Academic literature on the topic 'Thermal solicitations'
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Journal articles on the topic "Thermal solicitations"
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Zhang, Jiamin, Daniel Dias, Qiujing Pan, Chunjing Ma, and Cristina de Hollanda Cavalcanti Tsuha. "Long-Term Thermo-Hydraulic Numerical Assessment of Thermo-Active Piles—A Case of Tropical Soils." Applied Sciences 12, no. 15 (July 29, 2022): 7653. http://dx.doi.org/10.3390/app12157653.
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Thermo-active piles are an upcoming technology for the utilization of subsurface geothermal energy in urban areas. This environmentally friendly technology has already been widespread for the heating and cooling of buildings in temperate regions, whereas in tropical regions it is still limited due to their unbalanced energy demands. This paper presents 3D thermo-hydraulic coupled numerical simulations to assess the long-term performance of thermo-active pile systems in tropical environments for different energy demands. The simulations are based on real data (in situ tests and field investigations) considering three typical thermal solicitations, thereby maintaining their practical relevance. Moreover, the energy exchange within soil control volumes is quantified based on an approach that allows calculating conductive and advective divergence. Parametric analyses regarding thermal solicitation, pile diameter, and groundwater flow are also performed. The results indicate that groundwater flow plays the most important role in improving the thermal balance of thermo-active piles.
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Crăciun, Radu Cristian, Sergiu Stanciu, Ramona Cimpoeşu, Florin Săndulache, Adela Ioana Ursanu Dragos, and Mihai Axinte. "Smart Alloys for Automotive Bumpers." Applied Mechanics and Materials 809-810 (November 2015): 578–83. http://dx.doi.org/10.4028/www.scientific.net/amm.809-810.578.
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Bumper beam absorbs the accidental kinetic energy by deflection in low-speed impact and by deformation in high-speed impact. Based on the last years necessity of lighter materials and safer usage of vehicles we try to come with a new class of materials for bumper systems. Analyze of metallic materials is cheaper when the analyze take place on a computer avoiding the metallic loss or energy consume. We present few results obtained in Catia software about the behavior of some metallic materials under external solicitations in function of the mechanical properties of metallic elements, geometry of the element, restrains and solicitation points. Shape memory alloy are smart materials that can use the external mechanical energy damping to thermal energy in bumper applications. In martensite to austenite domain we observe an increase of damping mechanical capacity with possible applications in bumper systems.
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Mustapha, Feriel, Damien Guilbert, and Mohammed El-Ganaoui. "Investigation of Electrical and Thermal Performance of a Commercial PEM Electrolyzer under Dynamic Solicitations." Clean Technologies 4, no. 4 (September 26, 2022): 931–41. http://dx.doi.org/10.3390/cleantechnol4040057.
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Hydrogen generation through electrolyzers has gained a growing interest from researchers and industries to decarbonize transportation and electricity production. The performance of electrolyzers is strongly dependent on their operating conditions, such as the supply current, temperature, and pressure. To meet near-zero emissions, the electrolyzer must be supplied by low-carbon energy sources. Therefore, renewable energy sources must be considered. However, these sources are strongly linked with the weather conditions, so they have a high dynamic behavior. Therefore, this article is focused on the investigation of the effects of these dynamic solicitations on the electrical and thermal performance of electrolyzers. In this study, a proton exchange membrane (PEM) has been chosen to carry out this investigation. Experimental tests have been performed, emphasizing the relationship between the electrical and thermal performance of the PEM electrolyzer. The purpose of this work is to provide an optimal scenario of the operation of the electrolyzer under dynamic solicitations and consequently, to decrease the degradation of the electrolyzer.
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Rammal, D., H. Mroueh, and S. Burlon. "Impact of thermal solicitations on the design of energy piles." Renewable and Sustainable Energy Reviews 92 (September 2018): 111–20. http://dx.doi.org/10.1016/j.rser.2018.04.049.
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Antonaci, Paola, and Davide Masera. "Mechanical Behavior of Structural Concrete Made with Recycled Aggregates from Tunnel Excavation." Key Engineering Materials 452-453 (November 2010): 121–24. http://dx.doi.org/10.4028/www.scientific.net/kem.452-453.121.
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The results of an experimental study concerning the behavior of concretes made with recycled aggregates under repeated mechanical and thermal actions are presented. A comparison with the performances achieved by similar concretes made with traditional aggregates in the same working conditions eventually made it possible to estimate the actual quality and durability of the recycled concretes examined and identify possible limitations in their use. The laboratory protocol here adopted is suggested as a practical experimental procedure to test hardened concretes and pre-qualify their performances with respect to compressive actions and thermal solicitations.
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Maghsoodi, S., and O. Cuisinier. "Energy pile skin friction at interface in clays under temperature cycles." Géotechnique Letters 12, no. 3 (September 1, 2022): 1–24. http://dx.doi.org/10.1680/jgele.21.00153.
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In energy geostructures the long-term shaft resistance is affected by cyclic thermo-mechanical loads associated to structural loads and cyclic thermal solicitations. This study aims to investigate the effect of monotonic and cyclic thermal loads on normally consolidated and overconsolidated kaolin clay-rough steel interface. The peak shear stress of interface increased with temperature while the critical state shear strength remained unchanged. For cyclic temperature tests, with applying 10 temperature cycles (5-60°C) to normally consolidated kaolin clay interface, significant thermal contraction was observed but the shear strength increased as much as one single heating test. Normally consolidated interface contracted upon heating while overconsolidated samples dilated. These results highlighted the impact of thermal cycles on clayey interface which was stress history dependent.
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Le Touz, Nicolas, Jean Dumoulin, Gianluca Gennarelli, and Francesco Soldovieri. "A joint thermal and electromagnetic diagnostics approach for the inspection of thick walls." Geoscientific Instrumentation, Methods and Data Systems 6, no. 1 (February 8, 2017): 81–92. http://dx.doi.org/10.5194/gi-6-81-2017.
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Abstract. In this study, we present an inversion approach to detect and localize inclusions in thick walls under natural solicitations. The approach is based on a preliminary analysis of surface temperature field evolution with time (for instance acquired by infrared thermography); subsequently, this analysis is improved by taking advantage of a priori information provided by ground-penetrating radar reconstruction of the structure under investigation. In this way, it is possible to improve the accuracy of the images achievable with the stand-alone thermal reconstruction method in the case of quasi-periodic natural excitation.
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Chacón, L., J. Viña, A. Argüelles, R. Zenasni, and I. Viña. "Evaluación del comportamiento mecánico de compuestos PEI â fibra de vidrio ante solicitaciones térmicas." Boletín de la Sociedad Española de Cerámica y Vidrio 43, no. 2 (April 30, 2004): 420–22. http://dx.doi.org/10.3989/cyv.2004.v43.i2.557.
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Baldinelli, Giorgio, Francesco Bianchi, Agnieszka A. Lechowska, and Jacek A. Schnotale. "Dynamic thermal properties of building components: Hot box experimental assessment under different solicitations." Energy and Buildings 168 (June 2018): 1–8. http://dx.doi.org/10.1016/j.enbuild.2018.03.001.
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Seng, Billy, Camille Magniont, Sandra Gallego, and Sylvie Lorente. "Behavior of a hemp-based concrete wall under dynamic thermal and hygric solicitations." Energy and Buildings 232 (February 2021): 110669. http://dx.doi.org/10.1016/j.enbuild.2020.110669.
Full textDissertations / Theses on the topic "Thermal solicitations"
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Martin, Benoît. "Dynamique des transferts d’humidité au sein de l’épicéa commun (Picea abies (L.) Karst.) : mesures par imagerie X et simulations numériques." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0044.
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Les outils numériques sont couramment utilisés par les entreprises de construction pour concevoir et valider les systèmes constructifs en vue de répondre aux exigences thermiques et environnementales des bâtiments. Dans le cas du bois massif, des disparités demeurent entre les simulations numériques et les données expérimentales vis-à-vis des transferts d’humidités. Leur bonne prise en compte est pourtant une donnée essentielle pour garantir la pérennité des ouvrages bois et assurer les performances thermiques de l’ouvrage. Ce travail vise à mieux comprendre les transferts d’humidités au sein du bois massif en vue d’améliorer la capacité prédictive des modèles. Ainsi, plusieurs dispositifs expérimentaux ont été développés pour étudier la dynamique des transferts d’humidité à l’échelle matériau à l’aide de l’imagerie X. Dans un premier temps, des expériences d’imbibition ont été menées pour étudier la migration capillaire dans des échantillons d’épicéa afin de reproduire une exposition à de l’eau liquide lors de la phase de construction. Les images tomographiques 3D ont permis de suivre le cheminement de l’eau et ainsi de mieux comprendre l’effet de l’anatomie sur les transferts. Dans un second temps, la dynamique des transferts d’humidité en conditions non‑isothermes a été étudiée en appliquant une séquence de sollicitations thermiques aux bornes d’un échantillon cylindrique se rapprochant des conditions rencontrées dans une paroi extérieure. L’évolution spatio-temporelle de la teneur en eau au sein de l’échantillon – initialement avec une teneur en eau homogène – a mis en évidence l’effet de la température sur la redistribution de l’humidité. Enfin, ces données expérimentales ont été confrontées aux valeurs issues de simulations numériques suivant différentes configurations illustrant les capacités prédictives et les limites des modèles utilisant une formulation macroscopique pour simuler les transferts couplés chaleur-masse dans le milieu poreuxNumerical tools are commonly used by construction companies to design and validate building systems to meet thermal and environmental requirements of buildings. In the case of solid wood, discrepancies remain between numerical simulations and experimental data regarding moisture transfer. However, their correct consideration is essential to guarantee the durability of wood structures and ensure their thermal performance. This work aims to better understand moisture transfer in solid wood in order to improve the predictive capacity of models. For this purpose, several experimental setups were developed to study the dynamics of moisture transfer in wood samples using X-ray imaging. Firstly, imbibition experiments were conducted to study capillary migration in spruce samples to reproduce exposure of wooden construction components to liquid water during the construction phase. The results – from 3D µCT images – allowed to follow the liquid pathways in the pore network of wood and thus to better understand the effect of anatomy on the water migration. Secondly, the dynamics of moisture transfer under non‑isothermal conditions was studied by applying a sequence of thermal solicitations to the ends of a cylindrical sample similar to the conditions encountered in an external wall. The spatio‑temporal evolution of the moisture content within the sample – initially with a homogeneous moisture content – showed the effect of temperature on the moisture redistribution. Finally, these experimental data were compared with values from numerical simulations in different configurations, illustrating the predictive capacities and limitations of models using a macroscopic formulation to simulate coupled heat-mass transfers in a porous medium
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Laibi, Babatounde. "Comportement hygro-thermo-mécanique de matériaux structuraux pour la construction associant des fibres de kénaf à des terres argileuses." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMC265/document.
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Les briques de terre compressée (BTC) à la façon traditionnelle au Bénin présentent de piètres propriétés mécaniques, ce qui explique que les populations recourent aux parpaings de ciment relativement trop couteux et dont l’emploi affecte fortement les ressources en eau et en énergie. Ce travail propose des pistes d’amélioration des BTC pour l’écoconstruction par l’ajout de fibres végétales à des sols usités localement pour la construction. Cette stratégie permet de valoriser les matières premières minérales et végétales dans un domaine d’activités qui concerne une grande partie de la population. Dans un premier temps, un sol a été choisi d’après sa composition chimique, ses propriétés physiques, mécaniques et technologiques. Le choix de la fibre de kénaf pour le renforcement de la matrice minérale se justifie par ses excellentes propriétés mécaniques spécifiques et sa disponibilité à très faible coût. Les effets des fibres sur le comportement du sol au jeune âge, puis sur les comportements mécanique et hygrothermique des matériaux consolidés sous 5 MPa (pression applicable avec les équipements facilement disponibles au Bénin), ont été étudiés pour trois taux massiques de fibres (0,5%; 1% et 1,5% relativement au sol) dans différentes longueurs (5, 10, 20 et 30 mm). Les résultats indiquent une nette amélioration du comportement mécanique des BTC renforcés par le kénaf en termes des résistances à la flexion et à la compression, et de la résistance à la rupture catastrophique (comportement pseudo ductile). Les résultats les plus élevés sont obtenus pour une teneur de 0,5% de fibres de longueur 30 mm. L’ajout de ciment seul au sol fibré (taux de 3, 5 et 7%) ou de ciment associé au laitier de haut fourneau (taux de 3-5% et 5-10%, respectivement) permet en sus d’améliorer de façon importante la résistance à la prise d’eau. Les meilleurs résultats sont obtenus avec 5% de ciment et 10% de laitier de haut fourneau. Les mesures réalisées en chambre biclimatique ont permis de caractériser les matériaux comme paroi séparatrice, en étudiant les transferts de chaleur et de vapeur d’eau. Les résultats mettent en évidence l’effet significatif de l’ajout d’un liant au BTC : L’ajout d’un liant diminue le déphasage et augmente l’atténuation du matériau. Les meilleurs résultats de comportement hygrothermique sont obtenus pour le sol fibré.Cette étude démontre qu’il est possible de produire au Bénin, à partir de matières premières locales et avec des équipements peu onéreux, des éco-matériaux aux propriétés mécaniques et hygrothermiques satisfaisantes pour la construction d’habitat de type R+1Traditional Compressed Earth Blocks (CEB) in the Republic of Benin have poor mechanical properties, this justifies why people rely on relatively expensive cement blocks; the use of which greatly affects resources such as water and energy. In this work we have proposed ways to enhance CEB properties for eco-construction by adding plant fibers to locally used construction's soils. This strategy makes it possible to value mineral and vegetable raw materials in a field of an activity that is common to a large part of the population. At first, a soil was chosen according to its chemical composition, its physical, mechanical and technological properties. The choice of kenaf fiber for the reinforcement of the mineral matrix isjustified by its excellent specific mechanical properties and its availability at very low cost. The effects of fibers on soil behavior at young age and on the mechanical and hygrothermal behavior of consolidated materials under 5 MPa (pressure applicable with equipment readily available in Benin) were studied for three mass content of fibers relatively to the soil (0.5% 1% and 1.5%) and different lengths (5, 10, 20 and 30 mm). The results indicated a remarkable improvement in the mechanical behavior of kenaf-reinforced CEBs in terms of flexural and compressive strengths and tolerance to damage. The highest results were obtained with 0.5% of fibers 30 mm long. The addition of a binder (3, 5 and 7% of cement) or (3-5% and 5-10% of cement and blast furnace slag mix) allowed an important reduction in water uptake. The best mechanical results were obtained for a biocomposite made up with BAK soil, 0.5% of flax fibers 30 mm long and a mix of 5% cement and 10% blast furnace slag. Measurements carried out in a biclimatic chamber made it possible to characterize the hydric and thermal behavior of the soil-based materials. The addition of a binder decreases the phase shift and increases the attenuation of the material. These different results show that it is possible to produce in Benin with the available equipment, CEB with mechanical and hygrothermal properties sufficient enought for the construction of type R + 1 habitat
Conference papers on the topic "Thermal solicitations"
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Long Le Tran, Hoang, Anne-Lise Cristol, Vincent Magnier, and Jérôme Hosdez. "Relationship between Mechanical Behavior and Microstructure Evolution of Sintered Metallic Brake Pad under the Effect of Thermomechanical Stresses." In EuroBrake 2021. FISITA, 2021. http://dx.doi.org/10.46720/4525694eb2021-fbr-009.
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Sintered metallic composite is widely used as brake pad material for high energy railway thanks for its good resistance to severe solicitations caused by braking loads. Despite its efficiency, the degradation of the material properties under the effect of brake loads has been noticed in literature which is undoubtedly induced by the microstructure evolution. However, the microstructure evolution and its relation with mechanical behavior have so far not been intensively investigated due to the complexity of braking solicitations. To solve the problem without tackling it in all its complexity, two experimental tests were proposed where physics are decoupled; but still inspired by the braking sequence in terms of applied temperature and compressive load. The first one is the thermal solicitation test where a temperature gradient from 400°C to 540°C was applied to the material. The second one is the thermomechanical test where a compressive load at 20 MPa was applied under the same thermal gradient. The experiment time is fixed for two minutes, equivalent to the time of one braking stroke. Besides, the local microstructure evolution of the sintered metallic brake pad was characterized by Electron Microscopy (SEM) coupling with Energy-dispersive X-ray Spectroscopy (EDS) and X-ray microtomography. The evolution of mechanical properties was characterized by a series of compressive tests equipped with a Digital Image Correlation (DIC) for analyzing deformation behavior. Based on the deformation behavior characteristics, the considered thermal and mechanical solicitations have no separate effect on the mechanical properties of the material. The sole evolution of mechanical behavior is due to the coupled thermomechanical solicitation, which increases the hardness of friction material. From the strain field analysis, the evolution takes place on the strain lines determined by the compressive test, which strongly depends on the distribution of graphite inclusions in the microstructure. The change in mechanical behavior is induced by the local microstructure evolution. Indeed, thermomechanical stresses cause the densification of the graphite in the normal direction, this structural change induce some shear cracks in the basal plane. In terms of the metallic matrix, the segregation of carbon in steel is investigated as a reason for the increased stiffness.
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McCabe, Joseph. "Optimization of Photovoltaic/Thermal Collectors." In ASME 2004 International Solar Energy Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/isec2004-65180.
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Recent designs in the Solar Decathlon have incorporated solar electric modules with heat capture. Zero Energy Buildings (ZEB) solicitations through the National Renewable Energy Laboratory (NREL) have recently awarded photovoltaic / thermal (PV/T) projects incorporating air and fluid based heat transfer mediums. This paper introduces the PV/T collector with a quick history of four different research and development projects starting with the Massachusetts Institute of Technology (MIT) in 1978. Suggestions for engineering design and performance guidelines are provided. A demonstration of a zero glazed thin film amorphous silicon photovoltaic module with air as the fluid transfer medium, captured off the backside, is presented. The paper provides suggestions on applications and appropriate environments for various PV/T collector types.
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Pasutto, Thomas, Christophe Pe´niguel, Marc Sakiz, and Jean-Michel Ste´phan. "Unsteady Fluid/Solid Numerical Simulations to Evaluate Thermal Solicitations in PWR Nuclear Plant Mixing Zones." In ASME 2005 Pressure Vessels and Piping Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/pvp2005-71285.
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Thermal fatigue of the coolant circuits of PWR plants is a major issue for nuclear safety. The problem is especially accute in mixing zones, like T-junctions, where large differences in water temperature between the two inlets and high levels of turbulence can lead to large temperature fluctuations at the wall. Until recently, studies on the matter had been tackled at EDF using steady methods: the fluid flow was solved with a CFD code using an averaged turbulence model, which led to the knowledge of the mean temperature and temperature variance at each point of the wall. But, being based on averaged quantities, this method could not reproduce the unsteady and 3D effects of the problem, like phase lag in temperature oscillations between two points, which can generate important stresses. Benefiting from advances in computer power and turbulence modelling, a new methodology is now applied, that allows to take these effects into account. The CFD tool Code_Saturne, developped at EDF, is used to solve the fluid flow using an unsteady L.E.S. approach. It is coupled with the thermal code Syrthes, which propagates the temperature fluctuations into the wall thickness. The instantaneous temperature field inside the wall can then be extracted and used for structure mechanics computations (mainly with EDF thermomechanics tool Code_Aster, see joint paper [1]). The purpose of this paper is to present the application of this methodology to the simulation of a straight T-junction mockup, similar to the Residual Heat Remover (RHR) junction found in N4 type PWR nuclear plants, and designed to study thermal striping and cracks propagation. The results are generally in good agreement with the measurements; yet, in certain areas of the flow, progress is still needed in L.E.S. modelling and in the treatment of instantaneous heat transfer at the wall.
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Taher, Bilal, Said Abboudi, and Rafic Youness. "Damage of Thermo-Elasto-Plastic Multimaterial Under Thermal Cycling Conditions." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68815.
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The increasing of the temperature in the multi-material solicited with thermal and mechanical charges leads to surpass the load of elastic constraint, so we have to apply the thermo-elasto-plastic behavior. The increasing need of structures having multiple functions orientates designers to combine materials in order to obtain, according to coupling scales, multi-materials structures. The lifetime of these structures represents a one of the main decisive element for offices and manufacturers studies. The results of this work should be added to the set of functional charges to obtain an optimal and final decision on the design of the product. In this study, a numerical analysis conducted by finite elements method of thermo-elasto-plastic behavior of these type of materials and their damage under thermal cyclic solicitations. The study is led in two dimensions (r, z) on a cylindrical material constituted of two layers (stainless steel, Steel), subjected to a variable heat flux at the internal surface and an exchange with the ambient at the external surface. Other faces are isolated. The sample is fixed in the axial direction and free in the radial direction. The damage model is based on the works of Lemaiˆtre and Chaboche. Numerical results are presented for periodic heat flux and for different thickness of the material. The study is concluded by optimizing of the thickness of materials according to the total lifetime caused by thermo-elasto-plastic effect.
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Taher, Bilal, Said Abboudi, and Rafic Youness. "Effect of Frequency and Shape of Thermal Cycling on the Damage of Multi-Material Under Thermo-Elasto-Plastic Behaviour." In ASME 2009 Pressure Vessels and Piping Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/pvp2009-77370.
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In this study, we propose a numerical analysis of the thermo-elasto-plastic behavior of a multi-material and its damage under thermal cyclic solicitations. The study is done in two dimensions on a cylindrical multi-material subjected to a periodic heat flux on the internal face and to a convective heat transfer condition on the opposite external face. Lateral faces are supposed to be isolated. The sample is supposed to be fixed in the axial direction and free in the other. The damage model is based on the works of Lemaiˆtre and Chaboche. Numerical results are presented for different shapes of heat flux cycling (triangular, square and sinusoidal excitations, function of time and space) and for a range of periods. We do a comparison of the multi-material damage under these different thermal excitations. The study is concluded by some advice on the use and avoidance of some values of periods, and shapes for the thermal load excitation, in order to obtain the maximum lifetime of the multi-material under thermo-elasto-plastic behavior.
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Taher, Bilal, Said Abboudi, and Rafik Youness. "Study of the Homogenization Technique in a Two-Layer Cylindrical Material." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-44084.
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The objective of this study is to analyze the thermo-mechanical behavior of a two-layer cylindrical material, subjected to variable thermal solicitations. The thermo-mechanical coupling is done by the consideration of the spatiotemporal variations of the temperature in the mechanical problem on one hand, and by means of the variations of the thermal and mechanical properties on the other hand. The study is led in two dimensions (r, z) on a cylindrical multi-material consisting of two layers subjected to a periodic or constant heat flux on one face, and to an exchange condition on the opposite face. Other faces are supposed to be insulated. We compare two approaches of the problem, the first one is a local approach based on a theoretical study of the thermal and mechanical fields (thermal transfer and constraints) and the second approach is based on the notion of equivalence of the thermo-physical properties of both layers to only one. Thus, this second approach is a homogenization of the multi-material in a single fictitious material possessing the same thermo-mechanical behavior.
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Taher, Bilal, Rafic Youne`s, and Said Abboudi. "Numerical Analysis of Thermomechanical Behavior of a Multimaterial Under Thermal Cycling Conditions." In ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/pvp2006-icpvt-11-93495.
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The increasing need of structures having multiple functions orientates designers to combine materials in order to obtain, according to coupling scales, multi-materials structures. The lifetime of these structures represents the essential decisive element for study offices and manufacturers. The results of this work should add to the set of functional charges and constraints of resistance, the improvement of the lifetime as an objective to optimize a multi-material. In this study, we propose a numerical analysis by the finite elements method of the thermo mechanical behavior of these materials and their damage under thermal cyclic solicitations. The sample is a two-dimensional plate constituted of two different isotropic layers (steel, aluminum) submitted to variable thermal conditions (heat flux condition on one side and convection exchange condition on the opposite side). The sample is supposed to be fixed in one direction and free in the other. The damage model is based on the works of Lemaiˆtre and Chaboche [8]. Numerical results are presented for different forms of heat flux cycling (triangular, square and sinusoidal excitations) with a comparison of the multi-material damage for each excitation. The study is concluded by an empirical optimizing of the thickness of materials according to the total lifetime caused by thermo-mechanical effect.
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Chen, L., J. Wang, Y. M. Liu, F. Collin, and J. L. Xie. "Thermo-Hydro-Mechanical Simulation of a Heating and Hydration Experimental Study (the China-Mock-Up) in GMZ Bentonite." In ASME 2011 14th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2011. http://dx.doi.org/10.1115/icem2011-59212.
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This paper presents a numerical study of the China-Mock-up test, with the purpose of evaluating the performance of Gaomiaozi (GMZ) bentonite under coupled thermo-hydro-mechanical (THM) conditions. In the paper, the basic THM characteristics of GMZ bentonite are presented first. The formulation of coupling heat, moisture (liquid water and water vapour) and air transfer is given. The model of Alonso-Gens (1) is incorporated to reproduce the mechanical behavior of the GMZ bentonite under unsaturated conditions. With the parameters determined from experimental investigations, numerical simulations of the China-Mock-up test are carried out using the code of LAGAMINE. Owing to the lack of experimental data at present stage, a qualitative analysis of the predictive results is realized. The results suggest that the proposed model is able to reproduce the mechanical behavior of GMZ bentonite, and to predict moisture and air motions under thermal solicitations.
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Cesari, F. G., and P. Battistella. "Design by Formula of Power Steam Line Equipped by Energy Dissipative Devices." In 10th International Conference on Nuclear Engineering. ASMEDC, 2002. http://dx.doi.org/10.1115/icone10-22472.
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To evaluate the ability of passive devices in protecting nuclear piping during earthquake a theoretical/experimental campaign has been performed. By means of numerical runs the effect of viscous dampers application on most critical points of a power plant steamline has been evaluated. The principle is to employ a local safety solution against heavy dynamic solicitations placing passive devices in crotch region of bends. The devices location corresponds to an in plane position in respect of the curve. Considerations on structural configuration and stress/strain states are also presented with the aim to respect the philosophy of design/verification requirements stated by the ASME Sct. III Cl.1 code. For experimental tests a C mock-up, whose sizes are derived by a thermal plant steamline, has been suggested and studied [1]. Comparison of numerical data on piping with/without dissipative elements are also included. The impact on the whole structure has been also taken into account. Some of the results included in the paper have been obtained in the E.U. contract named REEDS.
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Boumediene, Naima, Florence Collet, Sylvie Prétot, Lazhar Ayed, and Sami Elaoud. "Experimental and Numerical Study of Hygrothermal Behaviour of a Washing Fines Hemp Test Wall." In 4th International Conference on Bio-Based Building Materials. Switzerland: Trans Tech Publications Ltd, 2022. http://dx.doi.org/10.4028/www.scientific.net/cta.1.195.
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Bio-based materials are a promising tracks that offer thermal and environmental performances in order to reduce the consumption of energy and of non-renewable resources. For this purpose, in a previous study, the LGCGM worked on the development of Washing Fines Hemp composites (WFH) and characterized them on multiphysical points of view. Such materials show low thermal conductivity and high moisture buffer ability. In order to characterize their hygrothermal behavior at wall scale, a test wall is set up in an air-conditioned bi-climatic test room to simulate indoor and outdoor climates. This paper investigates the characterization of hygrothermal behavior of Washing Fines Hemp wall under typical Tunisian summer climate. It consists in an experimental study, supplemented by numerical simulation performed with WUFI Pro V6.5 software. The experimental hygrothermal response of the wall to such solicitations is analyzed from the temperature and relative humidity kinetics at several positions in the wall and from temperature and vapor pressure profiles. It shows that for daily cycles the two thirds of the thickness of the wall on the exterior side are active, as well regarding heat and moisture phenomena. More sorption-desorption phenomena are highlighted. The numerical results are consistent with experimental data for temperature and underestimate vapor pressure in the inner part of the wall.