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Estudo numerico da solidificação em geometria anular / Numerical study of solidification in annular geometryJesus, Antonio Batista de 27 April 1998 (has links)
Orientador: Kamal Abdel Radi Ismail / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-24T15:15:51Z (GMT). No. of bitstreams: 1
Jesus_AntonioBatistade_M.pdf: 6229768 bytes, checksum: 61cd2624ecc0457d83d065bb7385e84a (MD5)
Previous issue date: 1998 / Resumo: O processo de solidificação de um material de mudança de fase em região anular ao redor de um cilindro resfriado pela passagem de um fluido em seu interior é estudado numericamente com vistas à aplicação em sistemas de armazenamento de calor latente. A solução do problema de mudança de fase é feita utilizando a técnica de imobilização de fronteira, onde aplica-se uma transformação de coordenadas, de maneira que no novo sistema a fronteira móvel e irregular seja fixa e paralela às demais. A condução de calor no material de mudança de fase é acoplada à condução na parede do cilindro e à convecção no interior deste. O método de volumes finitos é utilizado para a discretização das equações do modelo matemático que são em seguida resolvidas computacionalmente. São analisados aspectos relativos à implementação da técnica de imobilização, como o surgimento de termos pseudo-convectivos e pesudo-anisotrópicos por conseqüência da mudança de variáveis. Também são estudados aspectos relacionados com o acoplamento da condução de calor no cilindro e no material de mudança de fase e a convecção no fluido refrigerante. São apresentadas comparações com outros trabalhos da literatura e um conjunto de resultados para o caso de água como material de mudança de fase / Abstract: Solidification of a phase-change material in an annulus around a cylinder, which carries inside it a coolant fluid, is studied numerically for application in latent heat thermal energy storage. The boundaryimmobilization technique is used for solving the phase-change problem. A coordinate transformation is performed so that in the new system the moving and irregular boundary becomes fixed and parallel to the others. Heat conduction in the phase-change material is coupled with conduction in the inner tube wall and convection in the coolant. The fmite-volume methodology is used for discretization of the equations from the mathematical model which are then solved by a computer programo Some aspects related with the application of the boundaryimmobilization technique are analyzed such as the appearance of pseudo-convective and pseudo-anisotropic terms as a consequence of the change of variables. Aspects related to the coupling of conduction ill the cylinder wall and phase-change material with convection in the coolant fluid are also studied. Comparisons with other solutions available in the literature are presented as well results for the specific case of water being the phasechange material / Mestrado / Termica e Fluidos / Mestre em Engenharia Mecânica
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Energy storage in phase change materials in cylindrical containersMenon, Anilkumar S. January 1981 (has links)
No description available.
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Salz/Zeolith-Komposite für die Sorptionswärmespeicherung / Salt/Zeolite Composites for Sorption Heat StorageNonnen, Thomas 01 August 2016 (has links) (PDF)
Zeolithgranulate sind etablierte Materialien für die Speicherung von Wärme mittels Wassersorption. Eine Erhöhung der Wärmespeicherdichte des Granulats ist durch Kombination mit hygroskopischen Salzen wie Calciumchlorid, Magnesiumchlorid oder Magnesiumsulfat möglich. In der vorliegenden Dissertation wird gezeigt, dass die Wär-mespeichereigenschaften derartiger Komposite von der Deliqueszenzluftfeuchte des Salzes, von der Salzbeladung und von der Luftfeuchte bei der Wassersorption abhängen. Liegt die Luftfeuchte unterhalb der Deliqueszenzluftfeuchte des Salzes, so nehmen Was-serbeladungshub, Wärmespeicherdichte und thermische Leistung mit steigender Salz-beladung um bis zu 71 % ab. Dies wird darauf zurückgeführt, dass Salzionen in die Mik-roporen des Zeoliths inkludiert werden und das für die Wassersorption zur Verfügung stehende Volumen verringern. Unterhalb der Deliqueszenzluftfeuchte ist das einge-brachte Salz daher thermochemisch inaktiv. Oberhalb der Deliqueszenzluftfeuchte und oberhalb einer salz- und luftfeuchteabhängigen Mindestsalzbeladung kommt es zur Ausbildung einer Salzlösung im Sekundärporensystem des Granulats. Die Absorption von Wasserdampf in der Salzlösung führt gegenüber dem salzfreien Granulat zu einer Steigerung von Wasserbeladungshub und Wärmespeicherdichte um bis zu 53 %. Dies geht jedoch einher mit einer Verringerung der thermischen Leistung um bis zu 50 %. Die Hydratation von kristallinem Salz im Granulat spielt gegenüber Salzinklusion und Ausbildung der Salzlösung nur eine untergeordnete Rolle. Die aus den experimentellen Befunden abgeleiteten Erkenntnisse konnten in ein semiempirisches mathematisches Modell überführt werden, welches den Wasserbeladungshub der Komposite quantitativ beschreibt. / Zeolite beads are established materials for the storage of heat by water sorption. An increase of the heat storage density of the beads is possible via the combination with hygroscopic salts. In this thesis it is shown, that the heat storage properties of compo-sites of this kind depend in a complex manner on the deliquescence humidity of the salt, on the salt loading, and on the humidity during water sorption. When the humidity is below the deliquescence humidity of the salt, water loading lift, heat storage density, and thermal power are reduced by up to 71 % with increasing salt content. This is at-tributed to the inclusion of salt into the micropores of the zeolite and the reduction of the volume available for the sorption of water. Thus, below the deliquescence humidity, the salt is thermochemically inactive. Above the deliquescence humidity and above a salt- and humidity-dependend minimum salt loading, a salt solution is formed in the secondary pore system of the beads. The absorption of water vapor in the salt solution gives rise to an increase of the water loading lift and of the heat storage density by up to 53 %, compared to the salt-free zeolite beads. However, this is accompanied by a reduc-tion of the thermal power output by up to 50 %. The hydration of crystalline salt in the beads is only of minor importance for the composites. The findings from the experi-mental work were transferred into a semi-empirical mathematical model, which de-scribes the water loading lift of the composites.
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Salz/Zeolith-Komposite für die SorptionswärmespeicherungNonnen, Thomas 28 June 2016 (has links)
Zeolithgranulate sind etablierte Materialien für die Speicherung von Wärme mittels Wassersorption. Eine Erhöhung der Wärmespeicherdichte des Granulats ist durch Kombination mit hygroskopischen Salzen wie Calciumchlorid, Magnesiumchlorid oder Magnesiumsulfat möglich. In der vorliegenden Dissertation wird gezeigt, dass die Wär-mespeichereigenschaften derartiger Komposite von der Deliqueszenzluftfeuchte des Salzes, von der Salzbeladung und von der Luftfeuchte bei der Wassersorption abhängen. Liegt die Luftfeuchte unterhalb der Deliqueszenzluftfeuchte des Salzes, so nehmen Was-serbeladungshub, Wärmespeicherdichte und thermische Leistung mit steigender Salz-beladung um bis zu 71 % ab. Dies wird darauf zurückgeführt, dass Salzionen in die Mik-roporen des Zeoliths inkludiert werden und das für die Wassersorption zur Verfügung stehende Volumen verringern. Unterhalb der Deliqueszenzluftfeuchte ist das einge-brachte Salz daher thermochemisch inaktiv. Oberhalb der Deliqueszenzluftfeuchte und oberhalb einer salz- und luftfeuchteabhängigen Mindestsalzbeladung kommt es zur Ausbildung einer Salzlösung im Sekundärporensystem des Granulats. Die Absorption von Wasserdampf in der Salzlösung führt gegenüber dem salzfreien Granulat zu einer Steigerung von Wasserbeladungshub und Wärmespeicherdichte um bis zu 53 %. Dies geht jedoch einher mit einer Verringerung der thermischen Leistung um bis zu 50 %. Die Hydratation von kristallinem Salz im Granulat spielt gegenüber Salzinklusion und Ausbildung der Salzlösung nur eine untergeordnete Rolle. Die aus den experimentellen Befunden abgeleiteten Erkenntnisse konnten in ein semiempirisches mathematisches Modell überführt werden, welches den Wasserbeladungshub der Komposite quantitativ beschreibt. / Zeolite beads are established materials for the storage of heat by water sorption. An increase of the heat storage density of the beads is possible via the combination with hygroscopic salts. In this thesis it is shown, that the heat storage properties of compo-sites of this kind depend in a complex manner on the deliquescence humidity of the salt, on the salt loading, and on the humidity during water sorption. When the humidity is below the deliquescence humidity of the salt, water loading lift, heat storage density, and thermal power are reduced by up to 71 % with increasing salt content. This is at-tributed to the inclusion of salt into the micropores of the zeolite and the reduction of the volume available for the sorption of water. Thus, below the deliquescence humidity, the salt is thermochemically inactive. Above the deliquescence humidity and above a salt- and humidity-dependend minimum salt loading, a salt solution is formed in the secondary pore system of the beads. The absorption of water vapor in the salt solution gives rise to an increase of the water loading lift and of the heat storage density by up to 53 %, compared to the salt-free zeolite beads. However, this is accompanied by a reduc-tion of the thermal power output by up to 50 %. The hydration of crystalline salt in the beads is only of minor importance for the composites. The findings from the experi-mental work were transferred into a semi-empirical mathematical model, which de-scribes the water loading lift of the composites.
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A method for determining the installed capacity of an underfloor electrical resistance heating and energy storage systemSmith, Carol Elaine. January 1985 (has links)
Call number: LD2668 .T4 1985 S64 / Master of Science
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Performance of a solar air heater incorporating thermal storageLombaard, Francois 12 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: In the present study, research was conducted to determine the
feasibility of water energy storage through which the output of
heated air by an upward facing solar air heater could be prolonged.
Following a systematic approach, a number of experimental test
swere initially performed on an upward facing solar air heater in
order to obtain a benchmark that could be used to evaluate the
influence of water storage during the day-time performance of a
solar air heater. As expected, an increase in the air mass flow rate
not only led to an increase in the collector efficiency but also to a
decrease in the temperature gain across the collector. In addition,
a number of day- and night-time experiments were executed on a
plastic covered water tank in order to evaluate it's ability to store
and discharge thermal energy. Results clearly indicated that the
plastic covered water tank was both an ideal collector and storage
medium of solar energy. Experimental results also revealed that
the plastic covered water tank was an ideal source of thermal
energy for a solar air heater during night-time operation.
Subsequently, both day- and night-time experiments were
performed on an upward facing solar air heater in which plastic
covered water tanks were installed. Day-time experimental results
revealed that the modified solar air heater still had the same
collector efficiency tendency, as observed in the initial solar air
heater experiments, but that the water energy storage led to a
dramatic decrease in the absorber plate temperature and in the
corresponding temperature gain experienced across the collector.
In contrast, the night-time operation results clearly indicated that
the water energy storage was not only able to prolong the output of
heated air by the solar air heater, but was further able to increase
the air temperature by between 7.5 and 1.5 °e, depending on the
air mass flow rate. It was furthermore shown in the study that
available theory is able to accurately predict the performance of an
upward facing solar air heater, either with or without water energy
storage, as long as the equations are employed within their range
of validity / AFRIKAANSE OPSOMMING:In die hierdie studie is daar ondersoek ingestel na die
lewensvatbaarhied van son-energiestoring in water ten einde die
tydperk van lugverhitting deur 'n son-Iugverwarmer te verleng. 'n
Sistematiese prasedure is gevolg waardeur daar aanvanklik 'n
aantal eksperimente op 'n son-Iugverwarmer uitgevoer is am
sodoende die eienskappe van so 'n lugverhiUingstelsel, sander
energie storing, te vekry. Die resultate het getoon dat 'n toename
in die massavloei tempo van die lug lei tot 'n toename in die
kollektor effektiwiteit van die stelsel, maar terselfdetyd lei tot 'n
afname in die temperatuur styging in die kollektor. Met die
eienskappe van die lugverwarmingstelsel bekend, is daar voorts 'n
aantal dag- en nag-eksperimente uitgevoer op 'n plastiek bedekte
watertenk am die storing en vryselling van termiese energie deur
die watertenk te kwantifiseer. Die resultate het daarap gedui dat
die plastiek bedekte watertenk nie net beide 'n goeie kollektor en
stoor medium vir son-energie is nie, maar oak dat dit 'n ideale bran
van termiese energie vir 'n lugverwarmingstelsel tydens die nag is.
Met inagname van die vorige resultate, is daar dan 'n aantal
plastiek bedekte watertenks in die apparaat geinstalleer, en 'n
aantal dag- en nag-eksperimente is uitgevoer. Die dageksperimente
het getoon dat die die nuwe lugverwarmer met water
energie storing dieselfde eienskappe toon ten opsigte van die
kollektor effektiwiteit as die oorspronkilke son-Iugverwarmer. Tog,
as gevolg van die laer absoberende plaat temperature was die
temperatuur toename in die kollektor heelwat laer. In kontras
hiermee dui die nagresultate aan dat die plastiek bedekte
watertenks nie net die vermoe het am die tydperk van
lugverwarming te verleng nie, maar oak dat die lug tempertuur,
afhangende van die massavloei tempo van die lug, met tussen 1.5
en 7.5 °C verhoog kan word. Die studie het laastens oak getoon
dat dit moontlik is am met behulp van beskikbare teorie die
temperatuur toename in die kollektor van 'n son-Iugverwarmer met
of sander water energie storing, akkuraat te voorspel, mits die
vergelykings binne hul geldige gebiede gebruik word.
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Lagring av industriell överskottsvärme hos Bharat Forge Kilsta i Karlskoga : Simulering av värmeförluster och regleringsundersökning / Heat storage of industrial excess heat at Bharat Forge Kilsta in Karlskoga : Heat loss simulation and investigation of regulationJohansson, Alexandra January 2016 (has links)
I takt med en ökande befolkning ökar användningen av energi. Samtidigt som energianvändandet ökar, avvecklas kärnkraftverken och därmed ökar kolkraftverkens användning vilket leder till utsläpp av främst koldioxid. Många industrier släpper ut mängder av överskottsvärme i naturen utan att den återanvänds. Ett sätt att ta tillvara på överskottsvärme, som annars går till spillo, är att lagra den. Om värme kan lagras och användas vid en annan tidpunkt kan den ersätta andra energikällor och onödiga utsläpp kan förhindras. Det finns idag tre olika metoder att lagra värmeenergi. Dessa är sensibelt värme, latent värme och kemisk värme. Inom varje metod finns olika system som beskrivs vidare i denna rapport. Bharat Forge Kilsta Kilsta är ett smidesföretag i Karlskoga. Deras smidesugn avger stora mängder värme som dels går till lokaluppvärmning men en del av värmen går till spillo. Skulle överskottsvärmen, som nu går till spillo, kunna lagras på ett effektivt sätt skulle både miljömässiga och kostnadsmässiga besparingar kunna göras. Syftet med rapporten är att redogöra och jämföra olika värmelagringsmetoder i en litteraturstudie för att se vilken typ som passar för industriell överskottsvärme i fallet med Bharat Forge Kilsta. Målet är att översiktligt redovisa olika lagringsmetoder samt olika system inom dessa med avseende på lagringskapacitet och kostnad. Utifrån simulering och reglering av bergrumslager och ackumulatortankar kan en passande metod, med avseende på energidistribution och energieffektivitet samt kostnad, för det specifika fallet väljas. Den mest utvecklade och kommersiellt använda metoden är sensibelt värme, den latenta och kemiska värmelagringen är fortfarande i forskning- och utvecklingsstadiet då de är mer kostsamma. Val av lagringsmetod avgörs utifrån lagringskapacitet, lagringstemperatur, kostnad, geografisk placering samt lagringslängd. Sensibelt värme passar bäst till långtidslagring, vid lägre temperaturer och där lagringskapaciteten måste vara stor till ett lågt pris. Latent och kemisk värme passar bäst för högre temperaturer då värmeförlusterna är små och energidensiteten är hög, kostnaden för dessa är dock hög och de tillämpas enbart i liten skala än så länge. Ur litteraturstudien kunde vissa system uteslutas, de system som skulle passa en industri som Bharat Forge Kilsta var bergrum och ackumulatortank. Resultatet visade att bergrummen har störst värmeförluster jämfört med den totala energin, däremot är lagringskapaciteten större. För att garanterat tillgodose värmebehovet vid extremdagar är det mest lämpligt att använda bergrummen. Kostnadsmässigt är de befintliga tankarna bäst lämpade, däremot klarar de enbart tillgodose värmebehovet i sex timmar vid extrembelastning. Om de befintliga tankarna används som system och 200 m3 tanken tilläggsisoleras kan omkring 100 000 kr per år sparas, räknat med att förlusterna skulle ersätta inköpt fjärrvärme och att skillnaden i värmeförluster enbart sker vinterhalvåret. Återbetalningstiden var kortast för de befintliga takarna, 1,4 år medan en ny ackumulatortank hade längst återbetalningstid, 3,2 år. / When the population increases also the energy use will rise. At the same time the nuclear power plants is decommissioned and the use of coal-fired power plants increases, which leads to large amount of mainly carbon dioxide emissions. Many industries get a lot of excess heat that is released in the nature instead of being reused. One way to reuse excess heat could be to store the heat in a suitable storage for later use. If the excess heat can be stored and be used at a different time it can replace other energy sources and decrease the emissions. Today there is three ways to storage heat, they are sensible heat, latent heat, and chemical heat. In each method there are different systems, these will be described further in this report. Bharat Fore is a large forging company in Karlskoga, Sweden. From their furnace a lot of heat is emitted, some of the heat is used to heat the buildings, but still a lot of excess heat goes to waste. The aim of this report is to compare different heat storage systems and see which one is best suited to industrial excess heat. The goal is to investigate if there is any heat storage method that is effective and cost-saving that fits a larger industry. The purpose of this work is to do a literature study to account and compare different heat storage methods to find the best suitable system for the case with Bharat Forge Kilsta. The goal is to present different storage methods and the different system for each method with respect of cost and storage capacity. From simulation and regulation find the best fitting method for the real case with respect of cost, efficient and storage capacity. The most developed and commercially used method is the sensible heat. Latent heat and chemicals are very costly and still in the research and development stage. Geographic location, using area and operating temperature is parameters that need to be considered when choosing heat storage system. Sensible heat is best suited for long-term storage, at lower temperatures and when the storage capacity needs to be large to a small cost. Latent and chemical heat is best suited for higher temperatures because the heat losses are small and the energy density is high and they are only applied in small scale for now. The result of the literature study showed that storage tanks and cavern storage is most fitting for the case with Bharat Forge Kilsta. The cavern has much larger heat loss compared to the total energy, however the storage capacity is much larger. To guarantee that the heat requirements when there are extreme days it is most appropriate to use the cavern as heat storage. From a coast view it is most fitting to use the already existing tanks, however they could only cater the heat requirement for six hours of heat peak when the production is not running. If the existing tanks is used as heat storage, and the 200 m3 tank will be additional insulated, if the heat loss, in the winter, is replaced with purchased district heating as much as 100 000 SEK per year could be spared. The payback time is shortest for the existing tanks, 1.4 years and almost 3.2 years for the new storage tank.
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Lattice potential energies and theoretical applicationsRoobottom, Helen Kay January 2000 (has links)
No description available.
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High temperature packed bed thermal storage for solar gas turbinesKlein, Peter January 2016 (has links)
A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy, 2016 / Solar powered gas micro-turbines present opportunities for off-grid power generation. Due
to the intermittent nature of the solar energy supply, existing Solar Gas Turbine (SGT) plants
employ hybridisation with fossil fuels to generate dispatchable power. In this work sensible
heat and latent heat storage solutions are investigated as a means of increasing the solar share
of a SGT cycle, thus reducing the consumption of diesel fuel.
The sensible heat storage concept was based on a pressurised packed bed of spherical ceramic
particles, using air as the heat transfer fluid. An axisymmetric, two-phase heat transfer model
of the system was developed, based on the continuous solid phase approach. The model
was successfully validated against experimental data from a packed bed of alumino-silicate
particles over the temperature ranges of gas turbine cycles (350-900 °C and 600-900 °C). The
validated numerical model was utilised to conduct a parametric design study of a six hour
(1.55 MWhth) storage system for a gas micro-turbine. The results show that a high storage
efficiency and high utilisation factor can be achieved when combining sensible heat storage
in alumina with fossil fuel hybridisation, with somewhat lower values without hybridisation.
An analysis of different inventory geometries showed that a packed bed of spherical particles
is best suited to pressurised sensible heat storage.
The latent heat storage concept was based on a pressurised packed bed of Encapsulated
Phase Change Material (EPCM) particles. Sodium sulphate was identified as a suitable phase
change material for the gas turbine cycle. The sensible heat storage model was extended
to account for intra-particle temperature gradients and phase change within the particles.
The intra-particle phase change model was validated against published experimental data
for a single EPCM sphere heated and cooled by convection. The full EPCM storage model
was further successfully validated against experimental data from a packed bed of macro-
encapsulated sodium sulphate particles with alumina shells, up to a temperature of 950 °C.
A comparison of the two storage concepts for a 7 m3 bed shows that a packed bed of en-
capsulated sodium sulphate particles would have a 36% lower energy storage capacity than
a bed of solid alumina particles. This is due to the limited melt fraction in the EPCM bed
when a temperature limit is placed on the base. Increasing the packed bed volume to 10.5 m3
would provide a comparable thermal performance to the 7 m3 solid alumina bed, at a 12%
lower storage mass. A hybrid three-layer packed bed is proposed to increase the volumetric
energy storage density. Modelling shows that this concept could provide a small increase
of 5.3% in the amount of energy discharged above 850 °C, compared to the solid alumina
particles only.
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Etude d’un système de stockage de chaleur thermochimique avec réacteur séparé / Design and analysis of a thermochemical heat storage process with separated reactorFarcot, Lauren 09 March 2018 (has links)
Les systèmes de stockage thermochimique s’avèrent être de bonnes alternatives aux technologies actuelles pour le stockage saisonnier ou intersaisonnier de la chaleur, car l’énergie est stockée sous forme d’un potentiel chimique et donc, il n’y a pas de pertes thermiques pendant la durée de stockage. Un grand nombre d’études a été mené sur le développement de réacteurs thermochimiques intégrés au système de stockage, et peu d’étude ont été menées sur les technologies de réacteur séparé du réservoir de stockage. Ces dernières présentent cependant l’avantage, entre autres, de dissocier la puissance thermique du réacteur et la capacité de stockage de l’installation, ce qui permettrait d’augmenter la densité de stockage.Cette étude se penche sur le développement d’un réacteur thermochimique à lit mobile fonctionnant avec des sels hydratés sous air humide, adapté à des applications aux réseaux de chaleur. Un prototype de réacteur, développé et construit durant cette étude, a permis d’analyser le fonctionnement du réacteur. Cette étude a, entre autres, mis en évidence l’impact des passages préférentiels de l’air sur les performances du réacteur (température et puissance), ainsi que l’importance du titre de vapeur de l’air à l’entrée du réacteur sur ces performances. Il apparaît également que la circulation du solide abaisse sensiblement le point d’équilibre atteint par la réaction.De plus, deux modèles mathématiques ont été développés : un modèle analytique 1D et un modèle 2D prenant en compte les phénomènes de transfert de matière et de chaleur au sein de la zone réactive. Le modèle 2D, validé avec les résultats expérimentaux, a été exploité à l’aide du logiciel de simulation par éléments finis COMSOL Multiphysics afin de mener une étude théorique sur le fonctionnement et les performances du réacteur. Cette étude numérique a porté sur l’influence des conditions opératoires (débit et taux d’humidité de l’air, vitesse du solide) sur les performances et le rendement du système et a permis la comparaison des réacteurs à lit mobile par rapport aux réacteurs à lit fixes, communément développés pour des applications de stockage thermochimique. Cette étude a montré l’importance de la régulation de la vitesse du solide pour l’optimisation des performances du réacteur à lit mobile.L’ensemble de cette étude a permis de mettre en évidence les avantages et les limitations d’un réacteur à lit mobile pour des applications de stockage thermochimique / Thermochemical storage systems prove to be good alternatives to current technologies for seasonal or inter-seasonal storage of heat, because energy is stored as a chemical potential and therefore, there is no heat loss during the storage period. Nowadays, a large number of studies have been conducted on the development of thermochemical reactor integrated in the storage system, andlittle study has been conducted on reactor technologies separated from the storage system. The latter, however, have the advantage, among others, of separating the thermal power produced or consumed and the storage capacity of the installation, which would increase the storage density.This study investigates the development of a moving-bed thermochemical reactor operating with hydrated salts and humid air cross-flow, suitable for district heating applications. A reactor prototype, developed and built during this study, allowed to analyze the functioning of the reactor. This study has, among others, highlighted the impact of the preferential air flow path on the reactorperformances (temperature and power), as well as the importance of the air humidity at the reactor inlet on these performances.In addition, two mathematical models have been developed : a 1D analytical model and a 2D model taking into account the heat and mass transfer phenomena within the reactive area. The 2D model, validated with the experimental results, was exploited using the finite element simulation software COMSOL Multiphysics to conduct a theoretical study on the functioning and the performances of the reactor. This numerical study focused on the influence of operating conditions (air flow rate and moisture content, solid flow rate) on the performances and the efficiency of the system and allowed the comparison of moving bed reactor over fixed bed reactors, commonly developed for thermochemical storage applications. This study has shown the importance of solid velocity control for optimizing the performances of the moving bed reactor.This study has highlighted the advantages and limitations of moving bed reactors for thermochemical storage applications
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