Οι διαφορές που παρατηρούνται ωστόσο στη σύσταση στο σημείο εκροής (δηλαδή διαφορετική θερμοκρασία και αλατότητα, διαφορά στην παροχή, καθώς και μικρές διαφορές σε συγκεντρώσεις ιόντων), μαρτυρούν τη διαφορετική πορεία του γεωθερμικού ρευστού από το γεωθερμικό ταμιευτήρα ως την επιφάνεια. / The region of study belongs to the SW Peloponnese, extends in the northern department of the province of Ilia and in the SE department of the province of Achaia, is characterized by the appearance of hypothermal geothermal-mineral springs, occupies extent approximately 1500 Km2 and is developed in direction E-W from Mount Erymanthos to the sea. The region of study was delimited with main criterion the geological structure and the neotectonic development of SW Peloponnese but also the hydrogeological circumstances so that the origin of the geothermal aquifer of the spring of Killini’s Baths as well as its relation with the remainder of the geothermal-mineral appearances in the region of study are searched. The inquiry of the recharge zone of the geothermal spring of Killini resulted from the geological – hydrogeological research in the region of Killini’s Baths in combination with the elements of pre-existing studies, from where it results: 1) the relation of the water in Killini’s spring, whose origin is meteoric, with the deeper aquifers via the active diapir faults as well as the growth of the geothermal aquifer which is located in an area with general direction Ε-W, 2) the supply, the temperature and the minerality of the spring present stability through the years and the hot, sulphurous water is created on the inside of limestone rocks, that are found in bigger distances in relation to those of the region of Killini’s Castle. From geological, tectonics and hydrogeological investigation in the region of study, it results: 1) the possibility of both vertical and horizontal in-depth water movement via the complex tectonic web of the region, 2) the likely communication of geothermal-mineral via the fault zones of the region in the central department of the post alpine basin 3) probable recharge of the geothermal-mineral from the karsts system of Mount Erymanthos carbonic formations. The hydrochemical character of the underground waters and their isotopic composition were studied, with dissemination in the extent of study region , by the hydrochemical-isotopic research of waters of network of sampling that included waters of springs and drillings both sweet and geothermal-mineral. The common origin of geothermal fluid coming from different springs as well as the participation of the karst aquifer of the zone of Mount Erymanthos in their recharge were confirmed by connecting the geological – hydrogeological conditions of the geothermal – mineral aquifer appearances in the region of study with their hydrochemical characteristics (hydrochemical indicators, the chemical classification, the characterization of water type) and in combination with their isotopic composition. However, the differences that are observed in the characteristics at the point of flow (different temperature and salinity, difference in the supply as well as small differences in concentration if ions), testify the different course of geothermal fluid from the geothermal basin to the surface.
206

Θερμομεταλλικά νερά της νήσου Λέσβου

Βιολάντη, Μαρία 06 December 2013 (has links)
Στη παρούσα πτυχιακή εργασία παρουσιάζονται στοιχεία σχετικά με τα θερμομεταλλικά νερά της Νήσου Λέσβου. Πραγματοποιήθηκαν υδροχημικές αναλύσεις με δείγματα από τις πηγές: Πολιχνίτου, Αγίου Ιωάννη Λισβορίου, Πέτρας (από γεώτρηση), Λεπέτυμνου, Εφταλούς, Θέρμων Κόλπου Γέρας, Λουτρόπολης Θερμής. Η ηφαιστειακή δραστηριότητα στην περιοχή του Αιγαίου, κατά την Τριτογενή και Τεταρτογενή περίοδο, είχε ως αποτέλεσμα την εμφάνιση πολλών θερμοπηγών στο νησί, οι οποίες παρουσιάζουν ενδιαφέρον τόσο από θεραπευτική όσο και από γεωλογική άποψη. Οι πηγές αυτές, που αποτελούν σημαντικό φυσικό πόρο της περιοχής, προέρχονται από μετεωρικά νερά (νερά βροχής) που έχουν κατεισδύσει σε μεγάλο βάθος. Τα νερά αυτά θερμαίνονται επαγωγικά και κατόπιν ανεβαίνουν προς την επιφάνεια µε τη βοήθεια της ατμιδικής ενέργειας. Επίσης, συμμετοχή στη σύσταση του νερού των θερμοπηγών πιθανόν να έχει και το θαλασσινό νερό. / --
207

Aproveitamento de fontes alternativas para redução do consumo de energia elétrica e reflexos nos seus custos / Utilization of alternative sources for reducing power consumption and its consequences in costs

Dutra, Adriane 17 September 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Residential consumption accounts for around one third of total energy consumed in Brazil. The electric shower is the main component of this consumption, along with air conditioning. Hence, much research has been conducted in order to reduce the consumption of this sector and the use of alternative energy sources. Among these include mainly solar and geothermal. This thesis aims to establish the bases for assessing the structure of household consumption in order to develop a methodology to reduce power consumption. A prototype was developed in the CEEMA experimental area (UFSM), with the assembly of two prototypes: a solar collector associated with the two types of heating, electric and gas, the other, a geothermal prototype system for surface environments conditioning and pre-heating water. A retrospective on the main alternative to replace the traditional electric shower and air conditioner was conducted as well as ways to reduce heating losses. Practical data were automatically collected to demonstrate the energy efficiency of the studied environment which can be residential, seeking to reduce power consumption and thermal energy and the reflections in the final cost of electric power. The use of thermal sources seen in this thesis was used to demonstrate viable and tangible results in reducing energy consumption and electric power. These results were extrapolated to the region south of the country indicating the possibility of reducing the use of primary energy and, consequently, the conservation of the environment. / O consumo residencial representa em torno de um terço do total de energia consumida no Brasil. O chuveiro elétrico é o principal componente deste consumo, juntamente com o ar condicionado. Assim, muitas pesquisas têm sido realizadas, visando à diminuição do consumo deste setor e o aproveitamento de fontes de energia alternativas. Dentre as quais se destacam a energia solar e geotérmica. Esta dissertação tem como objetivo estabelecer as bases da avaliação da estrutura de consumo residencial visando à obtenção de uma metodologia para reduzir o consumo de energia elétrica. Foi desenvolvido um protótipo habitável de residência no Campus Experimental do CEEMA (UFSM), com a montagem de dois protótipos: um com coletor solar associado a dois tipos de aquecimento, elétrico e a gás, outro, um protótipo de sistema geotérmico superficial para condicionamento de ambientes e pré-aquecimento de água. Foi feita uma retrospectiva nas principais alternativas para a substituição do chuveiro elétrico tradicional e do condicionador de ar bem como das formas de redução de perdas para aquecimento. Dados práticos foram coletados automaticamente para demonstrar a eficientização energética do ambiente estudado que pode ser residencial , buscando a redução do consumo de potência e energia térmica e os reflexos nos custos finais com energia elétrica. O aproveitamento das fontes térmicas vistas nessa dissertação foi utilizado para demonstrar as alternativas viáveis e resultados concretos na redução do consumo e potência elétrica. Estes resultados foram extrapolados para a região Sul do país indicando a possibilidade de diminuição da utilização primária de energia e, por conseqüência, a conservação do meio ambiente.
208

Investigation of the energy saving potential for an office building complex : A study on the viability of an on-site combined heat- and power supply system

Eriksson, Douglas January 2018 (has links)
The building stock in the European Union accounts for over 40% of final energy use, where the usage of non-residential buildings may be up to 40% higher than the residential sector. Improving building energy efficiency across all categories of buildings is one key goal of the European energy policies, made prominent by the Climate and Energy package, Energy Performance of Building Directive (EPBD) and Energy Efficiency Directive (EED). In this study, a simulation model of an office-building complex utilizing district heating was created using transient simulation software TRNSYS. The model was validated using consumption data provided by the facility owner, after which an investigation of the energy saving potential along with the economic viability of adapting a new heat- and power supply system was conducted. The system designs were comprised of a geothermal energy system in combination with a PV-system and electricity storage. It was concluded that the systems were sufficient in maintaining an adequate indoor climate. Furthermore, the investments were ascertained as profitable and resulted in a decreased building specific energy demand.
209

Les eaux géothermiques du gisement Khankala ˸ formation, utilisation, prévisions / Geothermal waters of the Khankala deposit ˸ formation, use, forecasts

Farkhutdinov, Anvar 23 December 2016 (has links)
Récemment, une attention considérable a été accordée dans le monde à l'utilisation des sources d'énergie renouvelables. Parmi celles-ci, les eaux géothermales sont d'une grande importance en raison de la sécurité écologique et de l'efficacité économique de leur utilisation. La Russie possède un fort potentiel de ressources confirmées en eau géothermale, mais aujourd'hui, seule une faible proportion est utilisée. L'un des territoires les plus prometteurs pour les eaux géothermales est la République Tchétchène, qui se trouve à la 3ème place parmi les régions russes pour les réserves opérationnelles approuvées de gisements d'eaux géothermales, parmi lesquelles la plus importante est le gisement de Khankala.Le développement durable des ressources en eaux géothermales exige une approche intégrée. L'analyse géostatistique et l'estimation, ainsi que la modélisation mathématique, peuvent jouer un rôle important dans la résolution des problèmes d'exploitation des eaux géothermales. La carte structurale estimée de la couche la plus productive (la couche XIII) et une carte 3-D de la distribution de la température dans le gisement de Khankala ont été créées en utilisant le krigeage universel. Les résultats ont montré l'importance du facteur structuraltectonique et du mouvement des eaux souterraines dans la formation du régime de température du territoire. La modélisation de l'exploitation des gisements géothermiques de Khankala a permis de prévoirl’évolution de la température, de fournir des recommandations sur l'emplacement des puits d'injection et la distance entre les impacts à la couche productive, et d'explorer d'autres scénarios d'exploitation comme l'utilisation périodique de couches par doublets.Le développement de l'utilisation des eaux géothermales présente des avantages incontestables: respect de l'environnement et renouvelabilité. Afin de développer ce domaine en République Tchétchène, le soutien de l'Etat est nécessaire. L'absence d'un cadre législatif adapté et de systèmes spéciaux d'assurance pose des problèmes. L'utilisation des eaux géothermales des quatorze gisements explorés en République Tchétchène peut constituer une contribution significative à la production locale d'énergie et à la stabilité économique de la région, tout en apportant des avantages environnementaux par le remplacement partiel des combustibles traditionnels.Le travail présenté ici est une contribution au projet de station géothermique de Khankala qui a été lancé avec succès au début de 2016. La station géothermique de Khankala représente une nouvelle étape dans l'utilisation des eaux géothermales dans le Caucase du Nord car il s’agit du seul exemple russe de station géothermique avec une boucle fermée de puits de production et d'injection (“doublet”) et 100% de réinjection du fluide utilisé dans le réservoir. / Recently, considerable attention in the world is given to the use of renewable energy sources. Among them geothermal waters are of great importance due to ecological safety and economic efficiency of their use. Russia has confirmed high potential of geothermal water resources, but today only a small proportion is used. One of the most promising areas for geothermal waters is the Chechen Republic, which is at the 3rd place among the Russian regions for approved operational reserves of geothermal waters deposits, the largest of which is the Khankala deposit.Achievement of the sustainability in geothermal waters resource development requires an integrated approach and an important role in solving the problems of exploitation of thermal waters is played by geostatistical analysis and estimation, as well as mathematical modelling. The adjusted structural map of the most productive layer (layer XIII) and a 3-D map of temperature distribution within the Khankala deposit were created using universal kriging. Results approved the importance of the structural-tectonic factor and movement of groundwater in the formation of the temperature regime of the territory. Modelling of the Khankala geothermal waters deposit exploitation allowed to make prognosis of temperature changes, to provide recommendations on injection-production wells location and distance between down holes and to explore possible further exploitation scenarios such as periodic use of different layers by doublet systems.The development of geothermal waters use has undoubted advantages – environmental friendliness and renewability. In order to develop this domain in the Chechen Republic the state support is needed. Issues are the lack of a special legislative framework and special insurance systems. Use of geothermal waters of the 14 explored deposits in Chechen Republic can be a significant contribution to local energy production and economic stability of the region while bringing the environmental benefits of traditional fuels partial replacement.The present work was a contribution to the Khankala geothermal station project, which was successfully launched in the beginning of the 2016. The Khankala geothermal station represents a new stage in use of geothermal waters in the Northern Caucasus as it is the only Russian example of geothermal station with closed loop of production and injection wells (“doublet”) with 100% reinjection of used fluid back into reservoir.
210

Geothermal Potential of Sub-Volcanic Intrusions in a Typical Caldera Setting / Geotermisk potential av magma-intrusioner i en calderavulkan

Gestsson, Einar Bessi January 2018 (has links)
Sub-volcanic intrusions can form an extensive network of sills, dikes and other intrusion types that make up a plumbing system beneath volcanoes. Such intrusions are the heat source for high-temperature geothermal systems in volcanic areas and therefore, it is of great importance to study them in relation to geothermal exploration and production. In this thesis a part of the plumbing system of Breiðuvík caldera, an eroded central volcano in northeastern Iceland, is studied. A set of magmatic intrusions showing a great range in size and shapes, is exposed in Leirfjall, a mountain composed of the eroded caldera infill of the Breiðuvík volcanic system. Data from these intrusions and their host rock is used as the foundation for numerical modeling using finite element method (FEM) constructed in this thesis. The numerical modeling assumes heat transfer in porous media including conduction and convection where fluid flow is governed by the Darcy‘s law. The aims of it is to compare the cooling times of different intrusions and the temperature distribution caused by intrusions of different sizes and shapes. To obtain input parameters for the numerical modeling, a thermometry study based on the mineral chemistry of the magmatic intrusions in Leirfjall is conducted and the thermal and physical properties of the sedimentary host rock are estimated, while literature values are used for basaltic lava and hyaloclastite host rocks for comparison. The results of the numerical modeling suggest that higher maximum values of increased temperature are reached above one thick intrusions compared to multiple thinner intrusions. When comparing dikes and sills, the dikes raise the maximum temperature of the host rock more than the sills, while the sills raise the average temperature above the intrusions more than dikes. Results of the estimated heat transfer from an arrangement of intrusions similar to what is observed in Leirfjall suggests that a significant increase in maximum increased temperature caused by the intrusions would be short-lived, while the average increase would still be constant over a longer time. Despite of the simplified structure of the numerical models it is the hope that they will provide inspiring data for further research and contribute to a better understanding of the relationship between the shallow magmatic intrusions and geothermal systems. / Vulkaner är en viktig energikälla i många länder runt om i världen. Geotermisk vätska och ånga av högtemperatur som finns i vulkanområden kan utnyttjas för bland annat elproduktion och fjärrvärme. Värmekällan till de geotermiska områdena är magma som ligger ytligt i jordskorpan. All magma når inte ytan i utbrott, utan stannar under vulkanen i form av magmaintrusioner. Intrusionerna av olika former och storlekar utgör ett nätverk som tillsammans utgör vulkanens magma transportsystem. I denna studie studeras en uppsättning av magmaintrusioner på nordöstra Island. Intrusionerna har en gång befunnit sig längre ner i jordskorpan under ett aktivt vulkanområde men exponeras nu vid ytan på grund av glacial erosion. Intrusionernas storlek och form varierar, men de flesta återfinns som gångar, både vertikala och horisontella. När en magmatintrusion bildas värms omkringliggande berggrund och grundvatten upp. Studiens fokus är att undersöka hur temperaturfördelningen i omgivningen skiljer sig vid en stor intrusion jämfört med flera mindre intrusioner med totalt samma volym. Även effekten från olika typer av berggrund runt intrusionerna studerades genom att jämföra temperaturfördelningen och kylningstiderna för intrusioner i tre vanliga bergarter. Numerisk modellering användades för att besvara dessa frågor. Bergarternas fysiska och termiska egenskaper krävdes som ingångsparametrar för den numeriska modelleringen. Parametrana uppskattades genom laboratorieexperiment och termometriberäkningar från fältprover. Värden från publicerat material användes också i modelleringen. Resultaten från den numeriska modelleringen antyder att högre maximivärden för temperaturen nås i berget över en stor, enskild intrusion jämfört med flera mindre intrusioner. När man jämför vertikala og horisontella gångar, ökar de vertikala gångarna berggrundens temperatur mer än de horisontella, medan medeltemperaturen ökar mer över horisontella gångar än i vertikala gångar. Trots den numeriska modellens förenklade struktur är förhoppningen att den nya datan kan inspirera vidare forskning, och bidra till en bättre förståelse om förhållandet mellan grunda magmaintrusioner och geotermiska system.

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