Dissertations / Theses on the topic 'Thermal analysis'
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Collins, Brian Harris. "Thermal imagery spectral analysis." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA320553.
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Thesis (M.S. in Systems Technology (Space Systems Operations)) Naval Postgraduate School, September 1996.Thesis advisor(s): R.C. Olsen, David Cleary. "September 1996." Includes bibliographical references (p. 159-161). Also available online.
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Smith, Travis R. "Thermal analysis of PANSAT." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA341788.
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Thesis (M.S. in Astronautical Engineering) Naval Postgraduate School, December 1997."December 1997." Thesis advisor(s): Oscar Biblarz, Ashok Gopinath. Includes bibliographical references (p. 89-90). Also available online.
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Samba, Ahmadou. "Battery electrical vehicles analysis of thermal modelling and thermal management." Caen, 2015. http://www.theses.fr/2015CAEN2003.
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L’avancée de la recherche sur les batteries a conduit à une utilisation massive des batteries Lithium-ion de grande capacité dans les véhicules électriques. De tels designs, en grand format, ont l'avantage de réduire le nombre de cellules interconnectées dans les packs de batteries. Dans les applications de transport, le temps de recharge des batteries constitue un frein au développement des véhicules électriques. L'augmentation du courant de charge peut soumettre à la batterie à des situations très critiques et peut ainsi entrainer une augmentation considérable de sa température. En long terme, ces phénomènes peuvent conduire à la réduction de sa durée de vie ainsi que ses performances et dans certains cas à l’emballement thermique. Afin d’éviter de telles situations, il est nécessaire d’optimiser la gestion thermique de manière à maintenir la batterie dans une gamme de températures de fonctionnement sûre. Ceci passe par la mise en place d’un modèle thermique capable de prédire la température d’une cellule et d’un pack de batterie à différentes conditions de fonctionnement et ensuite proposer différentes stratégies de refroidissements. Compte tenu de la forme et des dimensions du type de batterie utilisé (batterie « pouch ») un modèle électro-thermique est développé afin de prédire la distribution de température de la cellule, ce modèle nécessite moins de paramètres d'entrée et possède une grande précision. En outre, un nouvel outil d'estimation des paramètres thermiques a été développé. Le comportement thermique de la batterie, soumise à des conditions de fonctionnements extrêmes, a été étudié avec ce modèle. De ces résultats, on remarque que la cellule de batterie présente une distribution thermique non-uniforme lorsque celle-ci est parcourue par des courants de grandes amplitudes. Ce constat nous amène à étudier le design des batteries de type « pouch » afin d’élire celle qui présente une distribution thermique et électrique plus uniformes. Pour se faire un modèle 3D électrochimique-thermique a été développé. Enfin, différentes stratégies de gestion thermique des batteries telles que: le refroidissement actif par liquide et passif utilisant un matériau à changement de phase (liquide-solide à changement de phase) incorporé dans une mousse d'aluminium, ont été étudiées puis comparés en appliquant un cycle de conduite, provenant d’un véhicule tout électrique de la gamme Peugeot. L'objectif principal est de réduire la complexité, le poids, le volume, le coût et également de maintenir à un haut niveau de sureté de fonctionnement du module de batterieAdvanced research on rechargeable Lithium-ion batteries has allowed for large format and high-energy batteries to be largely used in Battery Electric Vehicles (BEVs). For transportation applications, beside limitations of driving range, long charging time is still considered as an important barrier for a wide use of BEVs. The increase of the charging current amplitude may however subject the battery to stressful situations and can significantly increase the temperature of the battery. These phenomena reduce the battery’s lifetime and performances and in worst-case scenario, thermal runaway can occur. To avoid this, there is a need for an optimized thermal management in order to keep the battery in a safe and beneficial range of operating conditions. Firstly, in this PhD dissertation a two-dimensional electrical-thermal model has been developed to predict the cell temperature distribution over the surface of the battery. This model requires less input parameters and still has high accuracy. In addition, a novel estimation tool has been developed for estimation of the thermal model parameters. Furthermore, the thermal behavior of the proposed battery has been investigated at different environmental conditions as well as during the abuse conditions for assessment of thermal stability of the battery. Taking into account the harsh thermal distribution, an advanced three-dimensional electrochemical-thermal model has been developed in order to investigate the impact of the cell design on the thermal, voltage and current distributions in order to avoid high non-homogenous distribution. The developed model allows us to optimize the cell design, in order to achieve the longest lifetime and high performances of battery cell. Finally, different thermal management strategies such as liquid cooling and passive cooling using phase change material embedded in an aluminium-foam (liquid-solid phase change) have been investigated and compared in depth by applying real BEV drive cycles. The main objective of this study is to decrease the complexity, the weight, the volume and the cost and to maintain high safety according to the best strategy
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Deshpande, Chinmay Vishwas. "Thermal analysis of vascular reactivity." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1342.
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Brauer, G., M. Jungmann, E. Altstadt, M. Werner, R. Krause-Rehberg, A. Rogov, and K. Noack. "Thermal Analysis of EPOS components." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-27950.
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We present a simulation study of the thermal behaviour of essential parts of the electron-positron converter of the positron source EPOS at the Research Center Dresden-Rossendorf. The positron moderator foil and the upper tube element of the electrostatic extraction einzellens are directly exposed to the primary electron beam (40 MeV, 40 kW). Thus, it was necessary to prove by sophisticated simulations that the construction can stand the evolving temperatures. It was found that thin moderator foils (< 20...40 µm) will not show a too strong heating. Moreover, the temperature can be varied in a wide range by choosing an appropriate thickness. Thus, the radiation-induced lattice defects can at least partly be annealed during operation. The wall of the extraction lens which is made from a stainless steel tube must be distinctly thinned to avoid damage temperatures. The simulations were performed time dependent. We found that the critical parts reach their final temperature after less than a minute.
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Guven, Oytun. "Thermal Analysis Of Power Cables." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12609040/index.pdf.
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This thesis investigates temperature distribution and hence heat dissipation of buried power cables. Heat dissipation analysis of a simple practical application and the parameters that affect the heat dissipation are discussed.
In analyzing temperature distribution in the surrounding medium , a computer program is developed which is based on gauss-seidel iteration technique. This method is applied to a sample test system and heat dissipation curves for several parameters are obtained. Also, current carrying capacities of various types of cables are determined using dissipated heat values.
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Bernving, Niels. "Numerical thermal analysis of SEAM." Thesis, KTH, Rymd- och plasmafysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-218037.
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This thesis is on the topic of numerical thermal analysis, specically of the SmallExplorer for Advanced Missions SEAM. SEAM is a 3 unit Cubesat, which isgoing to be launched in a sun-synchronous orbit to measure the magnetic sphere.It makes use of a boom deployment system to remove the sensors from themagnetic eld inuences of the body. The goal of this thesis is to study thethermal behaviour of the satellite, specically the internal components and thethermal deformation of the boom structure. The numerical simulations makeuse of the Monte Carlo Ray-tracing method. Furthermore thermal vacuumcycle tests have been compared to the thermal model as a form of validation.Additionally the thesis also serves as a nal thermal analysis of the satellite, tocheck if all components operate within their specied thermal operating range.Detta examensarbete handlar om numerisk termisk analys av SEAM (SmallExplorer for Advanced Missions) satellit. SEAM är en 3U CubeSat, som skaskickas upp i solsynkron bana kring jorden för att utföra magnetfältmätningar.Satelliten använder sig av en utfällbar bom för att separera magnetsensorer frånmagnetiska störningar från satellitens elektronik. Examensarbetet syftar tillatt studera termiska beteende av satelliten, specifikt temperaturområden i bananför interna komponenter samt termisk deformation av den utfällbara bomstrukturen.Numeriska simuleringar av strålningsöverföring av värme använderMonte-Carlo metod för att följa strålar. Experimentella resultat från termiskvakuum testning av satelliten har jämförts med termiska modellen för att valideraden. Examensarbetet utgör den slutliga termiska analysen av satelliten, föratt säkerställa att alla komponenter används inom deras specificerade temperaturområde.
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Jarrell, Robert Perry. "Natural daylighting : a thermal analysis." Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/22350.
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Musmar, Sa'ed Awni. "In-situ thermal analysis probe." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102686.
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A new thermal analysis technique was developed and tested. It makes use of the improvements in heat transfer characteristics associated with recent advances in heat pipe technology. Heat is extracted from a liquid sample of a melt taken in-situ from within a vessel or furnace. The rate of heat extraction is such as to cause the sample to solidify. The technique was tested both in the laboratory and on an industrial scale (Grenville Castings, Perth, Ontario). Aluminum alloys including 356, 319, Al-xSi, Al-Si-Cu-xMg, and 6063 were subjected to various melt treatments and were used to carry out the tests. Classical thermal analysis was also carried out simultaneously under the same melt conditions using a preheated graphite cup.The comparison showed that the new technique has great potential over classical thermal analysis. The major advantages of the new method are that it conducts the analysis inside the melt (since it is no longer necessary for a physical sample to be removed from the melt itself), it consumes less time and the cooling rate can be precisely controlled during the solidification process. Moreover, it produces curves of greater detail and of better resolution than conventional techniques. In fact, the detail is of such resolution that, in some cases, the cooling curves may be used to infer the chemical composition of certain components of the melt, a fact which equates to a form of rapid chemical analysis. The peaks in the signal which refer to intermetallic formation are of better resolution and more identifiable when the new technique is used. The size of the peaks obtained using the new probe is about three times greater than that obtained by the classical method. With this new technique it becomes possible to correlate the area below the intermetallic peak to the concentration of iron or copper in the melt. This is a feature which makes the new thermal analysis probe act as a rapid chemical analyzer for selected constituents.
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Goodman, J. S. "Thermal analysis of ramjet engines." Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445768.
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Cash, A. A. J. "Thermal analysis of petroleum materials." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233909.
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McEuen, Scott Jacob. "Thermal analysis of biochemical systems." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81702.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 109-112).
Scientists, both academic and industrial, develop two main types of drugs: 1) small molecule drugs, which are usually chemically synthesized and are taken orally and 2) large molecule, biotherapeutic, or protein-based drugs, which are often synthesized via ribosome transcription in bacteria cells and are injected. Historically, the majority of drug development, revenue, and products has come from small molecule drugs. However, recently biotherapeutic drugs have become more common due to their increased potency and specificity (the ability to chemically bond to the targeted protein of interest). Researchers now estimate that as much as 50% of current drug development activities (pre-market approval) are focused on these protein-based drugs. There are several well-documented steps necessary in the development of a new large molecule drug. One critical element during the end of the biotherapeutic drug discovery phase and the beginning of the manufacturing phase is known as preformulation or formulation development. During this stage scientists systematically test the effects of adding various excipients (non-protein additives added to enhance the protein stability, solubility, activity of the drug, etc.) to the potential large molecule drug. Differential scanning calorimetry (DSC) is a common technique used to perform these formulation studies. In a classic DSC experiment, a protein is heated from 20-80°C and the heat absorbed while the protein unfolds is measured. Many researchers prefer the use of a DSC instrument because of its label-free nature, meaning that no fluorescent or radio-labeled tag is necessary to perform the measurement. The heat absorbed during the unfolding event(s) is directly measured. However, current commercial DSC instruments suffer from high protein consumption (especially when compared to other labeled techniques), low sensitivity, and slow throughput. The aim of this thesis is to address two of the three areas mentioned above: high protein consumption and slow throughput. Since many formulation development studies are performed at therapeutic or high protein concentrations, one can reduce the experimental cell volume and thereby reduce the amount of protein material consumed. However, since there is less sample, less heat is produced. While in the literature there are several heat transfer models that describe how a DSC instrument literature there are several heat transfer models that describe how a DSC instrument functions, there are surprisingly few heat transfer models that detail how ambient temperature disturbances impact the thermal measurement. To better describe this behavior, a simplified state-space thermal model was created to predict the disturbance rejection of a custom DSC instrument. This model was verified experimentally using linear stochastic system identification techniques. To reduce sample throughput, the prototype calorimeter cell was made from disposable materials. Because the majority of protein systems are thermodynamically irreversible, at elevated temperatures the protein solution often aggregates and needs to be cleaned before a subsequent experiment can be run. This cleaning process constitutes a significant portion of the overall time to run an experiment. This thesis documents a fully functional DSC instrument that, while not completely disposable, has been designed, built, and tested with disposable microfluidic materials. Future work would then solve the technical hurdles of repeatably loading disposable microfluidic cells into the DSC instrument.
by Scott Jacob McEuen.
Ph.D.
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Brauer, G., M. Jungmann, E. Altstadt, M. Werner, R. Krause-Rehberg, A. Rogov, and K. Noack. "Thermal Analysis of EPOS components." Forschungszentrum Dresden-Rossendorf, 2008. https://hzdr.qucosa.de/id/qucosa%3A21622.
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We present a simulation study of the thermal behaviour of essential parts of the electron-positron converter of the positron source EPOS at the Research Center Dresden-Rossendorf. The positron moderator foil and the upper tube element of the electrostatic extraction einzellens are directly exposed to the primary electron beam (40 MeV, 40 kW). Thus, it was necessary to prove by sophisticated simulations that the construction can stand the evolving temperatures. It was found that thin moderator foils (< 20...40 µm) will not show a too strong heating. Moreover, the temperature can be varied in a wide range by choosing an appropriate thickness. Thus, the radiation-induced lattice defects can at least partly be annealed during operation. The wall of the extraction lens which is made from a stainless steel tube must be distinctly thinned to avoid damage temperatures. The simulations were performed time dependent. We found that the critical parts reach their final temperature after less than a minute.
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Armstrong, Christopher. "Inoculant measurement with thermal analysis." Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279066.
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Over time the level of inoculant will decrease due to fading and this needs to be compensated bymore additions of inoculant. When casting CGI400 at Scania a one-step method is used, and the inoculant additions are based on the last ladle from the previous oven. Longer stops in production will result in the previous oven not being representable and more inoculant should be added. A method to establish the inoculation level of the base iron in the oven would make it easier to control the process. This study was about inoculation measurements with the help of thermo- analysis of the melt in the oven to get a better understanding how it fluctuates between ovens and changes over time. The study is also about how to implement this tool into production in a foundry. With the help of thermo- analytic measurements, the inoculation level of the melt was established, and the method was also used to see how the level of inoculant changed over. To establish the inoculation additions needed, the saturation point of inoculant was investigated. The results from the study shows that the starting level of inoculant is too low in the melt it also shows that the inoculation level fluctuates over time. The conclusions that can be drawn from this study is that thermos analysis can be used in production to establish the inoculation level, but moremeasurements needs to be conducted to determine its accuracy.Över tid så minskar ympnivån i en smälta på grund av fading och detta måste kompenseras med mertillsatser av ymp. Vid gjutning av CGI400 på Scania används en en-stegs metod där man baserar ymptillsatsen i skänken på vad ympnivån var i sista skänken från den tidigare ugnen. Vid längre produktionsstopp kommer inte ympnivån från ugnen innan vara representativ utan mer ymp måste tillsättas. En metod för att bestämma ympnivån av basjärnet i ugnen skulle göra det lättare att styra processen. Denna studie handlar om ympmätning med hjälp av termisk analys i bas smälta för att få en bättre förståelse för hur den fluktuerar mellan ugnar och ändras över tid. Studien handlar också om hur man ska kunna applicera denna mätmetod i produktionen på ett gjuteri. Med hjälp av termo analytiska mätningar skulle grundnivån av ymp i smältan bestämmas och även för att se hur nivån ändrades över tiden. För att bestämma tillsatsen av ymp som borde tillföras undersöktes mättnadspunkten av ymp och hur den kunde tillsättas i skänk. Resultaten från studien visar att grundnivån av ymp är för låg och resultaten visar också att nivån av ymp fluktuerar både upp och ner ökar tid vilket inte var vad man hade förväntat sig och även det finns flera faktorer som kan påverka nivån. Slutsatsen som kan dras är att termisk analys kan användas i produktion för att bestämma ympnivån, men mer mätningar behövs för att bestämmadess noggrannhet.
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Ocak, Mustafa. "Conduction Based Compact Thermal Modeling For Thermal Analysis Of Electronic Components." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612100/index.pdf.
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Conduction based compact thermal modeling of DC/DC converters, which are
electronic components commonly used in military applications, are investigated.
Three carefully designed numerical case studies are carried out at component, board
and system levels using ICEPAK software. Experiments are conducted to gather
temperature data that can be used to study compact thermal models (CTMs) with
different levels of simplification.
In the first (component level) problem a series of conduction based CTMs are
generated and used to study the thermal behavior of a Thin-Shrink Small Outline
Package (TSSOP) type DC/DC converter under free convection conditions. In the
second (board level) case study, CTM alternatives are produced and investigated for
module type DC/DC converter components using a printed circuit board (PCB) of an
electro-optic system. In the last case study, performance of the CTM alternatives
generated for the first case are assessed at the system level using them on a PCB
placed inside a realistic avionic box.
v
Detailed comparison of accuracy of simulations obtained using CTMs with various
levels of simplification is made based on experimentally obtained temperature data.
Effects of grid size and quality, choice of turbulence modeling and space
discretization schemes on numerical solutions are discussed in detail.
It is seen that simulations provide results that are in agreement with measurements
when appropriate CTMs are used. It is also showed that remarkable reductions in
modeling and simulation times can be achieved by the use of CTMs, especially in
system level analysis.
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Bhatia, Padampat Chander. "Thermal Analysis of Lithium-Ion Battery Packs and Thermal Management Solutions." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1371144911.
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Ozbay, Sercan. "Thermal Analysis Of Stirling Cycle Regenerators." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613541/index.pdf.
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Stirling cycle cryocoolers are used widely in military applications. The regenerator is the key element of Stirling cycle cryocoolers. It is known that performance of the regenerator directly affects the cryocooler performance. Therefore, any improvement on the regenerator will lead to a more efficient cryocooler. Thus, it is essential to have an idea about regenerator parameters and their effects on the system.
In this study Stirling engine regenerator, which is constructed by wire mesh screens, is accepted as a porous medium. Using energy balance and continuity equation, matrix and fluid thermal equations are derived. Simplified versions of these equations are obtained for not only the ideal case, but also two other cases which take into account the effects of longitudinal conduction and the effects of regenerator wall. A computer code is developed in Matlab to solve these equations using finite difference method. The developed code is validated by using Sage. Afterwards, effects of all regenerator parameters on regenerator performance are investigated in detail and results are presented. To make this investigation easier, a graphical user interface is also built (in Matlab) and used.
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Björnberg, Anton, and Erik Larsson. "Thermal Analysis and Control of MIST." Thesis, KTH, Skolan för teknikvetenskap (SCI), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214739.
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A thermal analysis has been conducted on thesatellite MIST to learn how well different temperature requirementsare met in its latest configuration. In the process botha geometrical and a mathematical thermal model have beenrefined and updated and new information regarding internal heatdissipation has been added. The three thermally most extremecases have been simulated using the software Systema-Thermicaand the results show that several units aboard are not within theirtemperature limits. Different possibilities to resolve the issues,including the use of passive thermal control, have been discussed.
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Nass, Kirk A. "Dielectric thermal analysis of polymeric matrices /." Thesis, Connect to this title online; UW restricted, 1989. http://hdl.handle.net/1773/9897.
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Hassan, Muhammad Zahir. "Thermal Deformation Analysis Disc Brake Squeal." Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505054.
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Han, Yunqing. "THEORETICAL STUDY OF THERMAL ANALYSIS KINETICS." UKnowledge, 2014. http://uknowledge.uky.edu/me_etds/35.
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In the past decades, a great variety of model fitting and model free (isoconversional) methods have been developed for extracting kinetic parameters for solid state reactions from thermally stimulated experimental data (TGA, DSC, DTA etc.). However, these methods have met with significant controversies about their methodologies. Firstly, model-fitting methods have been strongly criticized because almost any reaction mechanism can be used to fit the experimental data satisfactorily with drastic variations of the kinetic parameters, and no good criterion exists to tell which mechanism is the best choice. Secondly, previous model free methods originated from the isoconversional principle, which is often called the basic assumption; previous studies comparing the accuracy of model free methods have not paid attention to the influence of the principle on model free methods and, therefore, their conclusions are problematic.
This work gives, firstly, a critical study of previous methods for evaluating kinetic parameters of solid state reactions and a critical analysis of the isoconversional principle of model free methods. Then an analysis is given of the invariant kinetic parameters method and recommends an incremental version of it. Based on the incremental method and model free method, a comprehensive method is proposed that predicts the degree of the dependences of activation energy on heating programs, and obtains reliable kinetic parameters. In addition, this work also compares the accuracy of previous methods and gives recommendations to apply them to kinetic studies.
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Grandy, David Brian. "The micro-thermal analysis of polymers." Thesis, Loughborough University, 2002. https://dspace.lboro.ac.uk/2134/35677.
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This study is concerned with the development of micro-thermal analysis as a technique for characterising heterogeneous polymers. It is divided into two main parts. In the first part, the use of miniature Wollaston wire near-field thermal probes mounted in an atomic force microscope (AFM) to carry out highly localised thermal analysis (L-TA) of amorphous and semi-crystalline polymers is investigated. Here, the temperature of the probe sensor or tip is scanned over a pre-selected temperature range while in contact with the surface of a sample. It is thereby used to heat a volume of material of the order of several cubic micrometres. The effect of the glass transition, cold crystallisation, melting and degree of crystallinity on L-TA measurements is investigated. The materials used are poly(ethylene terephthalate), polystyrene and fluorocarbon-coated poly(butylene terephthalate). The primary measurements are the micro- or localised analogues of thermomechanical analysis (L-TMA) and differential thermal analysis (L-DTA). The effect of applying a sinusoidal modulation to the temperature of the probe is also investigated.
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Williams, Adrian Michael. "Thermal Vacuum Chamber Refurbishment and Analysis." DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1860.
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Spacecraft are subject to different environments while on orbit around the Earth and beyond. One of the most critical of these environments that must be counteracted is the thermal environment. Each spacecraft has an operating temperature that is specified in the mission requirements. The requirement stems from internal component operating temperatures that are critical to mission success. Prior to placing the spacecraft in orbit, engineers must be sure that the spacecraft will survive or risk losing the mission entirely.
The primary way to mitigate this risk is to use a thermal vacuum chamber (TVAC). The chamber is designed to resemble a space environment by reducing the pressure within the chamber to 1e-6 Torr. The differentiating factor between a vacuum chamber and a thermal vacuum chamber is the ability for the TVAC to complete a process known as thermal cycling using a temperature controller. Thermal cycling begins at a set temperature and increases within the chamber to a designated hot temperature expected to be seen on orbit. After the maximum temperature is reached, it remains there for a specified amount of time in what is called a soak. The controller then reduces the temperature to a specified cold temperature where a second soak takes place. Finally, the temperature is returned to the initial temperature and the process is repeated for a number of cycles until testing is complete.
For the purpose of this thesis, only the initial temperature increase and the first soak are being investigated. The chamber being used to run these experiments was graciously donated by MDA US Systems, however, no additional documentation was provided with the chamber. The Two identical black coated aluminum and brass cylinders have been chosen to be run with three different temperature profiles. The profiles are manually designed in the temperature controller on the chamber and vary by final soak temperature. To supplement the testing, simulations have been created for each test case in order to verify the computer model of the chamber. The simulations utilize AutoCad and Thermal Desktop to provide the results for comparison.
Each of the tests were completed successfully and produced good results that corresponded well to the simulation. The largest difference between the simulation cylinder temperature and the experimental cylinder temperature was 1.9 $^{\circ}$C. The effectiveness and efficiency of the blue chamber was compared to the other thermal vacuum chamber in the Space Environments lab. Overall, the Blue Chamber proved to be more robust and much easier to operate than the HVEC thermal vacuum chamber.
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Larsson, Erik, and Anton Björnberg. "Thermal Analysis and Control of MIST." Thesis, KTH, Skolan för teknikvetenskap (SCI), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210861.
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A thermal analysis has been conducted on thesatellite MIST to learn how well different temperature requirementsare met in its latest configuration. In the process botha geometrical and a mathematical thermal model have beenrefined and updated and new information regarding internal heatdissipation has been added. The three thermally most extremecases have been simulated using the software Systema-Thermicaand the results show that several units aboard are not within theirtemperature limits. Different possibilities to resolve the issues,including the use of passive thermal control, have been discussed.
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Saw, Wee Hee. "Human thermal experimentation, analysis & control /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p1420926.
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Thesis (M.S.)--University of Missouri-Columbia, 2003.Accompany CD-ROM contains complete dissertation in Microsoft Word documents. Typescript. Vita. Includes bibliographical references. Also available on the Internet.
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McLaughlin, Jim. "ORTHOPEDIC DRILLING & THERMAL INJURY ANALYSIS." Master's thesis, Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/512272.
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Mechanical EngineeringM.S.M.E.
In orthopedic surgery, fixation pins are used to provide stability of bone segments to ensure proper healing. The drilling process to implant these pins can generate a considerable amount of heat. Raising the temperature of bone tissue above 47°C for a prolonged amount of time can cause cell death in a process called thermal osteonecrosis. Should bone tissue surrounding implants like fixation pins die and begin to break-down, the stability of said implants becomes at risk for failure. The failure of a surgical implant can be costly, resulting in additional surgery for repairs and prolonged recovery time. Reducing the amount of heat generated during drilling can greatly lessen the potential for thermal injury. This study aims to evaluate the effect of varying drilling parameters on heat generation, namely examining if internal temperatures be reduced by varying the rotational velocity and feed rate in orthopedic drilling, and thus reduce the probability of thermal osteonecrosis. Experiments were performed comparing combinations of feed rates and spindle speeds for the drilling process parameters, specifically feed rates of 1.5, 3.0, 5.0, 9.0, and 12.0 mm⁄s and spindle speeds of 1000, 2000, and 3000 rpm. The tests used traditional smooth-shaft fixation pins, with trocar tips, that were drilled into 20 PCF synthetic bone. A Flir T440 infrared camera was used to record thermal video of the drilling process. Data acquired from the infrared camera shows that lower spindle speeds resulted in lower maximum temperatures while varying feed rates had only a moderate effect. With these results orthopedic drilling can be optimized for reduced heat generation and the prevention of thermal osteonecrosis.
Temple University--Theses
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Tiedemann, Maik. "Thermal analysis and thermal control system requirements for a solar sail Mars mission." Master's thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-02162010-020124/.
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Hodges, Christopher Sean. "Theory and practice of near-field thermal probes for microscopy and thermal analysis." Thesis, Lancaster University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322519.
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Haskaraman, Feyza. "Thermal and hydraulic analysis of the adsorption bed of the adsorptive thermal battery." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/105706.
Full textAbstract:
Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (page 23).
Electric vehicles (EVs) have a drawback of relatively short drive range that affects their adoption rate. In order to increase the drive range of EVs, replacing heating, ventilation and air conditioning (HVAC) system with a novel absorbent system of materials and methods is widely investigated. This work focuses on the analysis of the design of such a system to suggest efficiency improvements. The thermal insulation and choice of pump required for the optimal function of the adsorptive bed that carries the novel material are analyzed respectively to understand system performance. A thermal resistance analysis was performed in order to understand the undesirable heat loss from the system that decreases the efficiency. Moreover, pressure loss in the piping system was determined theoretically to choose a compatible pump. This analysis also resulted in a modular code that can be used to test different design parameters for future work,
by Feyza Haskaraman.
S.B.
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Demetriou, Louis. "Advanced spreadsheet based methodology for the dynamic thermal modelling of buildings." Thesis, Brunel University, 2006. http://bura.brunel.ac.uk/handle/2438/7895.
Full textAbstract:
Thermal analysis of buildings was carried out using simplified design tools, prior to the widespread use of computers. Since the early 1980's, the rapid growth of computational power has lead to the introduction of many building dynamic thermal simulation software programs. The accurate performance of many of these programs has lead to the view that manual calculation methods should only be used as indicative design tools. The CIBSE admittance method is based on the fundamentals of building heat transfer, its calculations procedures being simplified for use on hand held calculators. Manual calculation methods must be developed for use on more powerful calculators, if greater accuracy is required. Such calculators are available in the form of computer spreadsheet programs. The computational power of the computer spreadsheet program, combined with suitable mathematical thermal modelling techniques, has thus far, remained unexploited. This thesis describes the development of a powerful manual thermal design method, for application on a computer spreadsheet program. All the modes of building heat transfer are accurately modelled. Free-running or plant-controlled spaces can be simulated. In the case of a single zone, the accuracy of the new manual dynamic thermal model is comparable with commercially available software programs. The level of mathematical modelling complexity is limited only by computer power and user ability. The Iterative Frequency Domain Method (IFDM) and the Adiabatic Iterative Frequency Domain Method (AIFDM) are alternative mathematical simulation techniques developed to form the core of the Thermal Analysis Design Method. In the IFDM and AIFDM, the frequency domain and numerical iteration techniques have been integrated to produce a thermal simulation method that can model all non-linear heat transfer processes. A more accurate formulation of sol-air temperature, a window sol-air temperature and an accurate reduced internal long-wave radiant exchange model is a sample of further innovations in the thesis. Many of the developments described in the thesis, although designed for the computer spreadsheet environment, may also be employed to enhance the performance of some of the current dynamic thermal models of buildings.
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Victor, Eric L. "Thermal analysis of PANSAT electric power subsystem." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA283417.
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Behrens, Richard J. "Change detection analysis with spectral thermal imagery." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1998. http://handle.dtic.mil/100.2/ADA356044.
Full textAbstract:
Thesis (M.S. in Space Systems Operations) Naval Postgraduate School, September 1998."September 1998." Thesis advisor(s): Richard Christopher Olsen, David D. Cleary. Includes bibliographical references (p. 129-131). Also available online.
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Ha, Min Seok. "Thermal analysis of high power led arrays." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31803.
Full textAbstract:
Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2010.Committee Chair: Samuel Graham; Committee Member: J. Rhett Mayor; Committee Member: Yogendra Joshi. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Arunachalam, Bharath K. "Thermal analysis of hypothermic tissue preservation methods." Cincinnati, Ohio : University of Cincinnati, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1163482713.
Full textAbstract:
Thesis (M.S.)--University of Cincinnati, 2005.Title from electronic thesis title page (viewed Jan. 30, 2007). Includes abstract. Keywords: heat transfer, tissue preservation Includes bibliographical references.
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Mahfoud, Musbah Saleh. "Controlled thermal analysis using heat pipe technology." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ37004.pdf.
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Bihari, Kathleen L. "Analysis of Thermal Conductivity in Composite Adhesives." NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20010808-130536.
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BIHARI, KATHLEEN LOUISE. Analysis of Thermal Conductivity in Composite Adhesives (Under the direction of H. Thomas Banks). Thermally conductive composite adhesives are desirable in many industrial applications, including computers, microelectronics, machinery and appliances. These composite adhesives are formed when a filler particle of high conductivity is added to a base adhesive. Typically, adhesives are poor thermal conductors. Experimentally only small improvements in the thermal properties of the composite adhesives over the base adhesives have been observed. A thorough understanding of heat transfer through a composite adhesive would aid in the design of a thermally conductive composite adhesive that has the desired thermal properties.In this work, we study design methodologies for thermally conductive composite adhesives. We present a three dimensional model for heat transfer through a composite adhesive based on its composition and on the experimental method for measuring its thermal properties. For proof of concept, we reduce our model to a two dimensional model. We present numerical solutions to our two dimensional model based on a composite silicone and investigate the effect of the particle geometry on the heat flow through this composite. We also present homogenization theory as a tool for computing the ``effective thermal conductivity" of a composite material.We prove existence, uniqueness and continuous dependence theorems for our two dimensional model. We formulate a parameter estimation problem for the two dimensional model and present numerical results. We first estimate the thermal conductivity parameters as constants, and then use a probability based approach to estimate the parameters as realizations of random variables. A theoretical framework for the probability based approach is outlined.Based on the results of the parameter estimation problem, we are led to formally derive sensitivity equations for our system. We investigate the sensitivity of our composite silicone with respect to the thermal conductivity of both the base silicone polymer and the filler particles. Numerical results of this investigation are also presented.
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Norton, Kevin P. "Thermal analysis : applications in the geological sciences /." Connect to resource, 1997. http://hdl.handle.net/1811/24795.
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Mahfoud, Musbah. "Controlled thermal analysis using heat pipe technology." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34663.
Full textAbstract:
Thermal analysis is a non-destructive and quantitative technique used to assess the quality of the liquid metal prior to casting. The method has been used in the aluminum foundry to assess the extent of grain refining and the degree of eutectic modification. Although the method has been, to a certain extent, successfully used, it has some serious drawbacks. The most apparent include: (a) poor reproducibility, (b) poor control over heat extraction and cooling rates, (c) a batch operation, and (d) a manual operation which is difficult to automate and computerize.To overcome these shortcomings associated with current thermal analysis methods, a new technique of performing thermal analysis on aluminum alloys has been devised. Besides being semi-continuous, the new system is easier to use, more dependable and, most importantly, capable of performing thermal analysis tests at controlled and variable cooling rates throughout the entire solidification process.
The new thermal analysis technique is based on heat pipe principles in which a small quantity of a melt, residing in the core of a heat pipe probe, is solidified, and its cooling curve is acquired. Once the cooling curve has been acquired, the probe is instructed to remelt the sample and await instructions to run another test. The new probe, which resides in the melt and need not be withdrawn, is used to solidify the sample under predetermined and controlled conditions.
The operating principles of the new thermal analysis device are based on heat pipe technology. In simple terms, a heat pipe is a high heat transfer device capable of transferring large amounts of heat from a source to a sink by taking advantage of the high heat transfer rates associated with the evaporation and condensation of a working fluid placed inside the pipe. Heat is absorbed at the heat source (evaporator) and dissipated at the heat sink (condenser) at approximately isothermal conditions, and hence the thermal gradient from one extreme end of the pipe to the other is minimal, the amount of heat transferred is large, and the thermal resistance is small.
The new thermal analysis device has been used to produce cooling curves of various aluminum alloys. The device has also been shown to detect the extent of grain refinement, degree of eutectic modification, and formation of intermetallic phases. In addition, the device has been used to quantify the amount of iron in aluminum melts. Thermal analysis results obtained with the new technique are in good agreement with those of conventional thermal analysis. In conjunction with the new device, a control scheme has been devised to control the heat extraction and cooling rates during cooling of aluminum alloys. Finally, a heat transfer and solidification model of the heat pipe thermal analyzer is derived and validated based on the acquired experimental data.
Thermal analysis results are reported for pure aluminum, three casting alloys: hypeoeutectic aluminum silicon (A356 and A319), and a eutectic aluminum silicon (413) alloy, and a wrought alloy of the 6000 series (6061).
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Koetniyon, Saiprasit. "Thermal stress analysis of automotive disc brakes." Thesis, University of Leeds, 2000. http://etheses.whiterose.ac.uk/2938/.
Full textAbstract:
A brake disc rotor forms pan of a foundation brake and rotates with the wheel hub assembly. The main function of a foundation brake is to generate a retarding torque by converting mechanical energy to thermal energy by virtue of the frictional work done in relative sliding at the rotor-pad interface. In practice, most brake discs arc made from cast iron and in use arc sometimes subjected to high thermal stresses which can lead to permanent plastic deformation and occasionally rotor cracking. The aim of the present work is to investigate the thermal response of such a cast iron brake disc using the finite element (FE) method. One particular existing brake disc design for a medium passenger car was chosen for the investigation. This is a "back-vented" disc designed to minimise disc coning but the present work also includes an investigation of a conventional "frontvented" disc similar in dimension to the back-vented disc but with different detailed geometry. Experimental work was undertaken to derive the rotor material properties in tension and compression as a function of temperature. This data was used to generate suitable FE material model routines which accurately allow for the different temperature-dependent yield properties of cast iron in tension and compression. The modelling work highlights the role of the rotor geometry in controlling the thermal response of the structure but. more importantly, the necessity for an accurate material model is illustrated, particularly with regard to its ability to predict the accumulation of plastic strain which may lead to rotor cracking. Using the most accurate user developed material subroutine, the thermal response of the back-and front-vented disc designs are compared: the back-vented disc suffers lower thermal distortion but at the expense of higher plastic strain accumulation, particularly near the point of attachment of the vanes.
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Kuwn-Shung, Liu, and 劉坤孝. "Thermal and Thermal Stresses Analysis in Electronic Package." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/84880142711789735638.
Full textAbstract:
碩士國立雲林科技大學
機械工程技術研究所
86
The research describes how Finite Element Method(FEM) is used to simulate the temperature distribution of the electronic package under various environment condition. The thermal stresses due to material mismatch between different components of the package are also disscussed. The thermal model is built by FEM. The effects of various air speed on the thermal resistance of the package is studied too. Furthermore, Taguchi method is applied to find out the best combination of various geometric parameters to get the optimum thermal performance of the package.
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Recber, Ali Cem. "Thermal analysis of poly(desamino arylates) Thermal analysis of poly(desamino arylates)." Thesis, 2004. http://library1.njit.edu/etd/fromwebvoyage.cfm?id=njit-etd2004-120.
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江欣怡. "Structural Design and Thermal Analysis of Electro-Thermal Microactuator." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/73259538021729303447.
Full textAbstract:
碩士國立清華大學
動力機械工程學系
92
An actuator is a component of the Micro-Electro-Mechanical System (MEMS). The ways to drive actuators include electrostatic driving, piezoelectricity driving, electromagnetic driving, electro-thermal driving and shape memory alloy. Electro-thermal actuators have such advantages as lower input voltage needed, integrated-circuit manufacturing technology used. Furthermore, both types of actuators can be arrayed to increase its displacement and output force. Therefore, the actuators have sizable development space in application We choose curve-beam as the structure, because the structure can avoid horizontal buckle in the V-type actuators. A finite element software (ANSYS) was used to solve the 3D electro-thermo-mechanical problems. We compute the optimum dimension that has the maximum displacement and minimum stress. The optimum structure of actuator is 5μm wide and 3,000μm in radius. The structure materials include Silicon Substrate, Aluminum Pad and Polysilicon. The analysis processes are based on thermodynamics, so we can compute the accurate heat transfer coefficient and get accurate temperature distribution by using ANSYS. Then we can obtain accurate mechanical behaviors, and compare them with the literature. Its error is under 10%.
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Fu, Yu-Hsiu, and 傅裕修. "Thermal Conductivity and Sensitivity Analysis of Thermal Interface Material." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/63072920902327608273.
Full textAbstract:
碩士國立清華大學
工程與系統科學系
95
At present, all the heat dissipation elements used in computer would be include heat sink, fan or heat pipe etc. Strictly speaking, the Thermal Interface Material (T.I.M.) should be account into too. A good T.I.M. could reduce largely the thermal resistance between heat source and the heat sink. In order to obtain the optimal selection, we need to measure the thermo properties of the T.I.M. very accuracy. The purpose of this paper is to build up a very high sensitivity T.I.M. measuring system which was based on one-dimension heat transfer theory and the precise processing technology. This article includes four parts, the first one is to discuss the effect of the different thickness of the spacer to the sensitivity of the instrument, the second part and the third part was discussing the repeatability and the reproducibility respectively. The fourth part was used dummy heater developed by ECS laboratory to evaluate the thermo resistance value of the grease and double check was that consistence evaluate from T.I.M. instrument. The experiment results showed that the ABS spacer developed by ECS laboratory a very good sensitivity performance. The relative error of the conductivity coefficient from the repeatability experiment was within 5%, while the relative error for the contact resistance was within 10%. The relative error of the reproducibility made by different operator was control within 2%.
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GAURAV. "THERMO-ECONOMIC ANALYSIS OF A COMBINED CYCLE THERMAL POWER PLANT." Thesis, 2022. http://dspace.dtu.ac.in:8080/jspui/handle/repository/19299.
Full textAbstract:
Energy drives modern growth. All systems rely on it. Historiography shows that countries
with limited energy grow more slowly. Increase energy availability. Our nation is similar.
Too long, our nation has been energy-deficient. We must alter this. Scientists worldwide are
working to increase energy supplies. New energy-creation strategies are investigated
constantly. Globally, renewable energy development is accelerated. Researchers are reducing
reliance on fossil fuels for power. Sustainability of electricity production is also a concern. If
natural resources aren't used properly and effectively, they may become uneconomical.
Today, fossil-fueled thermal power plants produce much of the world's energy. To make the
process "sustainable," we must reduce our reliance on fossil fuels. Analysing existing thermal
power plants helps us find ways to enhance their efficiency. Increasing energy output per unit
of fuel should reduce capital and operational costs. This is the basis for
THERMOECONOMIC ANALYSIS OF POWER GENERATION SYSTEMS, especially
COMBINED CYCLE SYSTEMS (CCPP). This analysis addresses physical and intangible
costs and thermal power plant efficiency. As a system's operating temperature rises, its
thermodynamic efficiency improves. Many design aspects must be moved. This research
evaluates combined cycle power plant thermo-economics. Prior study provided temperature,
pressure, mass flow rate, work generated, and plant efficiency (which will be discussed in the
Literature Review). MATLAB/Simulink was used to simulate the power plant's segments and
subassemblies. These models are verified with CCPP data. Parametric study used the proven
model to predict plant performance.
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Wang, Jenq-Chyi, and 汪正祺. "Thermal stress analysis of semiconductor wafers in rapid thermal processing." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/88438136622610522548.
Full textAbstract:
碩士國立成功大學
機械工程學系
86
Thermal stresses are an important consideration in production processes involving large temperature changes. Recently, Thermal stresses have also become significant in semiconductors related to wafers. To calculate the thermal stresses, we analysis four kinds of boundary conditions. This article investigates the thermal stress in a 8 inch wafer with its surfaces subjected to heat radiation. In order to obtain the solution of the governing equation, which is a partial differential equation, the following procedures of analysis are used. 1. Normalize the governing partial differential equation of temperature subject to appropriate initial and boundary conditions. Use finite-difference method to transform the governing equation, initial and boundary conditions. 2. Normalize the governing partial differential equation of stress subject to appropriate initial and boundary conditions. 3. Substitute the temperature distribution into the governing equation of thermal stresses. Then use Simpson， s method to obtain the thermal stress distribution as a function of time and position of the wafer.
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Kao, Chuan-sheng, and 高川盛. "Thermal Analysis and Experiments on Thermal Management of LCD PC." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/00189591970324528943.
Full textAbstract:
碩士大同大學
機械工程學系(所)
96
Recently personal computers are getting more and more popular and it makes the accuracy thermal solution required constantly because more implement CPU with higher speed available in the market, in other words, all kinds of thermal solution and modules are amazing for users now. LCD PC is not only particular to be lighter and thinner but also more efficient than desktop and it is the reason why personal computer is more and more popular in the market, moreover, a sharply cost-down for large LCD panel which makes personal computers to be a trend and wide-spread eventually. Traditional LCD-PC normally is designed to be similar to desktop because of space limited, such like a big fan for heat-sink which leads the high temperature continuously surrounded in the system and can not makes thermal flow dispelled completely, however, most of end-customers request to have low-noise supported and this special request is against to force convection acutely. The main purpose of this essay is to discuss overall LCD PC thermal issues and to analyze different heat-sinks as well as the system temperature and airflow caused by various fan position by simulated software IcePak. We try to used final simulation system to verify, and get more beat perfection value. We try five different strategies in this case. The best thermal performance by using the CFD code will be compared with this case.
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Huang, Chieh-hsing, and 黃捷信. "Thermal Analysis and Experiments on Thermal Management of POS System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/92285693239347785999.
Full textAbstract:
碩士大同大學
機械工程學系(所)
100
With the rapid development of retail business in recent years, there are many warehouse stores, franchise stores and restaurants, which attempt to use computer to manage their merchandise. Except for the function of a traditional Electronic Cash Register (ECR), it also integrates with goods data management, customer data management, stock management and credit card consumption function now. In order to coordinate with related hardware, the operation speed of system is getting more and more important. In other words, wattage is getting higher too. For example, cash register, scanner, printer, monitor and so on. Point of sale (POS) device which has to possess excellent thermal management within a limited space is needed for outline size and protective level. Therefore, if heat dissipation is not designed correctly for high wattage systems, it will cause equipment instability, reduce machine lifetime and crash frequently. For these reasons, the thermal management design of electronics equipments is very important. The main purpose of this project is to focus on the thermal management research of POS device. A heat sink is designed for CPU placed in turbulent air flow. The shape of the heat sink is optimized to achieve sufficient cooling in forced convection heat transfer. The design is conducted in CAD modeler Pro/E. CFD simulation is conducted in Flotherm to study the heat transfer and fluid flow pattern around the heat sink and CPU temperature. Eventually, simulation data will be used for optimization the heat dissipation process of whole POS device system.
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Li, Meng-Zung, and 李孟哲. "Thermal Performance Analysis of A LEDProjector by Thermal Network Method." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/q4tkes.
Full textAbstract:
碩士國立臺灣海洋大學
機械與機電工程學系
106
Optical engine technology is getting more mature nowadays. The utilization of LED light sources has reached maximum. Since the conversion efficiency of the LED power goes higher, modern projectors are becoming more compact, compared with their big and heavy predecessors in the past. However, due to the strict limitations in the temperatures of LED sources, precision control of thermal and flow fields is essential, and it is also necessary to enhance heat dissipation rate in the projectors. In addition to compactness, shape plays another important role in attracting consumers. Ventholes though necessary, are usually not desirable. Therefore it is proposed to drill ventholes in the bottom face of the projector. Doing this, the design of the projector shape will be less limited and the products could be more attractive and popular. This study employs thermal resistance network method to develop the thermal model of the entire LED projector. Experiments associated with simulations are conducted in the first stage of work, where a commercial code ICEPAK is used. Experimental data are compared with the numerical results favorably. Cooling improvements and analyses of several representative cases are performed in the second stage of work. Thermal performance for each case is investigated by examining the total thermal resistance in the thermal resistance network. Numerical results dictate details of thermal and flow fields with emphasis on the impacts of locations of the inlet and the exits. Under one inlet condition, recirculation of waste heat appeared due to short distance between the inlet and the outlets. It is quite difficult to separate the inflow from the outflow within limited space in the projector. Therefore we chose to drill ventholes on the four sides of the bottom along with putting the fan in the center and removing the fan case. It was found that heated air flows out of the projector smoothly, and the high-temperature components cool down significantly along with some temperature increase in the low-temperature components. As such, the temperature field tends to be evenly distributed . Hence the difficulty in cooling due to setting ventholes on the bottom face has been resolved effectively.
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Huang, Han-Liang, and 黃瀚樑. "The reliability analysis of thermal conductivity measurement at Thermal Pad and Thermal insulated materials." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/80745736821406298480.
Full textAbstract:
碩士國立清華大學
工程與系統科學系
98
Abstract In order to reduce the thermal resistance contact from thermal modules and heat source, we need to use thermal interface material (Thermal Interface Material, TIM) to effectively remove the heat which is generated by the CPU and achieve the purpose of cooling. Developed in our laboratory, we establish a measurment system for the measurment of thermal interface materials. This system can accurately measure the properties of thermal interface materials. The main purpose of this paper is to gauge and analyze the thermal conductivity of thermal pad and insulation materials by using the TIM measurment system. Thermal conductivity analysis of insulation materials must be a very important basis of energy engineering in the future. The results can be found in the following experiments. The relative error of thermal conductivity’s repeatability were less than 1% when measuring Thermal Grease ( using Dow Coning TC-5121 and Shin-Etsu 7762 ) by TIM measurement system. When measuring 15 kinds of Thermal Pad’s thermal conductivity ( using 14 kinds of samples from the SAINT-GOBAIN Advanced Materials (Taiwan) Co.,Ltd and one from the TSC ).We can found that the relative error of repeatability and reproducibility were below 10%. As mentioned above, TIM measurement system has high stability and accuracy. Therefore, we use TIM measurement system to gauge and analyze the thermal conductivity of insulation materials. Measure and compare some materials, such as bakelite and teflon, which their thermal conductivity properties had been known. The experimental results shows that we control the thickness of insulation material below 1.5mm, the relative error of thermal conductivity which was gauged by the TIM measurement system, and the theoretical value will less than 10%. These results also indicated that this TIM measurement system have high stability and accuracy in measureing Thermal Pad and insulation materials.
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Huang, Yu-Chih, and 黃毓智. "Thermal Analysis for CSP Package." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/59072337292498895597.
Full textAbstract:
碩士國立成功大學
工程科學系
88
Due to that the electronic products will be smaller and smaller ,heat problems has been happened. High temperature would damage components of the packages and decreases the reliability of the electronic products. And temperature of CSP packages also has the relation with solder ball grid array and chip size etc. We use thermal network method analyzing the thermal performance of the CSP package. And we also find out the total thermal resistance and center temperature of the package. Then we changed some of the original parameter, material property, solder ball number etc. The results help us to prevent the failure of the package, and increase the reliability of the products.