Готові списки джерел за темами / Vapour expansion

Добірка наукової літератури з теми "Vapour expansion"

Автор: Grafiati

Опубліковано: 8 червня 2024

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Статті в журналах з теми "Vapour expansion":

Ahmed, Aram Mohammed, and Attila R. Imre. "The effect of recuperator on the efficiency of ORC and TFC with very dry working fluid." MATEC Web of Conferences 345 (2021): 00012. http://dx.doi.org/10.1051/matecconf/202134500012.

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Organic Rankine Cycles (ORC) and Trilateral Flash Cycles (TFC) are very similar power cycles; ideally, they have a reversible adiabatic (isentropic) compression, an isobaric heating, an isentropic expansion and an isobaric cooling. The main difference is that for ORC, the heating includes the full evaporation of the working fluid (prior expansion); therefore, the expansion starts in a saturated or dry vapour state, while for TFC, the heating terminates upon reaching the saturated liquid states. Therefore, for TFT, expansion liquid/vapour state (in bubbly liquid or in vapour dispersed with droplets), requiring a special two-phase expander. Being ORC a more “complete” cycle, one would expect that its thermodynamic efficiency is always higher than for a TFC, between the same temperatures and using the same working fluids. Surprisingly, it was shown that for very dry working fluids, the efficiency of TFC can exceed the efficiency of basic (i.e. recuperator- and superheater-free) ORC, choosing sufficiently high (but still subcritical) maximal cycle temperature. Therefore in these cases, TFC (having a simpler heat exchange unit for heating) can be a better choice than ORC. The presence of a recuperator can influence the situation; by recovering the proper percentage of the remaining heat (after the expansion), the efficiency of ORC can reach and even pass the efficiency of TFC.

Saini, D. K., A. Baruah, and G. Sachdeva. "Vapour compression system analysis undergoing expansion in an ejector." Journal of Physics: Conference Series 1240 (July 2019): 012131. http://dx.doi.org/10.1088/1742-6596/1240/1/012131.

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Mielczarek, Z. A., and T. J. Trojanowski. "Refrigerant vapour superheat in direct-expansion air cooling coils." International Communications in Heat and Mass Transfer 14, no. 3 (May 1987): 341–46. http://dx.doi.org/10.1016/0735-1933(87)90035-2.

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Miyauchi, Masato, Takumi Watanabe, Daiki Hoshi, and Tomonori Ohba. "Irreversible adsorption of acidic, basic, and water gas molecules on calcium-deficient hydroxyapatite." Dalton Transactions 48, no. 47 (2019): 17507–15. http://dx.doi.org/10.1039/c9dt03704g.

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Guardone, Alberto, Piero Colonna, Emiliano Casati, and Enrico Rinaldi. "Non-classical gas dynamics of vapour mixtures." Journal of Fluid Mechanics 741 (February 13, 2014): 681–701. http://dx.doi.org/10.1017/jfm.2013.13.

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AbstractThe non-classical gas dynamics of binary mixtures of organic fluids in the vapour phase is investigated for the first time. A predictive thermodynamic model is used to compute the relevant mixture properties, including its critical point coordinates and the local value of the fundamental derivative of gas dynamics $\Gamma $. The considered model is the improved Peng–Robinson Stryjek–Vera cubic equation of state, complemented by the Wong–Sandler mixing rules. A finite thermodynamic region is found where the nonlinearity parameter $\Gamma $ is negative and therefore non-classical gas dynamics phenomena are admissible. A non-monotone dependence of $\Gamma $ on the mixture composition is observed in the case of binary mixtures of siloxane and perfluorocarbon fluids, with the minimum value of $\Gamma $ in the mixture being always larger than that of its more complex component. The observed dependence indicates that non-ideal mixing has a strong influence on the gas dynamics behaviour, either classical or non-classical, of the mixture. Numerical experiments of the supersonic expansion of a mixture flow around a sharp corner show the transition from the classical configuration, exhibiting an isentropic rarefaction fan centred at the expansion corner, to non-classical ones, including mixed expansion waves and rarefaction shock waves, if the mixture composition is changed.

Duplat, Jérôme. "Dynamics of expansion and collapse of explosive two-dimensional bubbles." Journal of Fluid Mechanics 859 (November 22, 2018): 677–90. http://dx.doi.org/10.1017/jfm.2018.804.

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An explosive gas mixture of hydrogen and oxygen is introduced in liquid water between two horizontal walls, forming a flat cylindrical bubble. Ignition and explosion of the bubble lead to a large depressurized cavity that finally implodes. We investigate the dynamics of the bubble collapse, which is qualitatively similar to the collapse of a spherical bubble. It exhibits a slightly weaker singularity than for spherical bubbles. We also analyse the explosion process. Starting with an initial radius $R_{0}$, the bubble reaches a maximal radius $R_{max}$ that depends on the gap thickness $h$ between the two walls: for a thinner gap, the condensation of water vapour is more efficient, the overpressure consecutive to the combustion is weaker, and its duration is shorter. This leads to a smaller maximal radius $R_{max}$. An indirect measurement of the transport coefficient of hot water vapour can be inferred from this observation.

Arshed, G. M., S. Z. Shuja, B. S. Yilbas, and M. O. Budair. "Transient Helium Jet Expansion Into Stagnant Air in Relation to Laser Drilling." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 219, no. 7 (July 1, 2005): 667–83. http://dx.doi.org/10.1243/095440605x31517.

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Transient helium jet expansion into a stagnant air environment is modelled to resemble the laser vapour ejection from the cavity during the drilling process. As the metal vapour properties are not known, helium is employed while the previously measured jet inlet velocity profiles are introduced in the simulations. A numerical scheme employing a control volume approach is used to discretize the governing equations of flow. The predictions are validated through a case study associated with an incompressible transient jet flow. It is found that the jet inlet profile influences considerably the self-similar behaviour of the jet. Moreover, the jet expands radially in the early period while as time progresses, the axial penetration of the jet becomes high.

Sarkar, Jahar. "Exergy analysis of vortex tube expansion vapour compression refrigeration system." International Journal of Exergy 13, no. 4 (2013): 431. http://dx.doi.org/10.1504/ijex.2013.058101.

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Liu, Yefeng, and Jun Yu. "Review of vortex tube expansion in vapour compression refrigeration system." IOP Conference Series: Earth and Environmental Science 153 (May 2018): 032021. http://dx.doi.org/10.1088/1755-1315/153/3/032021.

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Gouin, Henri, and Pierre Seppecher. "Temperature profile in a liquid–vapour interface near the critical point." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 473, no. 2204 (August 2017): 20170229. http://dx.doi.org/10.1098/rspa.2017.0229.

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Thanks to an expansion with respect to densities of energy, mass and entropy, we discuss the concept of thermocapillary fluid for inhomogeneous fluids. The non-convex state law valid for homogeneous fluids is modified by adding terms taking account of the gradients of these densities. This seems more realistic than Cahn and Hilliard’s model which uses a density expansion in mass-density gradient only. Indeed, through liquid–vapour interfaces, realistic potentials in molecular theories show that entropy density and temperature do not vary with the mass density as it would do in bulk phases. In this paper, we prove using a rescaling process near the critical point, that liquid–vapour interfaces behave essentially in the same way as in Cahn and Hilliard’s model.

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Дисертації з теми "Vapour expansion":

Poullain, Thomas. "Etude numérique et expérimentale de l’évaporation sous vide d’alliages métalliques : application à la refusion VAR de Zircaloy-4." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0189.

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La maitrise de la composition et de la ségrégation chimique est essentielle lors de l’élaboration de matériaux à forte valeur ajoutée, comme les alliages de zirconium à destination de l’industrie nucléaire. L’élaboration sous vide permet d’obtenir des lingots d’une très grande pureté mais elle présente aussi une contrainte supplémentaire concernant la maitrise de la teneur en éléments d’alliage volatiles. Les travaux présentés dans ce document visent à améliorer la prédiction de la cinétique d’appauvrissement en espèces métalliques volatiles lors de l’élaboration sous vide et en particulier lors de la refusion VAR (Vacuum Arc Remelting ou refusion à l’arc sous vide) du Zircaloy-4, un alliage de Zr. Dans un premier temps, nous étudions la cinétique d’évaporation et l’expansion de la vapeur métallique produite lors de la fusion sous vide. L’étude est effectuée par une combinaison d’expériences en four à bombardement électronique et de la simulation numérique du comportement de la vapeur par une méthode particulaire (FPM). Nos études sur l’évaporation de métaux purs, Ti et Zr, montrent l’importance des collisions au-dessus du liquide sur l’expansion de la vapeur et sa recondensation. La caractérisation de l’expansion de la vapeur de Fe et Sn lors de la fusion sous vide de Zy4, combinée à la simulation particulaire, nous a permis de déterminer la valeur des coefficients d’activité thermodynamique de ces éléments dans le Zy4 liquide. Dans un second temps, nous présentons la simulation de l’expansion de la vapeur métallique dans les conditions du procédé VAR en nous intéressant particulièrement aux flux de condensation sur les différentes surfaces. L’application de ce modèle au Zircaloy-4 montre que la composition du dépôt sur la paroi interne de la lingotière est très différente de celle de l’alliage. Enfin, le modèle particulaire est couplé à une modélisation de la croissance du lingot et nous étudions l’influence de l’évaporation, condensation et réincorporation de la collerette sur la composition et la ségrégation des éléments d’alliage volatils. Le couplage offre aussi une première prédiction de l’épaisseur et de la composition de la collerette que nous comparons pour la refusion du Zyrcalloy-4 avec des prélèvements industriels
Composition and chemical segregation control is primordial when producing high value-added materials, such as zirconium alloys for nuclear industry. Vacuum processing allows production very high purity ingot, however it also presents an additional problematic concerning control and prediction of alloy elements evaporation. This PhD dissertation aims at improving prediction of volatile metallic species evaporation during vacuum elaboration, especially during Zircaloy 4 VAR (Vacuum Arc Remelting).First, the evaporation kinetics and the expansion of the metal vapour produced during vacuum melting is investigated. The study is done with a combination of volatilisation experiments using an experimental electron beam furnace and particle based numerical simulation (FPM) of vapour behaviour. Our volatilisation studies on pure metals, Ti and Zr, show the importance of collisions above the liquid on the vapour expansion and its recondensation. Determination of Fe and Sn vapour expansion during Zy4 vacuum melting combined with particle simulation, allowed us to determine thermodynamic activity coefficients values for these elements in liquid Zy4.Then, metallic vapour expansion under VAR conditions is studied, with particular interest shown to condensation flows on the different surfaces. Application of our numerical model to Zy4 shows that the vapour deposited on the mould has a very different composition compared to the alloy. Finally, the particle model is coupled to an ingot growth model and we study the influence of evaporation, condensation and crown reincorporation with regard to volatile solute segregation and depletion. This coupling also provides a first prediction of crown thickness and composition and we compare them to industrial crown samples

Semeraro, Emanuele. "Experimental investigation on hydrodynamic phenomena associated with a sudden gas expansion in a narrow channel." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066516/document.

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La vaporisation rapide du sodium liquide surchauffé est supposée être à l’origine des arrêts automatiques pour réactivité négative du réacteur Phénix.Un dispositif expérimental a été mis en œuvre pour reproduire la détente d'un gaz pressurisé, repoussant un liquide dans un canal de section rectangulaire très allongée.L’interface qui sépare les deux fluides, initialement plate, ondule du fait d'instabilités de Rayleigh-Taylor dont le caractère 2D est garanti par le rapport d'aspect de la section du canal. L’aire interfaciale augmente d'un facteur 50.L’expansion du gaz peut être divisée en deux phases principales : une phase dite « de Rayleigh-Taylor » (linéaire et non-linéaire) et une phase dite « à multi-structures » (transitionnelle et chaotique). La première est caractérisée par la dynamique de l'interface et l’aire interfaciale qui en résulte est proportionnelle à l’amplitude des ondulations. La deuxième est influencée par le comportement des structures liquides, dispersées dans la matrice gazeuse et l’aire interfaciale est alors proportionnelle au nombre de structures.La distribution de fraction volumique suggère un modèle d’écoulement composé de trois régions : une région où la frontière des bulles est clairement définie et régulière, une région compartimentée par des membranes liquides issues des frontières des bulles, une région diphasique formée de la queue de ces structures. L’analyse de sensibilité à la tension superficielle confirme que plus la tension est faible, plus les interfaces sont instables. Les ondes sont plus prononcées et plus de structures sont produites, ce qui conduit à une majoration du taux de production de l’aire interfaciale
The sharp vaporization of superheated liquid sodium is investigated. It is suspected to be at the origin of the automatic shutdown for negative reactivity, occurred in the Phénix reactor at the end of the eighties.An experimental apparatus has been designed and operated to reproduce the expansion of overpressurized air, superposed to water in a narrow vertical rectangular section channel.When expansion begins, the initial flat interface separating the two fluids becomes corrugated under the development of two-dimensional Rayleigh-Taylor instabilities. The interface area increases significantly and becomes even 50 times larger than the initial value. Since the channel is very narrow, instabilities along the channel depth do not develop.The gas expansion in a narrow channel can be divided into two main phases: Rayleigh-Taylor (linear and non-linear) and multi-structures (transition and chaotic) phases. The former is characterized by the dynamic of corrugated profile and the interface area results proportional to the amplitude of corrugation The latter is influenced by the behavior of the liquid structures dispersed in gas matrix and the interface area is mainly proportional to the number of liquid structures.The distribution of volume fraction suggests a model of channel flow consisting of three regions: the regular profile of peaks, the spike region and the structures tails. The analysis of sensibility to surface tension confirms that, with a lower surface tension, the fluids configuration is more unstable. The interface corrugations are more pronounced and more structures are produced, leading to a higher increment of the interface area

Hwang, Moonkyu. "Numerical modeling of the expansion phase of vapor explosions." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/16761.

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Souza, Rafaela Faciola Coelho de. "Estudo da influência da sucção na pressão de expansão de materiais argilosos com a técnica da transferência de vapor." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18132/tde-19102015-105616/.

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Este trabalho apresenta a quantificação da expansão e suas características, principalmente a influência da sucção, em amostras de materiais sedimentares argilosos provenientes da Formação Corumbataí, aflorantes no interior do estado de São Paulo. Foram testadas amostras indeformadas, e amostras destorroadas e compactadas em diferentes umidades, em ensaios de pressão de expansão a volume constante por inundação, e também, com sucção controlada por meio da técnica da transferência de vapor. Foram ensaiadas, ainda, misturas compactadas desse material com bentonita em diferentes proporções, e misturas de bentonita com material não expansivo arenoso oriundo da Formação Botucatu. O controle de sucção foi realizado pelo uso de soluções salinas de NaCl em concentrações preparadas para impor sucções de 40.000, 25.000, 10.000 e 5.000 kPa. Para a realização dos ensaios, construiu-se um sistema de aplicação de cargas e de aquisição automática dos dados de pressão. Para acelerar o processo de umedecimento por vapor, utilizou-se um reservatório externo ligado em uma bomba de ar adaptada para promover a circulação do vapor de ar para dentro da célula edométrica, especialmente construída para esta pesquisa. Os resultados de expansão nos ensaios com inundação mostraram pressões de expansão crescentes com a diminuição dos teores de umidade, e consequente aumento da sucção inicial das amostras ensaiadas, bem como crescentes com o aumento na proporção de bentonita nas misturas, com valores máximos em torno de 700 kPa para o ensaio com a bentonita pura compactada seca. A análise da microestrutura das amostras por meio da porosimetria por intrusão de mercúrio permitiu constatar que as amostras indeformadas apresentaram variação, apenas, nos macroporos após a expansão; e as compactadas na umidade ótima e, posteriormente secas ao ar, não mostraram evolução significativa após a expansão. Na microscopia eletrônica de varredura (MEV) foi possível verificar a mudança nos vazios das amostras, bem como, visualizar a variação na estrutura e na textura. Além disso, no MEV foram confirmados, também, os argilominerais determinados na caracterização mineralógica. Os resultados dos ensaios de expansão com sucção controlada mostraram ausência de pressão de expansão para as amostras da Formação Corumbataí nas condições indeformada, e na condição compactada na umidade ótima e posteriormente seca ao ar. No entanto, esse material, quando compactado seco na forma de pó, e também, compactado seco misturado com bentonita em diferentes proporções, revelou pressões de expansão com a transferência de vapor, assim como, as misturas de bentonita com material não expansivo da Formação Botucatu. A ausência de expansão foi justificada pela forma lenta de umedecimento proporcionada pela transferência de vapor que, apesar de promover o aumento do teor de umidade das amostras, não mobilizou variação volumétrica suficientemente capaz de transmitir como pressão de expansão. Portanto, os ensaios de expansão, com a utilização da técnica de transferência de vapor, foram efetivos para avaliar a expansão somente nos casos em que argilominerais com potencial expansivo estavam presentes em proporções consideráveis.
This thesis presents the quantification and characterization of expansion, especially the influence of suction on samples of sedimentary materials from Corumbatai Formation that occurs in Sao Paulo. Undisturbed and compacted samples with different moisture contents were tested with swelling pressure tests at constant volume method by flooding, and also with suction control by vapour transfer technique. Compacted mixtures of this material with bentonite in differents proportions, and mixtures of bentonite with sandy non-expansive material from the Botucatu Formation were also tested. The suction control was performed by the use of NaCl salt solutions at concentrations prepared to perform 40,000, 25,000, 10,000 and 5,000 kPa suctions. For the tests, it was developed a system for load application and automatic retrieval of pressure. To accelerate the wetting process by vapour, we used an external reservoir connected to an air pump adapted to promote air circulation inside the edometric cell, specially made for this study. The expansion results in flooding tests showed increasing swelling pressure with decreasing moisture content. Consequently there was an increase in the initial suction of the tested samples, which kept increasing as the rate of bentonite was raised in the mixtures, with a peak of ca. 700 kPa for the test with dry pure bentonite compacted. In the microstructure analysis of the samples by mercury intrusion porosimetry, the samples showed variation only in macropores after swell; and the ones compacted at optimum moisture, and subsequently air dried, showed no significant change after the swell. In scanning electron microscopy (SEM) it was possible to verify the change in the voids of the samples, as well as to visualize the variation in the structure and texture. In addition, the SEM confirmed clay minerals deterninated in mineralogical characterization. The results of controlled suction with swell tests showed absence of swell pressure for Corumbatai samples tested in undisturbed conditions, and compacted condition at optimum moisture content, and then air dried. However, when compacted in the form of dry powder, as well as when compacted dry, mixed with different proportions of bentonite, this material showed swelling pressures with vapor transfer technique, as well as mixtures of bentonite with non-expansive material of Botucatu Formation. The absence of swell was explained by the slow damping provided by the vapor transfer that although promoting increasing dampen, did not sufficiently mobilized volume variation capable of transmitting blowing pressure. Therefore, the swell tests with the vapor transfer technique were effective to evaluate the swelling just in cases where clay minerals with swell potential were present in significant proportions.

Akraiam, Atea I. Bubaker. "Metal cluster production by condensation of metal vapour in supersonic expansions and by aggregation in droplets." Thesis, University of Leicester, 2015. http://hdl.handle.net/2381/31834.

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Metal clusters have been produced by condensation of metal atoms on or inside small argon clusters and by collision of supersonic atomic argon beams with atomic metal vapours. A key parameter in both processes is the metal atom particle density. For iron, metal particle densities above a thermal open crucible-type evaporator were determined using quartz-micro-balance mass flux measurements, revealing a point-source-like dependence on the distance from the crucible. For silver atoms the particle densities were also determined using scattering from small argon clusters. Formation and soft-deposition of iron nanoparticles was first attempted using a supersonic beam of argon atoms that was blown into a vapour of iron atoms. Transmission electron microscopy showed the presence of iron nanoparticles whose size depended on the deposition time, showing that aggregation takes place after deposition. The deposition rates were of the order of 0.01 nm/s. In the second part of the study argon clusters containing on average 21 atoms were directed through vapours of xenon or silver atoms. Time-of-flight mass spectrometry showed the presence of xenon and silver clusters when the xenon or silver particle densities were increased. The xenon clusters contained up to four atoms whereas silver would only formdimers. The mass spectra also showed argon atoms attached to the xenon clusters, but not to the silver dimers, which was attributed to the high temperature of the silver dimers.

Suardin, Jaffee Arizon. "The application of expansion foam on liquefied natural gas (LNG) to suppress LNG vapor and LNG pool fire thermal radiation." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2906.

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SILVEIRA, HELVECIO C. K. da. "Analise de integridade estrutural de tubos de geradores de vapor deteriorados por corrosao sob tensao pelo primario na regiao de transicao de expansao junto ao espelho." reponame:Repositório Institucional do IPEN, 2002. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11035.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Patiño, Pérez Jorge. "Experimentación de nuevas configuraciones destinadas a la mejora del COP en ciclos de compresión de vapor que utilizan CO2 como refrigerante." Doctoral thesis, Universitat Jaume I, 2013. http://hdl.handle.net/10803/125529.

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La creciente demanda del confort humano está obligando a la comunidad científica a buscar nuevas técnicas que permitan aprovechar al máximo los recursos disponibles. Gran parte de esta demanda es consumida por sistemas de producción de frío basados en la compresión de vapor, por tanto, constituye uno de los sectores estratégicos a tener en cuenta para contribuir al desarrollo sostenible mediante la optimización energética de las instalaciones frigoríficas. Además de la búsqueda de soluciones eficientes desde un punto de vista energético, la comunidad científica dirige sus esfuerzos en la búsqueda de nuevas sustancias refrigerantes cuyo efecto no sea nocivo para el medio ambiente.

Con el fin de contribuir y fomentar el uso del fluido natural CO2 como refrigerante, se ha elaborado la presente tesis doctoral que está centrada en estudios teóricos y posterior análisis experimental del funcionamiento de una planta frigorífica de compresión de vapor que emplea CO2 como refrigerante en condiciones supercríticas. Esta nueva iniciativa permite minimizar al máximo el impacto medioambiental generado por las emisiones de refrigerantes artificiales, aunque requiere de una tecnología completamente nueva debido a las propiedades físicas del propio refrigerante. El objeto de este análisis se centra en continuar buscando aquellas configuraciones que logren mejorar el rendimiento energético de las instalaciones que empleen R744 como refrigerante.

En la presente tesis doctoral se ha efectuado un estudio experimental de una configuración con un sistema de expansión en una única etapa, donde se ha analizado la influencia del aceite en la masa de refrigerante a cargar en la instalación y en el comportamiento de la misma. Este funcionamiento se compara con el comportamiento que adopta un ciclo que cuenta con un sistema de doble etapa de expansión y depósito intermedio entre ambas etapas, que le proporciona la masa que necesita en todo momento. Además, se estudia el comportamiento de la instalación al insertar en ambas configuraciones un IHX. Por otro lado, en este trabajo también se ha llevado a cabo un análisis experimental de la instalación operando en régimen supercrítico frente al modo de operación en régimen subcrítico cuando las condiciones externas lo permiten. De esta forma, se evalúa la posibilidad de operar con ambos sistemas a partir de una instalación dimensionada para operar en régimen supercrítico. El último análisis experimental realizado se basa en la búsqueda de nuevas configuraciones para mejorar el rendimiento energético del equipo, donde se estudia la extracción de vapor en el depósito de acumulación y la posterior inyección ó recompresión en diferentes puntos de la instalación.

Estos análisis experimentales se han complementado con estudios de carácter teórico. El primer estudio teórico se ha basado en el modelado de la instalación frigorífica para analizar la energía calorífica generada en el foco caliente y destinada a activar otras aplicaciones. El segundo estudio ha consistido en el modelado matemático de dos tipos diferentes de intercambiadores de calor, uno de tubo concéntrico y flujo paralelo y otro de flujo cruzado con tubos aleteados externamente.

Gana, Inès. "Caractérisation physique et chimique des substances à activité thérapeutique : application aux études de profil de stabilité et de préformulation." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015USPCB164/document.

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Le développement d’un médicament pour une cible thérapeutique donnée passe par plusieurs étapes qui se résument en une étape de criblage, une phase préclinique et plusieurs phases cliniques. Ces étapes permettent de sélectionner une substance active et de démontrer son efficacité thérapeutique et sa sécurité toxicologique. Ces deux critères définissent la qualité du médicament qui, une fois démontrée, doit être garantie pendant toute sa durée de validité. La qualité est évaluée au moyen d’études de stabilité qui sont réalisées d’abord sur la matière première de la substance active au cours de la phase de pré-développement du médicament, ensuite sur le produit fini. La stabilité intrinsèque de la substance active concerne à la fois ses propriétés chimiques et ses propriétés physiques qui sont liées à la nature de la substance. L’étude de stabilité repose d’abord sur la caractérisation de ces propriétés, et ensuite sur l’étude de la sensibilité de la substance à l’égard des facteurs environnementaux pouvant modifier les propriétés intrinsèques de la substance. L’approche adoptée dans ce travail repose d’une part sur l’évaluation de la stabilité chimique c’est à dire de la réactivité chimique des substances à usage pharmaceutique au travers des études de pureté chimique et des études de dégradation forcée de ces substances en solution, et d’autre part, sur l’évaluation de la stabilité physique. Dans ce cadre, l’étude du polymorphisme cristallin revêt une grande importance, tout comme l’aptitude à la formation d’hydrates ou de solvates. Cette étude, basée sur la thermodynamique, consiste pour l’essentiel à construire un diagramme de phases pression-température permettant de définir les domaines de stabilité relative des différentes formes cristallines. Cinq substances actives, existant à l’état solide et entrant dans la composition de médicaments administrés par voie orale, ont été étudiées dans le cadre de ce travail. L’analyse chimique du tienoxolol, présentant un effet anti-hypertenseur, a montré qu’il est très sensible à l’hydrolyse et à l’oxydation. Sept produits de dégradation ont été identifiés pour ce produit dont un schéma probable de fragmentation a été établi. Des diagrammes de phases pression-température ont été construits pour le bicalutamide et le finastéride, médicaments du cancer de prostate, en utilisant une approche topologique basée simplement sur les données disponibles dans la littérature. Cette étude a montré que la relation thermodynamique (énantiotropie ou monotropie) entre les formes cristallines sous conditions ordinaires peut être modifiée en fonction de la température et de la pression. Ce résultat est important pour la production des médicaments car il montre comment une telle information peut être obtenue par des mesures simples et accessibles aux laboratoires de recherche industrielle, sans que ces derniers soient contraints d’expérimenter sous pression. La méthode topologique de construction de diagramme de phases a été validée ensuite en la comparant à une méthode expérimentale consistant à suivre, par analyse thermique, des transitions de phases en fonction de la pression. La méthode expérimentale a été appliquée à deux composés, la benzocaine, anesthésique local, et le chlorhydrate de cystéamine, médicament utilisé pour les cystinoses. Les deux formes étudiées de benzocaine présentent une relation énantiotrope qui se transforme en relation monotrope à haute pression. Une nouvelle forme cristalline (forme III) du chlorhydrate de cystéamine a été découverte au cours de ce travail. La relation thermodynamique entre cette forme III et la forme I est énantiotrope dans tout le domaine de température et de pression. De plus, le chlorhydrate de cystéamine, classé hygroscopique, a fait l’objet d’une étude quantitative de sa sensibilité à l’eau, montrant qu’il devient déliquescent sans formation préalable d’hydrate (...)
The development of a drug for a given therapeutic target requires several steps, which can be summarized by drug screening, a preclinical phase and a number of clinical phases. These steps allow the selection of an active substance and a verification of its therapeutic efficacy and toxicological safety. The latter two criteria define the quality of the drug, which once demonstrated, must be guaranteed throughout its shelf life. Quality is assessed through stability studies that are carried out with the raw material of the active substance (preformulation phase) and with the final product. The intrinsic stability of the active substance depends on its chemical and physical properties and their characterization is the core of the stability studies, which in addition consists of sensitivity studies of the active pharmaceutical ingredient (API) for environmental factors that can modify the intrinsic properties of the substance. The approach presented in this work is based on the one hand on the assessment of the chemical stability, i.e. the reactivity of APIs through chemical purity studies and forced degradation in solution, and on the other hand on the assessment of the physical stability. For the latter, crystalline polymorphism is of great importance, as is the ability of the API to form hydrates or solvates. The study of crystalline polymorphism is based on the construction of pressure-temperature phase diagrams in accordance with thermodynamic requirements leading to the stability condition domains of the different crystalline forms. The stability behavior of five APIs used or meant for oral applications has been studied as part of this work. The chemical analysis of tienoxolol, an antihypertensive drug, has demonstrated its sensitivity for hydrolysis and oxidation. Seven degradation products were identified and patterns of fragmentation have been established. Pressure-temperature phase diagrams have been constructed for bicalutamide and finasteride, drugs against prostate cancer, using a topological approach based on data available in the literature. The study demonstrates that the thermodynamic relationship (enantiotropy or monotropy) between crystalline forms under ordinary conditions can change depending on the pressure. This is important for drug development as it demonstrates how stability information can be obtained by standard laboratory measurements accessible to industrial research laboratories without the necessity to carry out experiments under pressure. The topological approach for the construction of phase diagrams has subsequently been validated by measuring transition temperatures as a function of pressure. Experiments have been carried out with benzocaine, a local anesthetic, and with cysteamine hydrochloride, a drug used against cystinosis. Two crystalline forms were observed in the case of benzocaine. They exhibit an enantiotropic relationship that becomes monotropic at high pressure. For cysteamine hydrochloride, a new crystalline form (form III) was discovered. The thermodynamic relationship between the new form III and the known form I is enantiotropic for the entire temperature and pressure range. Cysteamine hydrochloride’s sensitivity to water has been studied, as it is hygroscopic. It has been demonstrated that it becomes deliquescent in the presence of water and no trace of a hydrate has been found. Finally, a study combining thermal and chromatographic methods showed that, under the effect of temperature, cysteamine hydrochloride turns into cystamine in the solid as well as in the liquid state, The latter is known to be an important impurity of cysteamine hydrochloride. In conclusion, the approach developed in this work allowed to characterize the stability properties of a number of APIs and to determine the factors that may change these properties and influence the intrinsic stability (...)

Glos, Jan. "Modelování a řízení toků elektrické a tepelné energie v plně elektrických automobilech." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-433039.

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Systematické řízení tepelných a elektrických toků v plně elektrických automobilech se stává velmi důležitým, protože v těchto typech automobilů není k dispozici dostatek odpadního tepla pro vytápění kabiny. Aby v zimním období nedocházelo ke snížení dojezdu, je nutné použití technologií, které umožní snížení spotřeby energie nutné k vytápění kabiny (např. tepelné čerpadlo, zásobník tepla). Je také zapotřebí vytvořit řídicí algoritmy pro tato zařízení, aby byl zajištěn jejich optimální provoz. V letním období je nezbytné řídit tepelné toky v rámci elektromobilu tak, aby nedocházelo k nadměrnému vybíjení baterie kvůli chlazení kabiny a dalších částí. Tato práce řeší jak návrh řídicích algoritmů, tak i vývoj rozhodovacího algoritmu, který zajistí směřování tepelných toků.

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Книги з теми "Vapour expansion":

American Society of Mechanical Engineers., ed. Cylinder proportions for the compound engines determined by their free expansion losses. [S.l: s.n., 1986.

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Center, Langley Research, ed. Chemical vapor deposition fluid flow simulation modelling tool. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1992.

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Buchetti, Jacques. Machines a Vapeur Actuelles, Supplément, Machines Simples: Compound a Triple Expansion ... Creative Media Partners, LLC, 2018.

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Частини книг з теми "Vapour expansion":

Das, K. S., and S. K. Wilson. "The Unsteady Expansion and Contraction of a Two-Dimensional Vapour Bubble Confined Between Superheated or Subcooled Plates." In Progress in Industrial Mathematics at ECMI 2004, 489–93. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/3-540-28073-1_72.

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Zauner, E., and G. E. A. Meier. "Phase Changes of a Large-Heat-Capacity Fluid in Transcritical Expansion Flows." In Adiabatic Waves in Liquid-Vapor Systems, 103–12. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-83587-2_10.

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Peters, F., and B. Paikert. "Growth of n-Propanol Droplets in Argon Studied by Means of Shock Tube Expansion-Compression Process." In Adiabatic Waves in Liquid-Vapor Systems, 217–26. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-83587-2_19.

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Gspann, J. "Large clusters of cesium from pure vapor expansions." In Small Particles and Inorganic Clusters, 871–73. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76178-2_210.

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Vostrikov, A. A., and D. Yu Dubov. "Cluster generation in expansions of pure water vapour and of mixtures with carbon dioxide." In Small Particles and Inorganic Clusters, 879–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76178-2_212.

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Pisano, Antonio. "Physics in a Vaporizer: Saturated Vapor Pressure, Heat of Vaporization, and Thermal Expansion." In Physics for Anesthesiologists, 105–13. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-57330-4_12.

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Pruett, J. G., H. Windischmann, M. L. Nicholas, and P. S. Lampard. "Mass and Temperature Measurement in Pure Vapor Expansion of Metals and Semi-Metals." In Physics and Chemistry of Small Clusters, 109–14. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4757-0357-3_17.

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Pisano, Antonio. "Physics in a Vaporizer: Saturated Vapor Pressure, Heat of Vaporization, and Thermal Expansion." In Physics for Anesthesiologists and Intensivists, 173–84. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-72047-6_15.

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"- The formation of disperse systems by homogeneous condensation with vapour jet expansion." In Processes of Formation of Micro -and Nanodispersed Systems, 143–91. CRC Press, 2015. http://dx.doi.org/10.1201/b19771-6.

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Zinn-Justin, Jean. "Critical exponents and equation of state from series summation." In Quantum Field Theory and Critical Phenomena, 975–91. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198834625.003.0041.

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Universal quantities near the phase transition of O(N) symmetric vector models, can be determined, in the framework of the (f² )² field theory, and the corresponding renormalization group (RG), in the form of perturbative series. The O(N) symmetric field theories describe, in particular for N = 0, the universal properties of the statistics of long polymers, for N = 1, the liquid–vapour transition, for N = 2, superfluid helium transition, and so on. Universal quantities have been calculated within two different schemes, the Wilson-Fisher ϵ = 4 − d expansion, and perturbative expansion at fixed dimensions 2 and 3 (as suggested by Parisi). In both cases, the series are divergent, and the expansion parameters are not small. In fixed dimensions smaller than 4, the series are proven to be Borel summable. For the ϵ expansion, there are reasons that the property is equally true, but a proof is lacking. With this assumption, in both cases, although the series are divergent, they define unique functions. Since the expansion parameters are not small, summation methods are then required to determine these functions. A specific summation method, based on a parametric Borel transformation and mapping, in which the knowledge of the large order behaviour has been incorporated, has been successfully applied to the series, and has led to a precise evaluation of critical exponents and other universal quantities.

Тези доповідей конференцій з теми "Vapour expansion":

Bergero, Stefano, Anna Chiari, and Enrico Nannei. "Vapour Compression and Liquid Desiccant Hybrid System for Air Conditioning." In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95541.

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The present study examines the performance of a hybrid air-conditioning system in which a vapour compression inverse cycle is integrated with an air dehumidification system working with hygroscopic solution and hydrophobic membrane. This approach may prove to be a valid alternative to the traditional summertime air-conditioning system, which involves cooling the air to below its dew point and subsequently reheating it. The system examined simultaneously cools and dehumidifies the air in an air-LiCl solution membrane vapour exchanger before it enters the conditioned environment. The LiCl solution is cooled by means of a vapour compression inverse cycle that uses the refrigerant KLEA 407C. The heat rejected by the condenser is used to regenerate the solution. A SIMULINK calculation programme was used to simulate the system in steady-state conditions. The performance of the system was analysed on varying significant operating parameters and was compared with that of a traditional direct-expansion air-conditioning plant. The results of the simulations revealed significant power saving which, in certain operating conditions, was as much as 50%.

Stosic, Nikola, and Ian K. Smith. "Utilization of Expansion Work in Transcritical CO2 Heat Pumps in Combined Heating and Cooling." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68722.

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The use of CO2 as a refrigerant in transcritical vapour compression cycles has significant advantages, for systems which require simultaneous heating and cooling at approximately equal rates. However, then need for a compressor, to operate across high pressure differences, and the large throttle losses associated with these pressure differences have limited its use. This paper describes a study carried out to evaluate the efficiency gains and cost benefits possible from such a system when a twin screw machine is used to both compress and expand the working fluid in a single unit. It also shows the values of the critical design parameters required to optimise the system’s potential advantages when used in larger combined heating and cooling systems in industrial process and heat generation plants. The results show that recovery of work from the expansion process improves the COP by 15 to 20%. For the design conditions specified in this paper, this implies that the expander is worth fitting if it can be installed for a cost of less than approximately €750/kW of shaft power input. Thus, depending on the operating conditions, transcritical CO2 heat pumps using a compressor-expander can produce hot water at 90°C with a COP of approximately 6, with thermal outputs of up to 1.5 MW. This could be extended with simple control strategies up to outputs of 10 MW.

Read, Matthew G., Ian K. Smith, and Nikola Stosic. "Optimisation of Power Plant Operating on Waste Heat of Gas IC Engine Driven Power Generator." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-66550.

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This paper describes the results of computation analysis aimed at assessing the potential benefits of several thermodynamic cycles for the recovery of waste heat from gas IC engines. This is achieved by modelling the plant and expander processes which provides the general specification of the plant in terms of key design parameters. Simultaneously, the thermodynamic performance of each cycle is calculated in terms of flow rate, power and efficiency. Detailed component models allow a rigorous investigation of the design and performance of Organic Rankine Cycle and Wet steam Cycle systems for these applications where the energy from both the water jacket and exhaust gas can be utilised. A number of system configurations are considered including cycles with wet steam expansion and organic Rankine cycles with dry vapour expansion, and the benefits of a steam-ORC cascaded arrangement are investigated. Optimisation of the system configurations provides valuable insight into the performance and practical requirements of IC waste heat recovery systems.

Parsons-Karavassilis, D., K. Dowling, P. M. W. French, and J. R. Taylor. "Laser ablation using an ultrafast all-solid-state Cr:LiSAF regenerative laser amplifier system." In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1998. http://dx.doi.org/10.1364/cleo_europe.1998.cthh76.

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Conventional continuous wave and long pulse (nanosecond) laser ablation is used in many fields, such as materials processing and medicine [1]. In these regimes the dominant process involved is the heating of the target material through the liquid phase to the vapour phase, resulting in expansion and expulsion of the desired target material. This is accompanied by heating and collateral damage to the surrounding area, the degree of which is determined by the rate of energy absorption and the rate of energy loss through thermal conduction in the material. This collateral damage is often detrimental and a limiting factor when high precision ablation is required.

Spinelli, A., V. Dossena, P. Gaetani, C. Osnaghi, and D. Colombo. "Design of a Test Rig for Organic Vapours." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22959.

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A blow-down wind tunnel for real gas applications has been designed to characterize an organic vapour stream by independent measurements of pressure, temperature and velocity. Experiments are meant to investigate flow fields representative of expansions taking place in Organic Rankine Cycles (ORC) turbines. Strong real gas effects, high Mach numbers and approximations affecting the calculated properties of novel compounds, make the knowledge of ORC turbine blade passage flow field still rather limited. A significant enhancement of turbines efficiency is expected from detailed investigations on expansion streams. Despite Organic Cycles have attracted large research efforts in recent years, present days design tools still suffer from a lack of relevant experimental data. So far, ideal gas test cases and equilibrium measurements have supported separately CFD and thermodynamic model validations. These considerations prove the relevance of such a test rig. This paper discusses the design and the final layout of the facility, whose construction is currently in progress. A straight axis supersonic nozzle has been chosen as test section for early tests; investigations on blade cascades are foreseen in the future. Due to high stream densities and temperatures, a throat size compatible with probes intrusion made a continuous cycle plant unaffordable, requiring an input thermal power of around 2.5 MW. A reduction to 30 kW has been achieved by adopting a blow-down tunnel: the fluid, slowly vaporized in a high pressure vessel, feeds the nozzle at a lower pressure. The vapour is then collected in a low pressure tank and condensed. The loop is closed by liquid compression through a pump. Such a batch operating system also offers the option to select test/condensation pressures and temperatures, allowing experimentation of a wide variety of working fluids, even though new ORC compounds (e.g. Siloxanes, Fluorocarbons) remain of major interest. Maximum temperature and pressure are 400 °C and 50 bar. Despite the unsteady operational mode, the inlet nozzle pressure can be kept constant by a control valve. Depending on the fluid and test pressure, experiments may last from 20 seconds to several minutes, while their set-up requires a few hours. Fast response pressure transducers, pressure probes and thermocouples have been selected for thermodynamic measurements; Laser Doppler Velocimetry (LDV) and Schlieren techniques allow direct measurements of velocity and flow visualization. The design has been carried out with a lumped parameter approach, using Siloxane MDM and Hydrofluorocarbon R245fa as reference compounds and FluidProp® for properties calculation.

Zanforlin, S., and R. Gentili. "Stable Fuel Confinement in Stratified Charge GDI Engines." In ASME 2004 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/icef2004-0919.

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Direct fuel injection combined with charge stratification represents a must for two-stroke S.I. engines, since it prevents fuel loss from the exhaust port and incomplete combustion or misfire at light loads. The most difficult aims are keeping stable stratification when engine operating conditions change and, at very light loads, avoiding excessive dilution and spreading of fuel vapour in consequence of burned gas expansion. Two new-concept engine designs are proposed in this paper. In both cases shapes of piston and head, together with scavenging-duct orientation have been optimised to obtain stable in-cylinder flow field features (independently of engine speed) and proper fuel distribution at ignition time. Computational Fluid Dynamics (CFD) predictions at different loads and speeds are reported and discussed.

Bergero, Stefano, and Anna Chiari. "Energy Saving in a Heat Pump Air-Conditioning System Using Liquid Desiccant and Membrane Contactors." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-63516.

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It has been demonstrated in the literature that significant energy savings can be achieved in air-conditioning through the use of so-called hybrid systems, in which a chemical dehumidification system is combined with a vapour-compression heat pump. The advantage of such systems lies in the fact that the heat pump can operate at a higher evaporation temperature than that of a traditional system in which dehumidification is achieved through condensation, thereby achieving higher coefficients of performance. The hybrid system described in the present paper operates as follows: the air supplied to the conditioned ambient is simultaneously cooled and dehumidified in an air-solution membrane contactor. The LiCl solution is cooled by means of a vapour-compression heat pump using the refrigerant KLEA 410A. The solution is regenerated in another membrane contactor by exploiting the exhaust air and the heat rejected by the condenser. A study of the steady-state behaviour of the system in summer climatic conditions was carried out, on varying some significant operating parameters, such as the thermal efficiency of the heat exchangers, the outdoor temperature and the sensible load of the conditioned room. The performances of the hybrid system were compared with those of a traditional direct-expansion air-conditioning plant; the results of the simulations reveal that, in particular operating conditions, energy saving can exceed 50%.

Roumeliotis, I., and K. Mathioudakis. "Moisture Condensation Effect on Turbine Performance Tests." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53839.

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Water is always present in the atmospheric air in the form of vapour, affecting the operation of turbomachinery components in gas turbine engines. Due to water presence in the working medium, condensation may occur, which can influence the thermal performance of the component and alter the measurements taken for calculations. This can lead to erroneous evaluation of component performance parameters during development performance tests. Procedures to detect condensation and if possible to correct the measurements during engine or component test should be used to avoid such situations. A method allowing the prediction of condensation and the correction of the measurements for low speed expansion is presented. The method is implemented in turbine testing measurements where condensation occurs and the results show that condensation may be predicted and its effects corrected.

Tang, Z., H. Kim, I. Yaroslavski, G. Masindo, Z. Celler, and D. Ellsworth. "Novel Thermal Barrier Coatings Produced by Axial Suspension Plasma Spray." In ITSC2011, edited by B. R. Marple, A. Agarwal, M. M. Hyland, Y. C. Lau, C. J. Li, R. S. Lima, and A. McDonald. DVS Media GmbH, 2011. http://dx.doi.org/10.31399/asm.cp.itsc2011p0571.

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Abstract Ceramic Thermal Barrier Coatings (TBCs) on superalloy components are being used successfully in land-based gas turbine and aircraft engines. These coatings are generally made by either air plasma spraying (APS) or electron beam physical vapour deposition (EB-PVD). In general, EB-PVD TBCs have superior durability due to the columnar structure, but they are very expensive compared to APS TBCs. EB-PVD TBCs are used primarily in the most severe applications such as turbine blades and vanes in aircraft engines. This paper presents an economical process to make durable TBCs, called Axial Suspension Plasma Spray (ASPS). This technology combines Mettech’s axial injection plasma process and automatic suspension feed system. The resulting TBCs exhibit columnar structures with vertical cracks, similar to EB-PVD coatings. Such structures allow the TBC to compensate for thermal expansion differences between it and the base material. The ASPS process presents an economical alternative to EB-PVD to produce durable columnar TBCs.

Pini, M., A. Spinelli, V. Dossena, P. Gaetani, and F. Casella. "Dynamic Simulation of a Test Rig for Organic Vapours." In ASME 2011 5th International Conference on Energy Sustainability. ASMEDC, 2011. http://dx.doi.org/10.1115/es2011-54212.

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A blow-down facility for experimental analysis of real gases is under construction at Politecnico di Milano (Italy), in collaboration with Turboden s.r.l. and in the frame of the research project named Solar. Experiments are meant to characterize flow fields representative of expansions taking place in Organic Rankine Cycle (ORC) turbine passages. Indeed, ORC power plants represent a viable technology to exploit clean energy sources, but ORC turbines design tools still require accurate experimental data for validation. A significant improvement of turbine efficiency is expected from detailed investigations on vapour streams; in fact, ORC turbines design tools still require accurate experimental data for validation. The facility is equipped with a straight axis supersonic nozzle as a test section and a batch-closed loop plant has been designed in order to reduce investment and operational costs. Due to the batch operation, the evaluation of the time evolution of main processes involved in the cycle is of great importance. To this purpose a dynamic simulation of the test rig has been carried out using a dynamic simulator based on an object-oriented modeling language, Modelica, allowing an easy development of component models structured with a hierarchical approach. Models include control loop devices, strongly influencing processes duration. This paper presents how the test rig has been modelled, with particular emphasis on the models framework and on simulation procedure; the calculation results are finally discussed. With a lumped parameter approach, a first scheme of the facility has been built by modelling each of the three main plant section (heating, test, condensation) using components included in a self-made library. Several models, not embedded in the Modelica standard libraries, have been created using Modelica code; among them the most important has been the supersonic nozzle. In order to better describe the facility behaviour and the thermal losses, a plant calculation refinement has been carried out by the development of finite volume based one-dimensional models of ducts and reservoirs, either in radial or axial direction; in particular, a novel distributed-parameters model has been built for the heating section. All simulations have been performed using Siloxane MDM and Hydrofluorocarbon R245fa as reference fluids and FluidProp® to calculate thermodynamic properties. A quasi 1-D steady nozzle flow calculation has also been carried out by implementing FluidProp® routines in a dedicated Fortran software. Since the unsteady nozzle expansion is well approximated by a sequence of steady states, the computation provides all thermodynamic properties and velocity along the nozzle axis as a function of time. Simulation results have given a fundamental support to both plant and experiments design.