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Latent Heat Thermal Energy Storage Device for Automobile ApplicationsShih, Po-Chen 28 November 2013 (has links)
Driving with the cold engine increases fuel consumption and greenhouse gases emissions. A latent heat energy storage device has been proposed to recover waste heat and reduce engine warm-up time by using phase change materials (PCMs) as an energy storage medium. Two types of paraffin waxes and 50/50 mixture of the two have been examined to characterize their behaviors under repetitive heating/freezing. From the results, the heat transfer is more effective in the case of narrower spacing distances between the cooling plates and high circulating flow rate of the heat transfer fluid. A 50/50 mixture of two paraffin waxes also provides better heat transfer due to the possible existence of both conduction and natural convection. The results of the metal block simulation experiments demonstrated the potential of latent heat TES’s for use in engine warm-up.
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Latent Heat Thermal Energy Storage Device for Automobile ApplicationsShih, Po-Chen 28 November 2013 (has links)
Driving with the cold engine increases fuel consumption and greenhouse gases emissions. A latent heat energy storage device has been proposed to recover waste heat and reduce engine warm-up time by using phase change materials (PCMs) as an energy storage medium. Two types of paraffin waxes and 50/50 mixture of the two have been examined to characterize their behaviors under repetitive heating/freezing. From the results, the heat transfer is more effective in the case of narrower spacing distances between the cooling plates and high circulating flow rate of the heat transfer fluid. A 50/50 mixture of two paraffin waxes also provides better heat transfer due to the possible existence of both conduction and natural convection. The results of the metal block simulation experiments demonstrated the potential of latent heat TES’s for use in engine warm-up.
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Potential of tall oil pitch as phase change material in lignin-shelled hybrid nanocapsules for thermal energy storage.Viberg Nissilä, Helena January 2022 (has links)
A prospect in utilizing thermal energy in development of energy systems is by the useof phase change materials (PCMs). PCMs are materials that can store and releaseenergy during phase changes, e.g. from solid to liquid. By-products from the woodand pulping industry could be of interest in this area, in part to add value to theby-products, enhance the yield of the raw product of wood and become less dependenton fossil based fuels. Capsules of lignin and tall oil pitch/tall oil fatty acids weresuccessfully produced with a straightforward coprecipitation method. The solventused was acetone and the antisolvent was distilled water. Dynamic light scatteringanalysis showed average particle diameters of 300 to 500 nm and fairly lowpolydispersity, between 0.2 to 0.3, indicating spherical particles. Scanning electronmicroscopy confirmed particle size and the formation of capsules with shell thicknessless than 100 nm. The particle dispersions showed sufficiently high zeta potential tomaintain a stable colloidal system. Thermal analysis confirmed stability in atemperature range of at least -40 °C to +50 °C, and resistance to decomposition at leastup to around 200 °C. There were also indications of enhanced thermal stability of talloil pitch due to encapsulation. A desired feature for a phase change material is theability to keep a constant temperature during phase change. Regarding using thesynthesized material as phase change material, the results show that the temperaturerange in which phase change, such as melting, occurs is too broad. Latent heat of fusionof 4.7 J/g for the material is also very low compared with commercial phase changematerials. Further studies in modifying the system to impact melting point andenhancement of latent heat is needed if the material should be applicable as an efficientand competitive phase change material.
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High-Capacity Cool Thermal Energy Storage for Peak Shaving - a Solution for Energy Challenges in the 21st centuryHe, Bo January 2004 (has links)
Due to climatic change, increasing thermal loads inbuildings and rising living standards, comfort cooling inbuildings is becoming increasingly important and the demand forcomfort cooling is expanding very quickly around the world. Theincreased cooling demand results in a peak in electrical powerdemand during the hottest summer hours. This peak presents newchallenges and uncertainties to electricity utilities and theircustomers. Cool thermal storage systems have not only the potential tobecome one of the primary solutions to the electrical powerimbalance between production and demand, but also shift coolingenergy use to off-peak periods and avoid peak demand charges.It increases the possibilities of utilizing renewable energysources and waste heat for cooling generation. In addition, acool storage can actually increase the efficiency of combinedheat and power (CHP) generation provided that heat drivencooling is coupled to CHP. Then, the cool storage may avoidpeaks in the heat demand for cooling generation, and this meansthat the CHP can operate at design conditions in most oftime. Phase Change Materials (PCMs) used for cool storage hasobtained considerable attention, since they can be designed tomelt and freeze at a selected temperature and have shown apromising ability to reduce the size of storage systemscompared with a sensible heat storage system because they usethe latent heat of the storage medium for thermal energystorage. The goal of this thesis is to define suitable PCM candidatesfor comfort cooling storage. The thesis work combines differentmethods to determine the thermophysical properties oftetradecane, hexadecane and their binary mixtures, anddemonstrates the potential of using these materials as PCM forcomfort cooling storage. The phase equilibrium of the binarysystem has been studied theoretically as well asexperimentally, resulting in the derivation of the phasediagram. With knowledge of the liquid-solid phase equilibriumcharacteristics and the phase diagram, an improvedunderstanding is provided for the interrelationships involvedin the phase change of the studied materials. It has beenindicated that except for the minimum-melting point mixture,all mixtures melt and freeze within a temperature range and notat a constant temperature, which is so far often assumed in PCMstorage design. In addition, the enthalpy change during thephase transition (heat of fusion) corresponds to the phasechange temperature range; thus, the storage density obtaineddepends on how large a part of the phase change temperaturerange is valid for a given application. Differential Scanning Calorimetery (DSC) is one frequentlyused method in the development of PCMs. In this thesis, it hasbeen found that varying results are obtained depending on theDSC settings throughout the measurements. When the DSC runs ata high heating/cooling rate it will lead to erroneousinformation. Also, the correct phase transition temperaturerange cannot be obtained simply from DSC measurement. Combiningphase equilibrium considerations with DSC measurements gives areliable design method that incorporates both the heat offusion and the phase change temperature range. The potential of PCM storage for peak shaving in differentcooling systems has been demonstrated. A Computer model hasbeen developed for rapid phase equilibrium calculation. The useof phase equilibrium data in the design of a cool storagesystem is presented as a general methodology. Keywords:Comfort cooling, peak shaving, PCM, coolthermal storage system, DSC, phase change temperature range,the heat of fusion, phase equilibrium, phase diagram. Language:English
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High-Capacity Cool Thermal Energy Storage for Peak Shaving - a Solution for Energy Challenges in the 21st centuryHe, Bo January 2004 (has links)
<p>Due to climatic change, increasing thermal loads inbuildings and rising living standards, comfort cooling inbuildings is becoming increasingly important and the demand forcomfort cooling is expanding very quickly around the world. Theincreased cooling demand results in a peak in electrical powerdemand during the hottest summer hours. This peak presents newchallenges and uncertainties to electricity utilities and theircustomers.</p><p>Cool thermal storage systems have not only the potential tobecome one of the primary solutions to the electrical powerimbalance between production and demand, but also shift coolingenergy use to off-peak periods and avoid peak demand charges.It increases the possibilities of utilizing renewable energysources and waste heat for cooling generation. In addition, acool storage can actually increase the efficiency of combinedheat and power (CHP) generation provided that heat drivencooling is coupled to CHP. Then, the cool storage may avoidpeaks in the heat demand for cooling generation, and this meansthat the CHP can operate at design conditions in most oftime.</p><p>Phase Change Materials (PCMs) used for cool storage hasobtained considerable attention, since they can be designed tomelt and freeze at a selected temperature and have shown apromising ability to reduce the size of storage systemscompared with a sensible heat storage system because they usethe latent heat of the storage medium for thermal energystorage.</p><p>The goal of this thesis is to define suitable PCM candidatesfor comfort cooling storage. The thesis work combines differentmethods to determine the thermophysical properties oftetradecane, hexadecane and their binary mixtures, anddemonstrates the potential of using these materials as PCM forcomfort cooling storage. The phase equilibrium of the binarysystem has been studied theoretically as well asexperimentally, resulting in the derivation of the phasediagram. With knowledge of the liquid-solid phase equilibriumcharacteristics and the phase diagram, an improvedunderstanding is provided for the interrelationships involvedin the phase change of the studied materials. It has beenindicated that except for the minimum-melting point mixture,all mixtures melt and freeze within a temperature range and notat a constant temperature, which is so far often assumed in PCMstorage design. In addition, the enthalpy change during thephase transition (heat of fusion) corresponds to the phasechange temperature range; thus, the storage density obtaineddepends on how large a part of the phase change temperaturerange is valid for a given application.</p><p>Differential Scanning Calorimetery (DSC) is one frequentlyused method in the development of PCMs. In this thesis, it hasbeen found that varying results are obtained depending on theDSC settings throughout the measurements. When the DSC runs ata high heating/cooling rate it will lead to erroneousinformation. Also, the correct phase transition temperaturerange cannot be obtained simply from DSC measurement. Combiningphase equilibrium considerations with DSC measurements gives areliable design method that incorporates both the heat offusion and the phase change temperature range.</p><p>The potential of PCM storage for peak shaving in differentcooling systems has been demonstrated. A Computer model hasbeen developed for rapid phase equilibrium calculation. The useof phase equilibrium data in the design of a cool storagesystem is presented as a general methodology.</p><p><b>Keywords:</b>Comfort cooling, peak shaving, PCM, coolthermal storage system, DSC, phase change temperature range,the heat of fusion, phase equilibrium, phase diagram. Language:English</p>
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CMOS Integrated Resonators and Emerging Materials for MEMS ApplicationsJackson Anderson (16551828) 18 July 2023 (has links)
<p>With the advent of increasingly complex radio systems at higher frequencies and the slowing of traditional CMOS process scaling with power concerns, there has been an increased focus on integration, architectural, and material innovations as a continued path forward in MEMS and logic. This work presents the first comprehensive experimental study of resonant body transistors in a commercial 14nm FinFET process, demonstrating differential radio frequency transduction as a function of transistor biasing through electrostatic, piezoresistive, and threshold voltage modulation. The impact of device design changes on unreleased resonator performance are further explored, highlighting the importance of phononic confinement in achieving an f*Q product of 8.2*10<sup>11</sup> at 11.73 GHz. Also shown are initial efforts towards the understanding of coupled oscillator architectures and a perovskite nickelate material system. Finally, development of resonators based on two-dimensional materials, whose scale is particularly attractive for high-frequency nano-mechanical resonators and acoustic devices, is discussed. Experiments towards dry transfer of tellurene flakes using geometries printed via two photon polymerization are presented along with optimization of a fabrication process for gated RF devices, presenting new opportunities for high-frequency electro-mechanical interactions in this topological material. </p>
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Assessment of Thermally Enhanced Geo-Energy Piles and WallsElkezza, Omar A.A. January 2023 (has links)
Geo-energy piles and walls have long been recognized as a promising way to reduce carbon dioxide emissions while providing renewable energy. However, enhancing the thermal performance of these structures has remained a signif-icant challenge. This thesis evaluated five different approaches to improving the thermal performance of geo-energy piles and walls, through a series of experiments using a fully instrumented testing rig. The first approach involved adding graphTHERM powder to concrete to double its thermal conductivity, boosting heat transfer efficiency by an impressive 50% to 66%. The second approach tested slag-based geopolymer concrete as a sustainable construc-tion material for geo-energy piles and walls, reducing CO2 emissions by 44.5% while improving thermal performance by 14% to 21%. The third approach in-volved testing thermally enhanced soils at the geo-energy structures/soil inter-face, resulting in an 81% improvement in heat transfer efficiency. The fourth approach utilized innovative phase change material (PCM) heat exchangers that increased heat transfer efficiency by 75% and 43% in heating and cooling operations, respectively. Finally, incorporated PCM-impregnated light weight aggregates at the interface of the structure soil, significantly increasing tem-perature difference and reducing thermal deformation of geo-energy struc-tures.Overall, these innovative approaches made a significant contribution to enhancing the thermal performance of geo-energy piles and walls. However, approaches four and five, which involve utilizing PCM heat exchangers and PCM-impregnated LWA's, respectively, showed extra benefits in dropping the thermal effect on soils and reducing the thermal damage on those structures. These techniques offer great promise for improving the thermal performance of geo-energy structures.
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Thermal energy storage in metallic phase change materialsKotze, Johannes Paulus 12 1900 (has links)
Thesis (PhD) -- Stellenbosch University, 2014. / ENGLISH ABSTRACT: Currently the reduction of the levelised cost of electricity (LCOE) is the main goal of concentrating solar power (CSP) research. Central to a cost reduction strategy proposed by the American Department of Energy is the use of advanced power cycles like supercritical steam Rankine cycles to increase the efficiency of the CSP plant. A supercritical steam cycle requires source temperatures in excess of 620°C, which is above the maximum storage temperature of the current two-tank molten nitrate salt storage, which stores thermal energy at 565°C. Metallic phase change materials (PCM) can store thermal energy at higher temperatures, and do not have the drawbacks of salt based PCMs. A thermal energy storage (TES) concept is developed that uses both metallic PCMs and liquid metal heat transfer fluids (HTF). The concept was proposed in two iterations, one where steam is generated directly from the PCM – direct steam generation (DSG), and another where a separate liquid metal/water heat exchanger is used – indirect steam generation, (ISG). Eutectic aluminium-silicon alloy (AlSi12) was selected as the ideal metallic PCM for research, and eutectic sodium-potassium alloy (NaK) as the most suitable heat transfer fluid.
Thermal energy storage in PCMs results in moving boundary heat transfer problems, which has design implications. The heat transfer analysis of the heat transfer surfaces is significantly simplified if quasi-steady state heat transfer analysis can be assumed, and this is true if the Stefan condition is met. To validate the simplifying assumptions and to prove the concept, a prototype heat storage unit was built. During testing, it was shown that the simplifying assumptions are valid, and that the prototype worked, validating the concept. Unfortunately unexpected corrosion issues limited the experimental work, but highlighted an important aspect of metallic PCM TES. Liquid aluminium based alloys are highly corrosive to most materials and this is a topic for future investigation.
To demonstrate the practicality of the concept and to come to terms with the control strategy of both proposed concepts, a storage unit was designed for a 100 MW power plant with 15 hours of thermal storage. Only AlSi12 was used in the design, limiting the power cycle to a subcritical power block. This demonstrated some practicalities about the concept and shed some light on control issues regarding the DSG concept. A techno-economic evaluation of metallic PCM storage concluded that metallic PCMs can be used in conjunction with liquid metal heat transfer fluids to achieve high temperature storage and it should be economically viable if the corrosion issues of aluminium alloys can be resolved. The use of advanced power cycles, metallic PCM storage and liquid metal heat transfer is only merited if significant reduction in LCOE in the whole plant is achieved and only forms part of the solution. Cascading of multiple PCMs across a range of temperatures is required to minimize entropy generation. Two-tank molten salt storage can also be used in conjunction with cascaded metallic PCM storage to minimize cost, but this also needs further investigation. / AFRIKAANSE OPSOMMING: Tans is die minimering van die gemiddelde leeftydkoste van elektrisiteit (GLVE) die hoofdoel van gekonsentreerde son-energie navorsing. In die kosteverminderingsplan wat voorgestel is deur die Amerikaanse Departement van Energie, word die gebruik van gevorderde kragsiklusse aanbeveel. 'n Superkritiese stoom-siklus vereis bron temperature hoër as 620 °C, wat bo die 565 °C maksimum stoor temperatuur van die huidige twee-tenk gesmelte nitraatsout termiese energiestoor (TES) is. Metaal fase veranderingsmateriale (FVMe) kan termiese energie stoor by hoër temperature, en het nie die nadele van soutgebaseerde FVMe nie. ʼn TES konsep word ontwikkel wat gebruik maak van metaal FVM en vloeibare metaal warmteoordrag vloeistof. Die konsep is voorgestel in twee iterasies; een waar stoom direk gegenereer word uit die FVM (direkte stoomopwekking (DSO)), en 'n ander waar 'n afsonderlike vloeibare metaal/water warmteruiler gebruik word (indirekte stoomopwekking (ISO)). Eutektiese aluminium-silikon allooi (AlSi12) is gekies as die mees geskikte metaal FVM vir navorsingsdoeleindes, en eutektiese natrium – kalium allooi (NaK) as die mees geskikte warmteoordrag vloeistof.
Termiese energie stoor in FVMe lei tot bewegende grens warmteoordrag berekeninge, wat ontwerps-implikasies het. Die warmteoordrag ontleding van die warmteruilers word aansienlik vereenvoudig indien kwasi-bestendige toestand warmteoordrag ontledings gebruik kan word en dit is geldig indien daar aan die Stefan toestand voldoen word. Om vereenvoudigende aannames te bevestig en om die konsep te bewys is 'n prototipe warmte stoor eenheid gebou. Gedurende toetse is daar bewys dat die vereenvoudigende aannames geldig is, dat die prototipe werk en dien as ʼn bevestiging van die konsep. Ongelukkig het onverwagte korrosie die eksperimentele werk kortgeknip, maar dit het klem op 'n belangrike aspek van metaal FVM TES geplaas. Vloeibare aluminium allooie is hoogs korrosief en dit is 'n onderwerp vir toekomstige navorsing.
Om die praktiese uitvoerbaarheid van die konsep te demonstreer en om die beheerstrategie van beide voorgestelde konsepte te bevestig is 'n stoor-eenheid ontwerp vir 'n 100 MW kragstasie met 15 uur van 'n TES. Slegs AlSi12 is gebruik in die ontwerp, wat die kragsiklus beperk het tot 'n subkritiese stoomsiklus. Dit het praktiese aspekte van die konsep onderteken, en beheerkwessies rakende die DSO konsep in die kollig geplaas. In 'n tegno-ekonomiese analise van metaal FVM TES word die gevolgtrekking gemaak dat metaal FVMe gebruik kan word in samewerking met 'n vloeibare metaal warmteoordrag vloeistof om hoë temperatuur stoor moontlik te maak en dat dit ekonomies lewensvatbaar is indien die korrosie kwessies van aluminium allooi opgelos kan word. Die gebruik van gevorderde kragsiklusse, metaal FVM stoor en vloeibare metaal warmteoordrag word net geregverdig indien beduidende vermindering in GLVE van die hele kragsentrale bereik is, en dit vorm slegs 'n deel van die oplossing. ʼn Kaskade van verskeie FVMe oor 'n reeks van temperature word vereis om entropie generasie te minimeer. Twee-tenk gesmelte soutstoor kan ook gebruik word in samewerking met kaskade metaal FVM stoor om koste te verminder, maar dit moet ook verder ondersoek word.
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Comparação de modelos numéricos de malha fixa baseados em entalpia para os processos de fusão e de solidificação de PCM em esferaEhms, José Henrique Nazzi 31 October 2018 (has links)
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Previous issue date: 2018-10-31 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Armazenamento térmico apresenta grande potencial de utilização em diversas aplicações, como energia solar, climatização, conservação de alimentos ou aproveitamento de calor residual em processos industriais. O armazenamento térmico de calor latente é realizado com materiais de mudança de fase (PCM), através dos processos de fusão e solidificação. A representação destes processos através de simulação numérica é realizada com o acréscimo ao modelo matemático básico, composto pelas equações da conservação da massa, quantidade de movimento e energia, modelos para descrever o calor latente e a transição na velocidade entre as fases, tais como: Darcy STM (source term method), VVM (variable viscosity method) e SOM (switch-off method). No entanto, a grande maioria das pesquisas nesta área utiliza o primeiro método. Além disso, são poucos os estudos comparativos de diferentes métodos para descrever processos de mudança de fase. Assim, o objetivo do presente estudo é comparar os métodos Darcy STM, VVM e misto (utilizando elementos dos dois anteriores) na simulação numérica de processos de fusão e de solidificação do PCM RT27 no interior de uma esfera. O estudo foi realizado utilizando-se fluidodinâmica computacional, através do método dos volumes finitos. O Modelo numérico foi validado com resultados experimentais da literatura. Os resultados quantitativos e qualitativos de fração líquida mostram que o método Darcy STM é mais adequado ao processo de solidificação, enquanto o método VVM produz resultados mais próximos aos experimentais no processo de fusão. O custo computacional foi menor para o método Darcy STM e maior para o método VVM, enquanto o método misto apresenta custo computacional pouco inferior ao do método VVM. Na análise da camada líquida na fusão de contato, foram analisadas a velocidade descendente do sólido, a espessura da camada e a vazão na camada. Os resultados referentes a camada líquida indicaram significativa influência das configurações do método Darcy STM. No entanto, são pouco influenciados pelas configurações do método VVM. / Thermal energy storage presents great potential of utilization in several applications, such as solar energy, HVAC systems, food conservation or waste heat recovery in industrial processes. Latent heat thermal energy storage is realized with phase change materials (PCM), through solidification and melting processes. Representation of such processes through numerical simulation is performed with the addition to the basic numerical model, composed of the conservation equations of mass, momentum and energy, models to account the latent heat and the velocity transition between the phases, such as: Darcy STM (source term method), VVM (variable viscosity method) and SOM (switch-off method). However, the large majority of the research on such area employ the first method. Besides that, there are few comparative studies of different methods to describe phase change processes. Thus, the objective of the present work is compare Darcy STM, VVM and mixed method (using elements of the two prior) in the simulation of melting and solidification processes of PCM RT27 inside a sphere. The study was realized using computational fluid dynamics, with the finite volume method. The numerical model was validated with experimental results from literature. Quantitative and qualitative results of liquid fraction show that Darcy STM is most suitable to solidification process, while VVM produces results closer to experimental in the melting process. Computational cost was smaller for Darcy STM and greater for VVM, while mixed method presents computational cost slightly lower than the one of VVM. In the analysis of the liquid layer in close contact melting, were analyzed descending velocity of the solid, liquid layer thickness and the flow in the liquid layer. The results regarding the liquid layer denote significant influence of the configurations for Darcy STM. However, such results are little influenced by the configurations of VVM.
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Funcionalización de textiles mediante la aplicación de grafenoRuiz Calleja, Tamara Rocío 10 January 2022 (has links)
Tesis por compendio / [ES] La funcionalización de tejidos permite dotar a estos de nuevas propiedades que no poseen de forma inherente. Por su parte, el grafeno presenta excelentes características en cuanto a conductividad térmica y eléctrica, resistencia y flexibilidad. En esta tesis se evalúa la aplicación de grafeno sobre diferentes sustratos textiles para obtener tejidos capaces de conducir la electricidad y responder a estímulos térmicos, bien disipando el calor o bien transformando una corriente eléctrica en un incremento de temperatura en su superficie. Para ello, se aplica grafeno empleando diferentes métodos recubrimiento con rasqueta e impregnación sobre tejidos de celulosa y de poliéster. En primer lugar, destaca la influencia que ejerce la estructura del tejido sobre la resistencia eléctrica del recubrimiento, dando como resultado que aquellos tejidos con mayor coeficiente de ligadura son los que mejores resultados presentan al tener una superficie más homogénea en la que se deposita el recubrimiento. Asimismo, se halla que la incorporación de materiales de cambio de fase en el recubrimiento con grafeno permite una mayor disipación de calor cuando se calienta el tejido. Además, se consigue calefactar las muestras empleadas utilizando diferentes voltajes eléctricos lo que, a su vez, sirve para evaluar los defectos del recubrimiento analizando las imágenes termográficas. Entre otros hallazgos relevantes también cabe destacar la influencia que ejerce la humedad del sustrato sobre la resistencia eléctrica del grafeno y la importancia del curado térmico de las resinas para asegurar una buena solidez a los lavados. / [CA] La funcionalización de teixits permet dotar a aquests de noves propietats que no posseeixen de manera inherent. Per part seua, el grafé presenta excel·lents propietats quant a conductivitat tèrmica i elèctrica, resistència i flexibilitat. En aquesta tesi s'avalua l'aplicació de grafé sobre diferents substrats tèxtils per a obtindre teixits capaços de conduir l'electricitat i respondre a estímuls tèrmics, bé dissipant la calor o bé transformant un corrent elèctric en un increment de temperatura en la seua superfície. Per a això, s'aplica grafé emprant recobriment amb rasqueta i estampat sobre teixits de cel·lulosa i de polièster. En primer lloc, destaca la influència que exerceix l'estructura del teixit sobre la resistència elèctrica del recobriment, obtenint que aquells teixits amb major coeficient de lligadura són els que millors resultats presenten en tindre una superfície més homogènia en la qual es deposita el recobriment. Així mateix, es troba que la incorporació de materials de canvi de fase en el recobriment amb grafé permet una major dissipació de calor quan es calfa el teixit. A més, s'aconsegueix calefactar les mostres emprades utilitzant diferents voltatges elèctrics el que, al seu torn, serveix per a avaluar els defectes del recobriment analitzant les imatges termogràfiques. Entre altres troballes rellevants també cal destacar la influència que exerceix la humitat del substrat sobre la resistència del grafé i la importància del curat tèrmic de les resines per a assegurar una bona solidesa a les rentades. / [EN] Fabrics functionalization provides them with new properties that they do not inherently possess. Furthermore, graphene has excellent characteristics in terms of thermal and electrical conductivity, resistance, and flexibility. In this thesis, the application of graphene on different textile substrates is evaluated to obtain fabrics capable of conducting electricity and responding to thermal stimuli, either by dissipating heat or by transforming an electrical current into an increase in surface temperature. For this purpose, graphene is applied using knife-coating and screen-printing on cellulose and polyester fabrics. First of all, it is worth highlighting the influence exerted by the structure of the fabric on the electrical resistance of the coating, obtaining that those fabrics with the highest interlacing coefficient are the ones that present the best results as they have a more homogeneous surface on which the coating is deposited. Also, it is found that the incorporation of phase change materials in the coating containing graphene allows for greater heat dissipation when the fabric is heated. In addition, it is possible to heat the samples using different electrical voltages, which also serves to evaluate the defects of the coating by analyzing the thermographic images. Among other relevant findings, it is also worth highlighting the influence that substrate humidity exerts on the resistance of graphene and the importance of thermal curing of the resins to ensure good washing fastness. / Ruiz Calleja, TR. (2021). Funcionalización de textiles mediante la aplicación de grafeno [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/179634 / TESIS / Compendio
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