Tesis sobre el tema "Thermal energy measurement"
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Faghani, Farshad. "Thermal conductivity Measurement of PEDOT:PSS by 3-omega Technique". Thesis, Linköpings universitet, Fysik och elektroteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-63317.
Texto completoVan, Nijnatten Peter A. "Measurement and modelling tools for the evaluation of directional optical and thermal radiation properties of glazing". Thesis, Oxford Brookes University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247601.
Texto completoPISTACCHIO, STEFANO. "Experimental measurement of the Molten Salts (MS) Thermal Conductivity and verification of the Thermocline stability in Thermal Energy Storage (TES) system". Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2015. http://hdl.handle.net/2108/202929.
Texto completoAhmad, Naveed. "Measurement of energy performance : Analysis of QUB method". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI051.
Texto completoQUB is a dynamic in-situ thermal characterization test method that has the potential to be conducted in a short duration of one to two nights. The robustness of QUB method with uncertainty in power level (during QUB heating phase), uncertainty in overall heat transfer coefficient at steady state, H_ref, and the outdoor temperatures a function of seasons needs to be established for real buildings.A dynamic state-space model is developed in this thesis to simulate QUB experiments. The state-space modelling involves generating a thermal circuit for each component of the building (walls, fenestration, ventilation system, etc.). The thermal circuits are then assembled to generate a single circuit for the entire building. The state-space model developed, is validated using thermal characteristics and measured data of a full-scale house (the twin house) provided by IEA EBC Annex 58. The numerical simulations of the QUB experiments on a house show that the method has only slight variation with uncertainty in power; for example, 30% error in optimum power can cause an error within 3 % of the reference value. A posteriori error analysis is performed by simulating QUB experiments in situations in which the real envelope has different characteristics than those assumed in the design of the experiment for QUB method. These results are then compared with a priori errors, a situation in which QUB experiments are performed with the knowledge of the real envelope. The error analysis shows that with 50 % error in the overall heat transfer coefficient (i.e. missing wall insulation situation), the QUB method results in an increased error of only 3¬¬ %. The precision of QUB method was tested also with the variation of solar radiation. QUB results on cloudy days show lesser variation as compared to sunny days. It was shown that the heat transfer from the delayed solar radiations entering through the walls of the building has an effect on the temperature evolution during the QUB experiment. This can lead to an increased error in QUB method. The QUB experiments are simulated during summer and winter to determine the impact of seasons on the accuracy of the method. The winter season shows more robust results as compared to summer months. The summer months show larger variation of results. It is verified that the large variation are due to small temperature difference between indoor and outdoor conditions during some of the summer nights. The experiments in summer season can be improved by increasing the set point temperature before the QUB experiment
ZAMPETTI, LORENZO. "Development of a low-cost system for thermal comfort measurement and control". Doctoral thesis, Università Politecnica delle Marche, 2017. http://hdl.handle.net/11566/245525.
Texto completoThis PhD dissertation summarizes the development and validation of innovative low cost systems for monitoring and controlling indoor environments. The systems explained in this document have their roots in the first version of Comfort Eye, an innovative thermal comfort measurement system, which is already documented in literature. This device can measure several environmental parameters in the room to obtain a real-time comfort assessment in multiple points of the space, according to ISO 7726 standard. Starting at this point, in the first part a new prototype of the monitoring system has been developed and tested highlighting improved features and measurement performances. Through single sensors calibration and uncertainty models from the GUM (Guide to the expression of Uncertainty in Measurement), the rated accuracy of the prototype in PMV measurement is ±0.1. The second part of the thesis is regarding an innovative subzonal HVAC control system, using the comfort data provided by Comfort Eye as controlled variable. That system has been designed and validated through some tests in an office-type environment, achieving an energy saving of 20%. The third and last part of this document finally shows another potential application of the Comfort Eye sensor: a people detection system for indoor ambient, with advanced counting and locating capabilities, has been tested inside office environment. The first attempt of validation shows an accuracy of 70% in detecting people.
Tink, Victoria J. "The measured energy efficiency and thermal environment of a UK house retrofitted with internal wall insulation". Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/33727.
Texto completoMurray, Elizabeth. "Measurement of prompt gamma-ray energy distribution and multiplicity of U-235 following thermal fission using STEFF". Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/measurement-of-prompt-gammaray-energy-distribution-and-multiplicity-of-u235-following-thermal-fission-using-steff(237a3928-95a1-4a5f-b905-44ad23368f98).html.
Texto completoVera-Sorroche, Javier. "Thermal homogeneity and energy efficiency in single screw extrusion of polymers : the use of in-process metrology to quantify the effects of process conditions, polymer rheology, screw geometry and extruder scale on melt temperature and specific energy consumption". Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/13965.
Texto completoAntón, Remírez Raúl. "Experimental and numerical study of the thermal and hydraulic effect of EMC screens in radio base stations : detailed and compact models". Doctoral thesis, KTH, Energiteknik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4265.
Texto completoQC 20100630
Park, Keunhan. "Thermal Characterization of Heated Microcantilevers and a Study on Near-Field Radiation". Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14597.
Texto completoGrozdek, Marino. "Load Shifting and Storage of Cooling Energy through Ice Bank or Ice Slurry Systems modelling and experimental analysis /". Doctoral thesis, Stockholm : Skolan för industriell teknik och management, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11119.
Texto completoKarami, Peyman. "Robust and Durable Vacuum Insulation Technology for Buildings". Doctoral thesis, KTH, Byggnadsteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176494.
Texto completoDagens byggnader ansvarar för omkring 40% av världens energianvändning och står också för en väsentlig del av utsläppen av växthusgaser. I Sverige kan ca 21 % av energianvändningen relateras till förluster genom klimatskalet. Miljonprogrammet är ett namn för omkring en miljon bostäder som byggdes mellan 1965 och 1974, och många av dessa byggnader har en dålig energiprestanda efter dagens mått. Huvudsyftet med denna studie har varit att utforska möjligheterna att använda vakuumisoleringspaneler (VIP:ar) i byggnader med viss fokus på tillämpning i Miljonprogrammets byggnader. Med en värmeledningsförmåga som är ca 8 - 10 gånger bättre än för traditionell isolering erbjuder VIP:arna unika möjligheter till förbättrad termisk prestanda med minimal isolerings tjocklek. Denna avhandling hade tre huvudsyften. Det första var att undersöka nya alternativ för kärnmaterial som bland annat kan reducera kostnaden vid produktion av VIP:ar. Tre nyutvecklade nanoporösa kiselpulver har testats med olika stationära och transienta metoder. En inom projektet utvecklad testbädd som kan anslutas till TPS instrument (Transient Plane Source sensor), har använts för att mäta värmeledningsförmågan hos kärnmaterial för VIP:ar, vid varierande gastryck och olika mekaniska laster. Slutsatsen blev att transienta metoder är mindre lämpliga för utföra mätningar av värmeledningsförmåga för nanoporösa kiselpulver låg densitet. Avvikelsen i resultaten är dock minimal för densiteter ovan en gräns då värmeledningen genom fasta material blir dominerande jämfört med värmeöverföring genom strålning. Det andra syftet har varit att föreslå ett nytt monteringssystem för VIP:ar som kan användas för att förbättra energieffektiviteten i byggnader som är typiska för Miljonprogrammet. Genom parametrisk analys och dynamiska simuleringar har vi kommit fram till ett förslag på ett nytt monteringssystem för VIP:ar som har utvärderats genom fullskaleförsök i klimatkammare. Resultaten från fullskaleförsöken visar att den nya tekniska lösningen förbättrar väggens U-värde med upp till 56 %. En förbättrad värmegenomgångskoefficienten för väggen i mitten av en VIP blev mellan 0.118 till 0,132 W m-2K-1 och värmeledningstalet centre-av-panel 7 mW m-1K-1 uppnåddes. Detta arbete innehåller dessutom en ny metod för att mäta köldbryggor i anslutningar med hjälp av infraröd termografi. En effektiv värmeledningsförmåga för 10.9 mW m-1K-1 uppnåddes. Resultaten tyder även på att den verkliga termiska prestandan av VIP:ar i konstruktioner är något sämre än mätvärden för paneler i laboratorium. En effektiv värmeledningsförmåga av 10.9 mW m-1K-1 ger dock väggkonstruktionen en utmärkt termisk prestanda. Det tredje syftet har varit att bedöma miljöpåverkan av en VIP-isolerad byggnad, från produktion till drift, eftersom en livscykelanalys av hela byggnader som är isolerade med vakuumisoleringspaneler inte har gjorts tidigare. Slutsatsen var att VIP:ar har en större miljöpåverkan än traditionell isolering, i alla kategorier förutom ozonnedbrytande potential. VIP:ar har en mätbar påverkan på de totala utsläppen av växthusgaser och primärenergianvändningen i byggnader när både produktion och drift beaktas. Miljöpåverkan av de använda VIP:arna är dock positiv jämfört med GWP av en standardbyggnad (en minskning med 6 %) medan primärenergianvändningen ökade med 20 %. Slutsatsen var att ytterligare användning av VIP:ar gynnas av reducerad energiförbrukning och alternativa energikällor i produktionen av nanoporösa kiselpulver medan användningen av alternativa kärnmaterial och återvinning av VIP kärnor kan hjälpa till att minska miljöpåverkan. En känslighetsanalys visade att valet av VIP:ar har en betydande inverkan på miljöpåverkan, vilket ger möjlighet att reducera den totala användningen av primärenergi i en byggnad med 12 % och utsläppen av växthusgaser kan vara minska, så mycket som 11 % när det gäller både produktion och drift under 50 år. Avslutningsvis är det möjligt att dra slutsatsen att VIP:ar är ett mycket konkurrenskraftigt alternativ för att isolera byggnader som är typiska för Miljonprogrammet. Dock krävs ytterligare undersökningar för att minimera de mätbara miljöeffekter som förvärvats i denna LCA-studie för VIP-isolerade byggnader.
QC 20151109
Simulations of heat and moisture conditions in a retrofit wall construction with Vacuum Insulation Panels
Textural and thermal conductivity properties of a low density mesoporous silica material
A study of the thermal conductivity of granular silica materials for VIPs at different levels of gaseous pressure and external loads
Evaluation of the thermal conductivity of a new nanoporous silica material for VIPs – trends of thermal conductivity versus density
A comparative study of the environmental impact of Swedish residential buildings with vacuum insulation panels
ETICS with VIPs for improving buildings from the Swedish million unit program “Miljonprogrammet”
Zima, Alexis. "Élaboration d’un outil de suivi et d’optimisation du fonctionnement énergétique d’un bâtiment tertiaire basé sur un modèle thermique analytique simplifié". Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC101/document.
Texto completoThe building field is responsible of about 40% of global energy consumption and a third of world greenhouse gas emissions. It is a main concern subject in climate change issues and fossil fuel independency. The aim of the PhD work is to bring more knowledge about thermal modeling and to create specific tools which are capable of globally optimize the office building energy management. The industrial purpose is associated with its area of expertise, which is advice in energy and ecologic transition. It concerns the difficulty to implement a retrofit action planning. Indeed, for small or middle retrofit actions, the initial study and metrology costs represent over 50% of the overall cost. This down payment induces a long return of investment. Faced with this prohibitive financial parameter, a lot of companies are reluctant to implement this type of actions. The proposed purpose is a solution that drastically reduces preliminary costs. The aspects addressed in this thesis are: the building operation state of art and its associated issues, the creation of reporting and collecting data tool of building operation and performance thanks to a dedicated in-situ measurement network, concomitant with the development of a simplified adjoin thermal model. It facilitates the understanding of its behavior. Then the final aspect are the two steps of optimization. The first is the observable building design and operation parameters with an inverse method, the second is the calculation of optimal energy consumptions. The approach is specifically oriented through the development of tools allowing a facilitated access to energy reduction action for national companies. This should assist the integration of an intelligence for energy optimization for building climatics and thermal equipments or usage. The result could be a new ergonomic man-machine interface for stock building effective management. In the facts, the problem is holistic and cannot be handle sectorally. It is imperative to integrate all the process involved in the building and its use (user behavior). The approach have been oriented to take later into account other parameters than strictly energy, as costs of comfort
Chen, Austin Miguel. "Couplage entre ventilation naturelle et stockage-déstockage d'énergie sensible en bâtiment : approche expérimentale et modélisation". Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0150/document.
Texto completoAs part of the search for solutions to reduce the energy consumption related to the refreshment of buildings, a test platform was set up in 2012 at the I2M and installed on the IUT site of the " University of Bordeaux. This platform is the result of a prototype of a PEHs building called Sumbiosi, carried out by a consortium gathered around the Bordeaux campus as part of its participation in the inter-university competition of the Solar Decathlon Europe 2012. It was conceived in such a way as to favor the passive storage of diurnal energy in winter and the semi-passive destocking of nighttime energy in summer. Two main elements allow a priori these functions of passive storage and retrieval of energy: a slab of high thermal mass located on the side of the glazed south facade of the building, and solar protections and openings controllable on the facades South, North and skylight of the building ; the latter provide the three fundamental principles of natural ventilation, which take place through the effects of thermal draft and wind force. The object of the work currently carried out has the initial objective of qualitatively understanding the storage and de-stocking of energy in the slab, the latter being subjected to radiative (external and internal) and convective exchanges (generated by natural convection, forced or mixed). They are intended to characterize precisely and quantitatively the coupling between this storage and release, and the circulations of air and radiative contributions observed. The implementation of a modeling, linking all these parameters is envisaged, with the aim of advancing towards a law controlling these mobile elements leading to optimum internal comfort conditions for building. The latter must enable us to show that an adequate choice of ventilation strategy allows a minimization of electrical consumption by avoiding the use of air conditioning as much as possible. To achieve this objective, the scientific approach adopted consisted in highlighting the role of the concrete slab in the storage / destocking of thermal energy, under the effect of different scenarios of natural ventilation of the platform. This slab was instrumented, discretely over its entire surface, in terms of heat flux sensors (Peltier and Captec), temperatures (T thermocouples), and air speed close to the slab. The first results, obtained during the summer period, clearly show the coupling between the phenomena of daily energy storage and destocking and the corresponding meteorological cycle for various scenarios controlling the moving elements of the building envelope (shutters, openings)
Dunne, Anthony Michael. "Measurements of thermal and radiation energy transport in laser and soft X-ray heated targets". Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336433.
Texto completoCazin-Bourguignon, Anne-Marie. "Contribution a l'etude du bilan thermique du recepteur de la centrale themis". Paris 6, 1986. http://www.theses.fr/1986PA066218.
Texto completoJose, Panangat James. "Simulation Validation with Real Measurements of an Intelligent Home Energy Management System". Thesis, Högskolan Dalarna, Energiteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:du-37214.
Texto completoAlshawaf, Hussain M. J. A. A. M. A. "A Novel Thermal Method for Pipe Flow Measurements Using a Non-invasive BTU Meter". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/101528.
Texto completoMS
Wennström, Christoffer. "Kontinuerlig temperaturmätning i bädden på gratevagnar". Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-66542.
Texto completoLuossavaara-Kiirunavaara Aktiebolag (LKAB) is a mining group with iron ore mining as the main business. One of the products is produced by refining iron ore to iron pellets, which is a quality and environmentally clever product in steel production. When iron pellets are produced by roasting green pellets the temperature is very important. The goal is to get as much oxidation as possible from hematite to magnetite and to get correct mechanical properties. To control the process it’s important to know the temperature of the green pellets specifically and not the surrounding mechanical structure, ceramics lining in the furnace and the influence from radiation. The goal of the project is to examine possibilities to measure temperature with a permanent measurement system of green pellets which are transported on grate cars trough pellet plant. The measurement system has to meet some requirements of environment, portability and operating time. Analysis of the environment has been made to get specification of what a measurement system has to withstand. Proposition about assembly location has been investigated by analysis of the environment. A thermal analysis has been made of electronic components, especially electronic components that can be used in a measurement system. A analysis has also been made of which electronic components that are suited for a measurement system and can withstand the heat. A development measurement system has been developed from the results of the analysis. The system has been constructed to measure the temperature of what a system can be exposed of on a grate car. This with wireless and data-logging support and future measurements possibilities with three thermocouples of type S. Wireless data transfer was examined to see what type is most suited for the task with knowledge of environment, transmission range, radiation and power consumption. Power sources was examined to find a power source with longest working time and highest functionality. Heat insulation and reflective materials has been investigated with the goal to get the temperature in the system enclosure as low as possible. Some different types of temperature sensors that can measure temperatures up to 1500°C and which can be mounted on a grate car has been evaluated.
Divi, Suresh Chandra. "Heat capacity measurements of pure and binary organic "plastic crystal" thermal energy storage materials and calculation of excess molar heat capacities". abstract and full text PDF (free order & download UNR users only), 2005. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1433411.
Texto completoKennedy, Jermaine L. "Investigations of fiber optic temperature sensors based on Yb:Y3Al5O12". [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001566.
Texto completoQUEIROZ, PATRÍCIA VALÉRIA SATHLER DE. "MEASUREMENT OF ELECTRIC ENERGY CONSUMPTION: ALGORITHM FOR DETECTING POTENTIAL USERS OF THERMO-ACCUMULATION AS AN ALTERNATIVE FOR LOAD SHIFT". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2011. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=34588@1.
Texto completoEsta dissertação desenvolveu-se de forma articulada com o projeto de PeD LIGH-ANEEL, coordenado pelo Programa de Pós-Graduação em Metrologia (PósMQI), Projeto Ref. PeD 003/2008, intitulado Racionalização do uso de energia e aplicação da termoacumulação como estratégia para proposição de tarifa diferenciada voltada a clientes comerciais de alto consumo. A dissertação teve como objetivo o desenvolvimento e validação de um algoritmo para identificação de clientes potenciais ao uso da tecnologia de termoacumulação. O trabalho orientou-se no contexto da crescente demanda por energia imposta ao setor elétrico pela expansão da economia, notadamente em horários de alta demanda. A motivação deste trabalho, atendendo aos interesses do PósMQI na área de energia, é oferecer uma ferramenta de auxílio à decisão para o planejamento energético das concessionárias. Como resultado obteve-se o mapeamento das curvas de cargas, obtidas por meio do sistema computacional desenvolvido (SIMCAR). Este sistema (amigável) permite enquadrar os clientes potenciais, segundo características de consumo estruturadas em três categorias indicativas do uso da termoacumulação: muito potencial, potencial e já modula. Dentre as conclusões, o algoritmo desenvolvido mostrou-se ferramenta eficaz de auxílio ao planejamento energético e a termoacumulação uma alternativa sustentável para adequação da matriz energética do país, podendo gerar economias de até 40 porcento.
An algorithm to measure and detect potential thermo-accumulation customers among the clients of a distributing utility was proposed in this work. Such algorithm uses statistical methods for the treatment of missing data and is applied to the measured hourly demands of medium and high voltage customers of the utility. Basically, the thermo-accumulation technique can be defined as a strategy to shift load from peak hours to off-peak hours. The algorithm allows the construction of load curves from the observed load series after the removal of outliers and/or missing values. From the profile of such curves, the algorithm produces the classification of the clients into three possible categories: higly potential, just potential and non potential (i.e. an already modulated client). Also important to mention this dissertation, is part of an R&D project developed for a brazilian southern utility. A friendly computer system named SIMCAR, developed in Visual Basic, implemented the proposed algorithm. As a final word, in surveys conducted with users of this technology, it was mentioned that the savings on energy consumption can be as high as 40 per cent.
Janbakhsh, Setareh. "A Ventilation Strategy Based on Confluent Jets : An Experimental and Numerical Study". Doctoral thesis, Linköpings universitet, Energisystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-117442.
Texto completoBakhtiari, Hossein. "Evaluation of Thermal Comfort and Night Ventilation in a Historic Office Building in Nordic Climate". Licentiate thesis, Högskolan i Gävle, Energisystem och byggnadsteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-33941.
Texto completoNocentini, Kévin. "Comportement thermo-hygrique de blankets aérogels de silice et applications à l’isolation des bâtiments". Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEM049/document.
Texto completoBuildings are the largest energy end-use sector and account for about 40 % of the total final energy consumption in the EU-28. A short-term strategy to efficiently reduce this consumption is to decrease thermal losses through the building envelope by improving its thermal insulation, while minimizing the reduction of the available indoor living space. In this context, the thesis deals with the study and development for pre-industrialization of super-insulating composite materials based on silica aerogel. The studied material is part of the aerogel blanket family and is obtained by an innovative ambient drying process. With a very low thermal conductivity and reinforced mechanical properties, aerogel blankets are of great interest for applications where they can offer a cost advantage due to a space-saving effect. Firstly, the thesis work aims at performing analyses of the thermo-physical properties of the studied aerogel blankets at the exit of the molding and drying processes, and during application, when they are subjected to different environmental stresses (mechanical, hygric …). Heat transfer modeling is developed to study the relationship between the morphological parameters of the material and thermal transfer within it. Secondly, the thesis work focuses on the study of the expected performances of an insulating system based on the aerogel blanket, by the study of the thermal behavior of an experimental building monitored under actual climate, as well as the use of whole building energy numerical simulations taking into account several constructive techniques, different wall configurations, for various European climates. The results obtained show that the aerogel blankets studied have a thermal conductivity as low as 0.016 W.m-1.K-1 and have promising applications for building thermal insulation needs
Moalla, Rahma. "Couches minces d'oxydes pyroélectriques épitaxiées sur Si pour la récupération d'énergie thermique". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEC050/document.
Texto completoDue to the wasted heat in ever more compact microelectronic devices, the harvesting of thermal energy has become interesting for self-powering small devices. Consequently, pyroelectric materials witch couple a change in temperature to a change in electrical polarization may be used for the conversion of the thermal energy to an electric energy without necessity of maintaining thermal gradients that is a main drawback in compact devices with thermoelectric materials. In this thesis, PbZro.52Tio.48O3 (PZT) and BaxSr1-xTiUO3 (x = l and x = 0.7), with high pyroelectric coefficients are chosen, elaborated in thin epitaxial layers, characterized structurally and electrically to study their potential for thermal energy harvesting. This work has two aspects: the first consists in the development and optimization of the growth conditions of epitaxial heterostructures integrated on Si. The second one focuses on the study of the functional properties ( ferroelectric, dielectric and pyroelectric) and the estimation of the energy harvesting efficiency mainly of PZT layers. A correlation between these two aspects is then done. A change in the crystal structure is shown on the Si-integrated stacks in comparison with equivalent structures grown on STO substrate. This structural behavior impacts directly the functional properties of the heteroepitaxial layers of PZT. Th us, an important anisotropy of these properties was demonstrated and completed by a study of the in plane properties using measurements by interdigital capacitors. These observations were consistent with measurements of X - ray diffraction as a function of temperature. Otherwise, different methods and configurations of pyroelectric coefficient measurements on PZT have allowed a better understanding of the phenomenon and the distinction of the various existing contributions. The indirect static measurement resulting from the variation of the remnant polarization as a function of the temperature gives the intrinsic (and secondary) pyroelectric contributions. However, the dynamic measurements of the pyroelectric current during a change of the temperature contain all the pyroelectric and non-pyroelectric contributions, such as the extrinsic effects and the relaxation current . Dynamic pyroelectric measurements under an electric field are near to the conditions of thermal energy harvesting cycles. Conduction currents appeared, even for good layers of thick dielectric PZT, and mask the pyroelectric currents. This makes the application of electric generator by thermodynamic cycles under electric field prohibitive. Passive components using low or no electrical field such as sensors should be considered
Chang, Chia-Hao y 張家豪. "Measurement and Analysis of Adsorption Chillers System combined with Solar Thermal Energy and Shallow Geothermal Energy". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9z8t8z.
Texto completo國立臺灣大學
機械工程學研究所
107
When the world began to promote energy conservation issues, the energy-saving benefits of air-conditioning systems are valued by many countries. The proportion of power consumption for energy dissipation is huge. Taiwan is hot in summer. The demand for air conditioning is great, which not only cost a lot, but also cause greatly environmental burden with carbon emissions. If it can directly use solar energy as a source of heat for air conditioners and use shallow geothermal energy to cooling, this way will greatly reduce power consumption and make air conditioners more energy efficient and environmentally friendly. This study use different parameters way to explore the performance of adsorption chillers combined with solar thermal energy and shallow geothermal energy . The COP of the adsorption chiller achieve 0.51 under the operating conditions, of 70 °C regenerative temperature, 22°C cooling water temperature, and 13~15 °C cold water temperature. Under the average radiation amount is about 860 W/m2, the thermal efficiency of the solar collector is about 0.6 and the overall system performance coefficient is about 0.31. It is estimated that use shallow geothermal energy instead of cooling tower system can save 44.6 m3 of water in summer. And it uses less 1.08 kW than cooling tower system.
Shih, Man-Wen y 施嫚雯. "Measurement of energy loss of magnetic microstructures under alternating magnetic field by thermal deflection method". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/00521111009361226295.
Texto completoBannerman, Andrew. "Economic evaluation of a district cooling system incorporating thermal storage". Thesis, 2003. http://hdl.handle.net/10413/4295.
Texto completoThesis (M.Sc.Eng.)-University of Natal, Durban, 2003.
Vera-Sorroche, Javier, Adrian L. Kelly, Elaine C. Brown, Philip D. Coates, N. Karnachi, E. Harkin-Jones, K. Li y J. Deng. "Thermal optimisation of polymer extrusion using in-process monitoring techniques". 2013. http://hdl.handle.net/10454/9742.
Texto completoPolymer extrusion is an energy intensive process, which is often run at less than optimal conditions. The extrusion process consists of gradual melting of solid polymer by thermal conduction and viscous shearing between a rotating screw and a barrel; as such it is highly dependent upon the frictional, thermal and rheological properties of the polymer. Extruder screw geometry and extrusion variables should ideally be tailored to suit the properties of individual polymers, but in practice this is rarely achieved due to the lack of understanding of the process. Here, in-process monitoring techniques have been used to characterise the thermal dynamics of the extrusion process. Novel thermocouple grid sensors have been used to measure melt temperature fields within flowing polymer melts at the entrance to an extruder die in conjunction with infra-red thermometers and real-time quantification of energy consumption. A commercial grade of polyethylene has been examined using three extruder screw geometries at different extrusion operating conditions to understand the process efficiency. Extruder screw geometry, screw rotation speed and set temperature were found to have a significant effect on the thermal homogeneity of the melt and process energy consumed. (C) 2012 Elsevier Ltd. All rights reserved.
Toews, William Henry. "An investigation of low energy quasiparticle excitations via thermal conductivity measurements". Thesis, 2012. http://hdl.handle.net/10012/7122.
Texto completo"Thermal Resistance Measurements of Triply Periodic Minimal Surface Structures (TPMS) of the Thermogalvanic Brick". Master's thesis, 2020. http://hdl.handle.net/2286/R.I.57209.
Texto completoDissertation/Thesis
Masters Thesis Mechanical Engineering 2020