Literatura académica sobre el tema "Rupture Speed"
Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros
Consulte las listas temáticas de artículos, libros, tesis, actas de conferencias y otras fuentes académicas sobre el tema "Rupture Speed".
Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.
También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.
Artículos de revistas sobre el tema "Rupture Speed"
1
Datta, Sanjoy, Radek Stoček y Evghenii Harea. "Parametrical Function Describing Influences of the Redistribution of Incorporated Oil for Rupture Process Reconstruction in Rubber". Polymers 15, n.º 6 (9 de marzo de 2023): 1363. http://dx.doi.org/10.3390/polym15061363.
Texto completoResumen
The present work is focused on finding (i) the tearing energy at rupture and (ii) the redistribution of incorporated paraffin oil on the ruptured surfaces as functions of (a) the initial oil concentration and (b) the speed of deformation to the total rupture in a uniaxially induced deformation to rupture on an initially homogeneously oil incorporated styrene butadiene rubber (SBR) matrix. The aim is to understand the deforming speed of the rupture by calculating the concentration of the redistributed oil after rupture using infrared (IR) spectroscopy in an advanced continuation of a previously published work. The redistribution of the oil after tensile rupture for samples that have three different initial oil concentrations with a control sample that has no initial oil has been studied at three defined deformation speeds of rupture along with a cryo-ruptured sample. Single-edge notched tensile (SENT) specimens were used in the study. Parametric fittings of data at different deformation speeds were used to relate the concentration of the initial oil against the concentration of the redistributed oil. The novelty of this work is in the use of a simple IR spectroscopic method to reconstruct a fractographic process to rupture in relation to the speed of the deformation to rupture.
2
Datta, Sanjoy, Radek Stoček, Evghenii Harea, Ondřej Kratina y Martin Stěnička. "Configuration of Novel Experimental Fractographic Reverse Engineering Approach Based on Relationship between Spectroscopy of Ruptured Surface and Fracture Behaviour of Rubber Sample". Materials 13, n.º 19 (7 de octubre de 2020): 4445. http://dx.doi.org/10.3390/ma13194445.
Texto completoResumen
A novel fractographic approach based on a combination of (i) mechanical behavior of cured rubber in uniaxial tensile loading and (ii) spectroscopy of fracture on a ruptured surface was experimentally validated. This approach related the migration of paraffin oil from a matrix to the ruptured rubber surface, to the tearing energy related to the deformation speed responsible for total rubber sample rupture, and the approach itself was configured experimentally. It was evaluated on cured natural rubber (NR) for two different paraffin oil concentrations. Single edge notched tensile (SENT) samples were subjected to uniaxial tensile loadings at two different deformation speeds. First, the tearing energy as a function of deformation speed was determined for each defined oil concentration. Secondly, at specific locations on the ruptured surfaces, infrared (IR) spectroscopy was performed to quantify a characteristic absorbance peak height of migrated paraffin oil during the rupture process. The results of the IR analyses were related to the deformation speed to understand the relation between the amount of migrated paraffin oil during the fracture process and the deformation speed which brought about such a fracture. This novel approach enhanced the reverse engineering process of rubber fracture related to the cause of tearing energies during critical failure.
3
Sun, Qi-Long, Lei Sun, Xiao-Wen Wang, Jia-Ling Fang, Hai-Yan Kong, Ji-Huan He y Hu Gu. "Jet speed in bubble rupture". Thermal Science 22, n.º 1 Part A (2018): 47–50. http://dx.doi.org/10.2298/tsci151202149s.
Texto completo
4
Kawamura, Hikaru, Koji Yoshimura y Shingo Kakui. "Nature of the high-speed rupture of the two-dimensional Burridge–Knopoff model of earthquakes". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, n.º 2136 (26 de noviembre de 2018): 20170391. http://dx.doi.org/10.1098/rsta.2017.0391.
Texto completoResumen
The nature of the high-speed rupture or the main shock of the Burridge–Knopoff spring-block model in two dimensions obeying the rate- and state-dependent friction law is studied by means of extensive computer simulations. It is found that the rupture propagation in larger events is highly anisotropic and irregular in shape on longer length scales, although the model is completely uniform and the emergent rupture-propagation velocity is nearly constant everywhere at the rupture front. The manner of the rupture propagation sometimes mimics the successive ruptures of neighbouring ‘asperities’ observed in real, large earthquakes. Large events tend to be unilateral, with its epicentre lying at the rim of its rupture zone. The epicentre site of a large event is also located next to the rim of the rupture zone of some past event. Event-size distributions are computed and discussed in comparison with those of the corresponding one-dimensional model. The magnitude distribution exhibits a power-law behaviour resembling the Gutenberg–Richter law for smaller magnitudes, which changes over to a more characteristic behaviour for larger magnitudes. For very large events, the rupture-length distribution exhibits mutually different behaviours in one dimension and in two dimensions, reflecting the difference in the underlying geometry. This article is part of the theme issue ‘Statistical physics of fracture and earthquakes’.
5
Ye, Lingling, Thorne Lay, Hiroo Kanamori, Zhongwen Zhan y Zacharie Duputel. "Diverse rupture processes in the 2015 Peru deep earthquake doublet". Science Advances 2, n.º 6 (junio de 2016): e1600581. http://dx.doi.org/10.1126/sciadv.1600581.
Texto completoResumen
Earthquakes in deeply subducted oceanic lithosphere can involve either brittle or dissipative ruptures. On 24 November 2015, two deep (606 and 622 km) magnitude 7.5 and 7.6 earthquakes occurred 316 s and 55 km apart. The first event (E1) was a brittle rupture with a sequence of comparable-size subevents extending unilaterally ~50 km southward with a rupture speed of ~4.5 km/s. This earthquake triggered several aftershocks to the north along with the other major event (E2), which had 40% larger seismic moment and the same duration (~20 s), but much smaller rupture area and lower rupture speed than E1, indicating a more dissipative rupture. A minor energy release ~12 s after E1 near the E2 hypocenter, possibly initiated by the S wave from E1, and a clear aftershock ~165 s after E1 also near the E2 hypocenter, suggest that E2 was likely dynamically triggered. Differences in deep earthquake rupture behavior are commonly attributed to variations in thermal state between subduction zones. However, the marked difference in rupture behavior of the nearby Peru doublet events suggests that local variations of stress state and material properties significantly contribute to diverse behavior of deep earthquakes.
6
Porcelli, Matthew, Oksana Prychyna, Andrew Rosenthal y Joseph DeCostanza. "Hepatothorax: A Rare Outcome of High-Speed Trauma". Case Reports in Emergency Medicine 2011 (2011): 1–3. http://dx.doi.org/10.1155/2011/905641.
Texto completoResumen
Diaphragmatic ruptures are the result of severe blunt trauma or penetrating trauma. Motor vehicle crashes are a common mechanism associated with blunt diaphragmatic rupture (BDR). Incorporating diagnostic tools and laparotomy assist in the diagnosis and treatment of BDR. However, diagnosing BDR can be a challenge for practitioners. Early diagnosis and treatment improve the patient's outcomes. This paper details the events of a patient received in a level I trauma unit.
7
Yuan, Jie, Jinting Wang y Shoubiao Zhu. "Effects of Barriers on Fault Rupture Process and Strong Ground Motion Based on Various Friction Laws". Applied Sciences 10, n.º 5 (2 de marzo de 2020): 1687. http://dx.doi.org/10.3390/app10051687.
Texto completoResumen
A barrier may induce a supershear rupture on a fault. This paper focuses on two questions: One is whether the existence of a barrier accelerates the propagation speed of a whole fault rupture, and the other is what are the effects of friction laws and strength of a barrier on the rupture propagation process. For these purposes, classical slip-weakening, rate-state, and modified slip-weakening friction laws are employed to simulate the effect of a barrier on the fault rupture process. The simulation results showed that the rupture speed of the fault obviously decreases when the rupture front propagates to the barriers, and the rupture speed obviously increases when the rupture front leaves barriers. It was also found that a barrier on a fault may induce a supershear rupture via the rate-state friction law. The simulation results also showed that with the increase of barrier strength, the rupture speed near barriers fluctuates more and more; when the barrier strength exceeds a certain level, a supershear rupture area appears on the fault; with the increase of barrier strength, the propagation distance of the rupture at supershear wave velocity correspondingly increases. In addition, with the increase of barrier strength, the overall rupture duration of the fault slightly increases. This indicates that a barrier cannot shorten the total duration of a fault rupture. Though a barrier will lead to a supershear rupture, it just regulates the distribution of the rupture speed on the fault surface. Moreover, with the increase of barrier strength, the peak ground acceleration caused by rupture through the barrier also increases, indicating that the existence of a barrier may lead to the intensification of seismic hazards.
8
Zhu, Likuan, Boyan Song y Zhen Long Wang. "Computational Fluid Dynamics Analysis on Rupture of Gas Bubble". Applied Mechanics and Materials 339 (julio de 2013): 468–73. http://dx.doi.org/10.4028/www.scientific.net/amm.339.468.
Texto completoResumen
Hydrodynamic information of the flow occurring as a bubble ruptures at a gas liquid interface has being obtained from computer simulations. The simulation result is verified by conducting high-speed photography experiment. Process of bubble rupture is clearly captured with simulation and experiment. Shear force generated by bubble rupture increases along with decrease of bursting bubble diameter or increase of coefficient of surface tension. The maximum average shear force ranges from 0.97Pa to 1.91Pa, when bursting bubble diameter changes from 2mm to 10mm.
9
Hudock, Paul A. y Takeshi Imajo. "Impact Speed and Rupture of the Aorta". American Journal of Forensic Medicine and Pathology 10, n.º 2 (junio de 1989): 181. http://dx.doi.org/10.1097/00000433-198906000-00019.
Texto completo
10
Heller, Georg, Franz F. Immer, Hannu Savolainen, Eva S. Kraehenbuehl, Thierry P. Carrel y Juerg Schmidli. "Aortic Rupture in High-Speed Skiing Crashes". Journal of Trauma: Injury, Infection, and Critical Care 61, n.º 4 (octubre de 2006): 979–80. http://dx.doi.org/10.1097/01.ta.0000228878.09533.99.
Texto completoTesis sobre el tema "Rupture Speed"
1
Yamada, Takuji. "Rupture speed and apparent stress of small earthquakes". 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/145096.
Texto completoResumen
Kyoto University (京都大学)0048
新制・課程博士
博士(理学)
甲第11330号
理博第2888号
新制||理||1431(附属図書館)
22973
UT51-2005-D81
京都大学大学院理学研究科地球惑星科学専攻
(主査)教授 Mori James Jiro, 助教授 中西 一郎, 教授 竹本 修三
学位規則第4条第1項該当
2
Tilière, Guillaume de. "Managing projects with strong technological rupture case of high-speed ground transportation systems /". Lausanne, Switzerland : EPFL, 2002. http://worldcat.org/oclc/50471123/viewonline.
Texto completoResumen
Thesis (Civil Engineering)--École polytechnique fédérale de Lausanne, 2002.PDF document ; contains 333 pages, with illustrations and charts (some col.). "Thèse no. 2568 (2002)." Includes bibliographical references.
3
Leroux, Armand. "Modèle multiaxial d'endommagement anisotrope : gestion numérique de la rupture et application à la ruine de structures en béton armé sous impacts". Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2012. http://tel.archives-ouvertes.fr/tel-00824314.
Texto completoResumen
Le besoin de prédire le comportement mécanique des structures industrielles en béton armé et d'évaluer leur niveau d'endommagement en conditions extrêmes sous l'action de chargements dynamiques violents nécessite de faire appel à la simulation numérique utilisant des modèles de matériaux fiables et robustes. Dans cette thèse, le modèle d'endommagement anisotrope induit utilisant une variable tensorielle d'ordre 2 est étendu aux cas de chargements peu confinés à l'aide d'un nouveau critère modulaire formulé en contraintes. Grâce au mécanisme de visco-endommagement, le modèle traite toute la gamme de vitesses de sollicitation envisagée pour des structures en béton armé. Le comportement cyclique avec refermeture des fissures est pris en compte et l'endommagement peut atteindre 1 exactement dans une ou plusieurs directions grâce à une nouvelle gestion de la rupture. Le calcul d'un tirant a montré que cette procédure est indispensable pour plastifier l'acier et éviter un endommagement généralisé du béton. Lors du volet expérimental de la thèse, des essais de caractérisation du béton et des essais d'arrachement ont été réalisés en coopération avec le Département Génie Civil de l'ENS Cachan, suivis des essais d'impact sur poutres sur la tour de chute Orion au laboratoire DYN du CEA à Saclay. Avec une prise en compte pragmatique de l'interface acier-béton, la comparaison des calculs et des essais a montré qu'il était nécessaire de disposer d'un modèle de liaison acier-béton pour éviter un endommagement trop important du béton au voisinage des armatures, de réduire les temps de calcul, d'améliorer la méthode de régularisation et de prendre en compte les déformations permanentes.
4
Yao, Lan. "Experimental and numerical study of dynamic crack propagation in ice under impact loading". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI043/document.
Texto completoResumen
Les phénomènes liés au comportement à la rupture de la glace sous impact sont fréquents dans le génie civil, pour les structures offshore, et les processus de dégivrage. Pour réduire les dommages causés par l'impact de la glace et optimiser la conception des structures ou des machines, l'étude sur le comportement à la rupture dynamique de la glace sous impact est nécessaire. Ces travaux de thèse portent donc sur la propagation dynamique des fissures dans la glace sous impact. Une série d'expériences d'impact est réalisée avec un dispositif de barres de Hopkinson. La température est contrôlée par une chambre de refroidissement. Le processus dynamique de la rupture de la glace est enregistré avec une caméra à grande vitesse et ensuite analysé par des méthodes d'analyse d'images. La méthode des éléments finis étendus complète cette analyse pour évaluer la ténacité dynamique. Au premier abord, le comportement dynamique de la glace sous impact est étudié avec des échantillons cylindriques afin d'établir la relation contrainte-déformation dynamique qui sera utilisée dans les simulations numériques plus tard. Nous avons observé de multi-fissuration dans les expériences sur les échantillons cylindriques mais son étude est trop difficile à mener. Pour mieux comprendre la propagation des fissures dans la glace, des échantillons rectangulaires avec une pré-fissure sont employés. En ajustant la vitesse d'impact on aboutit à la rupture des spécimens avec une fissure principale à partir de la pré-fissure. L'histoire de la propagation de fissure et de sa vitesse sont évaluées par analyse d'images basée sur les niveaux de gris et par corrélation d'images. La vitesse de propagation de la fissure principale est identifiée dans la plage de 450 à 610 m/s ce qui confirme les résultats précédents. Elle varie légèrement au cours de la propagation, dans un premier temps elle augmente et se maintient constante ensuite et diminue à la fin. Les paramètres obtenus expérimentalement, tels que la vitesse d'impact et la vitesse de propagation de fissure, sont utilisés pour la simulation avec la méthode des éléments finis étendus. La ténacité d'initiation dynamique et la ténacité dynamique en propagation de fissure sont déterminées lorsque la simulation correspond aux expériences. Les résultats indiquent que la ténacité dynamique en propagation de fissure est linéaire vis à vis de la vitesse de propagation et semble indépendante de la température dans l'intervalle -15 à -1 degrésThe phenomena relating to the fracture behaviour of ice under impact loading are common in civil engineering, for offshore structures, and de-ice processes. To reduce the damage caused by ice impact and to optimize the design of structures or machines, the investigation on the dynamic fracture behaviour of ice under impact loading is needed. This work focuses on the dynamic crack propagation in ice under impact loading. A series of impact experiments is conducted with the Split Hopkinson Pressure Bar. The temperature is controlled by a cooling chamber. The dynamic process of the ice fracture is recorded with a high speed camera and then analysed by image methods. The extended finite element method is complementary to evaluate dynamic fracture toughness at the onset and during the propagation. The dynamic behaviour of ice under impact loading is firstly investigated with cylindrical specimen in order to obtain the dynamic stress-strain relation which will be used in later simulation. We observed multiple cracks in the experiments on the cylindrical specimens but their study is too complicated. To better understand the crack propagation in ice, a rectangular specimen with a pre-crack is employed. By controlling the impact velocity, the specimen fractures with a main crack starting from the pre-crack. The crack propagation history and velocity are evaluated by image analysis based on grey-scale and digital image correlation. The main crack propagation velocity is identified in the range of 450 to 610 m/s which confirms the previous results. It slightly varies during the propagation, first increases and keeps constant and then decreases. The experimentally obtained parameters, such as impact velocity and crack propagation velocity, are used for simulations with the extended finite element method. The dynamic crack initiation toughness and dynamic crack growth toughness are determined when the simulation fits the experiments. The results indicate that the dynamic crack growth toughness is linearly associated with crack propagation velocity and seems temperature independent in the range -15 to -1 degrees
5
Goldspiegel, Fabien. "Simulation numérique du procédé de clouage grande-vitesse pour l'assemblage de matériaux hybrides". Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEM028/document.
Texto completoResumen
L’industrie automobile suit une politique d’allègement via l’introduction de matériaux plus légers et plus diversifiés dans la structure du véhicule. Parmi les techniques d’assemblages envisagées, le présent document se focalise sur le procédé de clouage grandevitesse. Des essais d’assemblages ont été réalisés en laboratoire sur de l’aluminium de fonderie, de l’acier DP780 et DP1180. La cinématique d’assemblage, les modes de ruptures, la réaction des tôles et les propriétés de la liaison sont étudiés. Des modèles matériaux ont été choisis pour rendre compte des phénomènes dynamiques et de rupture des tôles pendant l’assemblage. Le clou et les tôles ont ensuite été caractérisés mécaniquement dans plusieurs conditions de chargements et utilisés pour la calibration des modèles. Un modèle par éléments finis du clouage est crée; ses sensibilitées aux variations de maillage, frottement et modèle matériau sont évaluées et ses limitations capturées, soit par une pression d’assemblage inadaptées soit par la fragilité du clou. Des simulations de traction-croix et traction-cisaillement permettent finalement l’estimation des propriétés mécaniques de la liaisonLightweigthing structures using mixed material components have become one of the main target of automotive industry’s future. Among the joining processes under exploration, the present work focuses on High-Speed Nailing. Experimental campaigns are conducted under laboratory conditions on layers superposition made of cast aluminium, dual-phase steels DP780 and DP1180. Joining kinematics, sheets fracture modes, reaction the nail insertion and nailed-joint strengths are investigated in various conditions of experiment. Material models are chosen to account for the dynamic and fracture phenomena exhibit by materials in the joining stage. Mechanical tests are performed on nail and sheets materials under different strain-rates and stress-states and used as references for the calibration procedure. A finite element model of the joining stage is built; its sensitivity to mesh size, friction and material formulation is evaluated and its limitations captured by either inappropriate joining pressure setting or nail brittleness. After a new equilibrium is reached, the nailed-joint is tested through cross-tension and sheartension simulations to tackle the prediction of in-service properties
6
Jiang, Jinlin. "Mechanical control on fluid-induced aseismic slip : insights from injection experiment modeling". Electronic Thesis or Diss., Université Paris sciences et lettres, 2023. http://www.theses.fr/2023UPSLM056.
Texto completoResumen
Les injections de fluides liées à l’exploitation de réservoirs géothermiques entraînent bien souvent la réactivation de failles, sous la forme d’un glissement lent ou asismique, déclenchant à son tour des séismes dits induits. Cette thèse est consacrée à une étude numérique du glissement asismique déclenché par injection de fluide. Un modèle FEM y est développé afin de simuler des expériences d’injection effectuées en presse triaxiale. Les simulations présentées dans ce travail permettent de quantifier l’effet du scenario d’injection, de la diffusivité de la faille, des propriétés de frottement et de l’état de contrainte initial sur la dynamique d’expansion du glissement asismique, fournissant un nouveau regard sur les lois d’échelles caractérisant la vitesse de rupture et le moment maximum libéré. L’approche présentée permet de fournir des pistes de réflexion pour améliorer l’évaluation de l’aléa lié à l’exploitation géothermique. Le modèle numérique développé est également validé sur un jeu de données expérimentales, ce qui ouvre des perspectives importantes pour approfondir l’interprétation mécanique des expériences d’injection menées en laboratoireFluid injections performed in the framework of geothermal exploitation can reactivate slip on preexisting crustal faults, leading to aseismic slip transients in turn triggering so-called triggered earthquakes. This PhD thesis is a numerical study dedicated to the physical control on the fluid-induced aseismic slip. A hydromechanical FEM is developed to simulate injection experiments performed in a tri-axial cell in the laboratory. The simulations presented allow to quantify the effect of the injection scenario, the hydraulic diffusivity, the fault friction and pre-stress on the dynamics of induced aseismic slip, providing new insights into the scaling laws commonly used to characterize this phenomenon, in particular the rupture speed and the maximum moment released. The approach presented here is thus of importance in the perspective of improving hazard mitigation in the context of geothermal exploitation. The model predictions are also validated on a real experimental dataset, which opens a new avenue to improve the mechanical interpretation of injection experiments in the laboratory
7
Mahelle, Pierre. "Caractérisation expérimentale et numérique du comportement d'assemblages soudés soumis à des sollicitations quasi-statiques et dynamiques". Valenciennes, 2007. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/f32d6052-7ffa-4abc-8874-e306547dd985.
Texto completoResumen
Les observations faites sur des structures métalliques soumises au crash ou à l’impact mettent en évidence deux catégories de rupture : la rupture initiée en pleine tôle, et la rupture localisée au niveau des zones d’assemblage. Il est donc important de pouvoir prédire le comportement des liaisons pour éviter qu’elles ne rompent et entraînent une désarticulation structurale complète et particulièrement brutale. Les objectifs des travaux menés sont de mesurer la réponse d’un assemblage soudé par point lorsqu’il est sollicité en quasi-statique et en dynamique, de déterminer quelle est l’influence de la vitesse de sollicitation sur son comportement et de comprendre comment et où la rupture s’initie et se propage dans cet assemblage. Un nouveau type d’essai a permis de caractériser la liaison soudée pour des sollicitations de traction, cisaillement et en modes mixtes. Les assemblages sont testés en quasi-statique et en dynamique pour des vitesses comprises entre 5 mm/min et 1m/s. Un montage permettant de solliciter le point soudé en traction indirecte aux barres de Hopkinson a été développé. Ce montage permet de solliciter l’assemblage soudé pour des vitesses de traction de l’ordre de 13 m/s. Une analyse des faciès, des modes de rupture et des observables globales est réalisée. Pour compléter l’approché expérimentale un modèle numérique E. F. Volumique de l’assemblage à l’échelle mésoscopique est réalisé. Les propriétés élasto-visco-plastiques de quatre zones remarquables de la Z. A. T. Sont identifiées sur des éprouvettes affectées thermiquement. Ce modèle permet d’appréhender les mécanismes locaux de déformation de la soudure sous diverses sollicitations mécaniquesWhen subjecting a metallic structure to an impact or a crash, two kinds of fracture can be seen to appear jointly: rupture initiated in the sheet and rupture located on the joint areas. Depending on the type of transportation mean and materials used for the design of the vehicles, structures can be assembled either by rivets, spotwelds or weld beads. To prevent the failure of these joints, which can lead to a complete and particularly brutal structural disarticulation, their behaviour must be studied. The aims of this work are to measure the response of a spotwelded joint under quasi-static and dynamic loadings, to determine the load velocity influence on its behaviour, to understand how and where the failure starts and propagates in the assembly. Original tests, which make it possible to mix loading directions and to control the boundary conditions around the spotweld and the deformation of the metal sheet, were developed and performed under quasi-static and dynamic loadings on an hydraulic jack in a range of velocities from 5mm/mn to 1m/s. A new device was also developed to test spotwelds in pure tensile direction on SHB. This device uses SHB in a no-direct tensile testing configuration and a velocity of 13 m/s is reached. Load-displacement responses, failure mechanisms and topographies were obtained. To complete experiments, a fine numerical model of the spotweld was performed. The elastoplastic properties of the HAZ were experimentaly identified using some materials having undergone heat treatments. This model allows us to understand where the deformations are located
8
Solignac, Marie-Paul. "Etude du comportement a la fissuration en fluage et en fatigue d'aciers inoxydables austenitiques z2 cnd 17-12 (316 l) a 550 c". Paris 6, 1986. http://www.theses.fr/1986PA066540.
Texto completoResumen
Description du comportement du materiau en fluage par une loi puissance. Etude des relations entre la vitesse de propagation et les parametres mecaniques. Prevision de la duree de vie. En fatigue, etude de l'influence des parametres experimentaux et de certains traitements (vieillissement, ecrouissage) sur la fissuration. Etude par microscopie electronique des modes de rupture, ainsi que de la microstructure necessaire a la comprehension du comportement de l'acier
9
LIU, ZENG-GANG. "Comportement et modelisation des materiaux composites carbone/epoxyde en cisaillement a grande vitesse". Nantes, 1987. http://www.theses.fr/1987NANT2011.
Texto completo
10
Bacchi, Renato Vieira. "Análise das imagens de ruptura de corpos de prova de polipropileno em ensaio de tração obtidas através de câmera de alta velocidade". Master's thesis, [s.n.], 2011. http://hdl.handle.net/10362/50540.
Texto completoResumen
Orientadores: Edvaldo Sabadini, Marco-Aurelio De PaoliDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
Made available in DSpace on 2018-08-19T06:55:08Z (GMT). No. of bitstreams: 1 Bacchi_RenatoVieira_M.pdf: 13069240 bytes, checksum: 33b4fb8f5e4184296681a0de7210799c (MD5) Previous issue date: 2011
Resumo: Peças de polipropileno isotático, iPP, moldadas por injeção podem apresentar variação de propriedades em função dos parâmetros de injeção. Uma dessas propriedades é a propagação de ruptura, que foi estudada neste trabalho com o uso de imagens obtidas com câmera de alta velocidade ajustada para velocidades de captura entre 18.000 e 45.000 fotos por segundo. Os parâmetros modificados no processo de moldagem por injeção foram o tempo de resfriamento e a temperatura do molde. Foram formados seis grupos de corpos de prova (CP) a serem submetidos aos ensaios de tração. As imagens dos rompimentos nos ensaios de tração foram capturadas com a câmera de alta velocidade. Os CP dos grupos 1, 2 e 3 foram resfriados em molde a 22 °C durante 8, 25 e 55 s, respectivamente. Os CP dos grupos 4, 5 e 6 foram resfriados em molde a 80 °C por 8, 25 e 55 s, respectivamente. Foram observados três padrões de rompimento associados aos diferentes grupos. O primeiro padrão correspondente aos CP dos grupos 1 e 4, com tempos de ruptura entre 0,04 e 0,09 ms. O segundo padrão, apresentado pelos grupos 2 e 3, apresenta formação de pescoço e alto alongamento, porém sem tempo de ruptura definido. O terceiro padrão, observado nos grupos 5 e 6, apresenta ruptura com tempo de propagação médio de 1,5 ms e propagação elipsóide da fissura. Foram realizadas medidas de difração de raios-X e calorimetria diferencial exploratória, mas não foram observadas variações significativas dos graus de cristalinidade para os diferentes grupos. Foram obtidas micrografias por microscopia eletrônica de varredura para amostras dos seis grupos, que mostraram maior uniformidade na superfície de ruptura para os grupos 1 e 4. Para os grupos 2 e 3 foi observada presença de fibrilas. Para os grupos 5 e 6 foram observadas diferenças significativas entre as superfícies do centro do e das extremidades do CP. Para observar os efeitos do envelhecimento nos padrões de ruptura, foram armazenados alguns CP de cada um dos grupos durante 12 semanas. O enrijecimento do material tende a causar ruptura mais rápida em todos os grupos e os grupos 2 e 3 foram os mais afetados. Os resultados deste trabalho mostram que, não apenas as propriedades mecânicas do iPP são afetadas pelas variáveis na moldagem por injeção como também os mecanismos de rompimento variam consideravelmente, e estes são claramente observados com imagens em alta velocidade
Abstract: Injection-molded isotactic polypropylene, iPP, samples present different properties variation as a function of the injection parameters. One of these properties is the rupture propagation on the material, which was studied with the use a high-speed camera adjusted to capture from 18,000 to 45,000 frames per second. The injection molding parameters modified were: cooling time and temperature of the mold. Six groups of specimens were molded and submitted to tensile tests until failure. The rupture images were capture with the high-speed camera. The specimens of the groups 1, 2 and 3 were cooled in the mold at 22 °C during 8, 25 and 55 seconds, respectively. Groups 4, 5 and 6 were cooled in the mold at 80 °C during 8, 25 and 55 s, respectively. Three major rupture patterns associated with the groups were observed. The first pattern, presented by groups 1 and 4, consists in a rapid rupture, with time of propagation between 0.04 and 0.09 ms. A second pattern, observed in groups 2 and 3, presents necking and high elongation, but without a precise time for complete rupture. The third pattern, observed for groups 5 and 6, shows an ellipsoid crack propagation, with an average time for rupture of 1.5 ms. X-Ray diffraction and differential scanning calorimetry measurements were made, but no considerable differences in the degree of crystallinity among the groups was observed. Scanning electron microscopy images of the rupture surface of the specimens showed that there is considerable uniformity in groups 1 and 4. In groups 2 and 3 the appearance of fibrils was observed, whilst for groups 5 and 6 considerable differences between the skin and the core of the specimen was observed. Physical ageing effects on the rupture patterns were studied after the storage of few specimens during 12 weeks. Hardening of the material, due to physical ageing, affected all the groups, but it was most apparent in groups 2 and 3, which started to behave more like the other groups after this time. The result in this work showed that not only the mechanical properties of iPP are affected by the modification in the mold injection parameters, but also the rupture mechanisms can considerably vary. This is observed clearly in the high-speed images
Mestrado
Físico-Química
Mestre em Química
Libros sobre el tema "Rupture Speed"
1
Drury, Joseph. The Speed of Tristram Shandy. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198792383.003.0005.
Texto completoResumen
The expansion of the turnpike system and the introduction of steel springs to carriages in the mid-eighteenth century led to a sudden increase in the speed at which people, goods, and information could travel around Britain. Some celebrated the profits and pleasures afforded by this new culture of mobility. Others, including Rousseau, warned that technological improvement was not being matched by comparable advances in health, happiness, and virtue. This chapter reads the radical digressiveness of Laurence Sterne’s Tristram Shandy as a response to the alienating moral effects of the conventional modern novel’s linear, end-oriented narrative machinery. By derailing narrative progress—a rupture signalled in volume VII by the shattering of Tristram’s post-chaise—and withholding closure altogether, Sterne sought to deliver his readers from the circuit of desire, frustration, and disappointment he understood to organize both the experience of reading a modern novel and living in a modern technological society.
Capítulos de libros sobre el tema "Rupture Speed"
1
Cooper, Marcia A., Michelle N. Skaggs y Phillip L. Reu. "High-Speed Stereomicroscope Digital Image Correlation of Rupture Disc Behavior". En Advancement of Optical Methods in Experimental Mechanics, Volume 3, 19–26. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-22446-6_3.
Texto completo
2
Lo Conte, Antonietta, Giuseppe Bucca y Andrea Collina. "Simulation of the Rupture of the Contact Wire of a High speed Catenary". En Lecture Notes in Civil Engineering, 172–82. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-39109-5_18.
Texto completo
3
Li, Yunxiang, Lu Meng, Song Li, Bo Liu, Disi Wang, Youpeng Zhang, Lu Zhang y Wei Jiang. "Study on the Effects from Spacer Wires on Coolant Flow Within a Fuel Assembly Used in the CiADS Core". En Springer Proceedings in Physics, 29–44. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-1023-6_4.
Texto completoResumen
AbstractSpacer wires are frequently applied as the positioning components of fuel bundles in lead-based fast reactor fuel assemblies. It is extremely important to carry out the research of the impacts from spacer wires on coolant flow within fuel assemblies, and therefore the safety performances of reactor core. In this paper, the open source CFD calculation software OpenFOAM was adopted to perform the refined numerical simulation on the multi-pitch assembly model of 61 bundles and analyze the distribution of flow characteristics such as pressure, velocity, and temperature. The results show that: there is a pressure difference on both sides of the wires, which may cause the coolant to mix laterally; the mixing effect incurred by the wires may cause the uneven distribution of coolant velocity. There are obvious high-speed and low-speed zones, and the high-speed zone is located at the same position as the low-pressure zone. Due to the high flow rate in the peripheral sub-channel, the coolant temperature is lower. The maximum temperature difference at the outlet of the fuel assembly can reach 20K, which may cause local overheating and therefore cladding rupture under accidental conditions. The simulation can provide a reference for the correction of the calculation results of the 1D single-channel program and lay the foundation for the development of the subsequent two-phase flow model for fuel assemblies containing wire spacers.
4
Sachs, Jonathan. "Coleridge’s Rome". En The Call of Classical Literature in the Romantic Age, 267–88. Edinburgh University Press, 2017. http://dx.doi.org/10.3366/edinburgh/9781474429641.003.0011.
Texto completoResumen
Coleridge’s comparison between Napoleonic France and imperial Rome seeks to understand “revolutionary time,” that ostensibly new sense of time considered as a product of the French Revolution that sees the future as freed from past precedent. In the context of this seeming rupture between past and present, Coleridge associates the Roman transition from republic to empire with a particular pace and rate of change, and with slowness generally, a slowness that serves as a marked contrast to the apparent speed of his present moment. This chapter shows how Coleridge’s slow time is inextricable from the seeming speed and acceleration with which events were understood to develop in the aftermath of the French Revolution, in modernity. Coleridge returns processes of slow and gradual change into the French Revolution’s seeming rupture with the past.
5
Herzog, Tyler L., Bryan T. Kelly y Diana J. Kelm. "A 51-Year-Old Man With Fever, Dyspnea, and Productive Cough". En Mayo Clinic Case Review for Pulmonary and Critical Care Boards, editado por Cassandra M. Braun y Hemang Yadav, 75–84. Oxford University PressNew York, 2023. http://dx.doi.org/10.1093/med/9780197755877.003.0010.
Texto completoResumen
Abstract Pneumomediastinum and pneumoperitoneum are rare pulmonary disorders. They can occur spontaneously or result from medical treatment (iatrogenic causes), underlying disorders, or trauma. In patients receiving ventilation, pneumomediastinum and pneumoperitoneum result from barotrauma and alveolar rupture. Currently, no guidelines exist to guide evaluation and management of either disorder. Most patients present with mild, self-limited disease that resolves with conservative treatment. Administration of high concentrations of oxygen may help speed resorption of the free air. An underlying cause should be sought and treated as necessary. Rarely, patients may have a more serious complication, such as tension pneumomediastinum or abdominal compartment syndrome, that necessitates emergent treatment with decompression.
6
Zakraysek, Louis. "RUPTURE TESTING FOR THE QUALITY CONTROL OF ELECTRODEPOSITED COPPER INTERCONNECTIONS IN HIGH-SPEED, HIGH-DENSITY CIRCUITS". En Electronics Reliability and Measurement Technology, 89–106. Elsevier, 1988. http://dx.doi.org/10.1016/b978-081551171-7.50013-5.
Texto completo
7
Guirao, Fernando. "The Decision to Grant the Preference (1964–1967)". En The European Rescue of the Franco Regime, 1950-1975, 170–234. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198861232.003.0005.
Texto completoResumen
For the Six, Chapter 4 shows, the Spanish question boiled down to whether they would grant the preference rather than how. Documentary records and trade data show that the EEC did not discriminate against Spanish products. The EEC’s policy on Franco Spain was forged around the justification that relations with dictatorships of less-developed countries served to promote economic development and social change. These changes would naturally lead to a collective desire for political change. France and West Germany acted accordingly and exercised due influence on their peers. In the pursuit of their own interests, the European Community and its member-states opted to induce progressive reform towards West-European institutional standards over punishment or rupture. The political debate was limited to the speed of such changes, not to the validity of the assumption. The Europeanization/democratization binomial implied that closer relations with the EEC would promote convergence towards West-European standards, including democratization.
8
Bunker, Bruce C. y William H. Casey. "Stress Corrosion Cracking: Chemically Activated Nanomechanics". En The Aqueous Chemistry of Oxides. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780199384259.003.0024.
Texto completoResumen
Although dissolution reactions involving water can etch and decompose oxides, truly catastrophic failures of oxide structures usually involve fractures and mechanical failures. Geologists and geochemists have long recognized that water and ice both play key roles in promoting the fracture and crumbling of rock (see Chapter 17). Freezing and thawing create stresses that amplify the rate at which water attacks metal–oxygen bonds at the crack tip. The interplay between water and stressed oxides also leads to common failures in man-made objects, ranging from the growth of cracks from flaws in windshields to the rupture of optical fibers in communication systems. In this chapter, we outline how mechanical deformations change the reactivity of metal–oxygen bonds with respect to water and other chemicals, and how reactions on strained model compounds have been used to predict time to failure as a function of applied stress. The basic phenomenon of stress corrosion cracking is illustrated in Figure 16.1. Cracks can propagate through oxide materials at extremely fast rates, as anyone who has dropped a wine glass on the floor can attest. High-speed photography reveals that when glass shatters, cracks can spread at speeds of hundreds of meters per second, or half the speed of sound in the glass. At the other end of the spectrum, cracks in glass can grow from preexisting flaws so slowly that only a few chemical bonds are broken at the crack tip per hour. Because mechanical failures are associated with cracking, it is critical for design engineers to understand the factors that control crack growth rates for this enormous range of crack velocities (a factor of 1012). In addition, because it is difficult to measure crack velocities slower than 10−8 m/second, it is often necessary to make major extrapolations from measured data to predict the long-term reliability of glass and ceramic objects. Will an optical fiber under stress fail in 1 year or 10 years? Answering this question can require accurate extrapolations down to crack growth rates as low as 10−10 m/second.
9
Chen, L., N. Zhang y Q. Jia. "Equivalent linear analysis of high-speed railway seismic-isolated bridge subjected to forward rupture directivity type near-faul ground motions". En Bridge Maintenance, Safety, Management and Life Extension, 1588–95. CRC Press, 2014. http://dx.doi.org/10.1201/b17063-243.
Texto completo
10
Mespoulet, Jérôme y Pierre Louis Hereil. "An Overview of Theoretical and Experimental Techniques for Material Behavior Characterization in Shock Physics". En Critical Energy Infrastructure Protection. IOS Press, 2022. http://dx.doi.org/10.3233/nicsp220005.
Texto completoResumen
Shock Physics that deals with material behavior at a very high strain rate (in the order of material propagation speed) reveals more and more its importance in engineering applications (automotive, defense, aeronautic, space, energy, etc.), geophysics (earth’s behavior, asteroid impacts) or astrophysics (planets and stars behavior). Nowadays, this term is used more often when classical high-speed dynamics reach their physical limits. After a short introduction to shock physics, an application to lightweight armor is used to illustrate the importance of coupling tuned experiments with simulations for dynamic material studies: In fact, lightweight armors of soldiers are in constant evolution to optimize protection efficiency. In this area, more and more complex simulations are investigated with compound structures including polymeric foam, composite, metal, and ceramic. Even if numerical capabilities are in perpetual evolution, there is a constant need of improving the knowledge of individual material response in the strain, strain rate regime closed to the threat. Collecting parameters for Equation Of State (EOS), strength and/or rupture models to fit material models is thus mandatory to ensure reliable numerical investigations. Since 2015, THIOT INGENIERIE Shock Physics Laboratory has been selected by the French Ministry Of Defense (MOD) Land Systems to perform materials characterization in three main families of ballistic materials. Parallel to those tasks, in-house simulations done by the dynamic material department have shown a very good agreement with validation tests based on the dynamic material characterizations. A coupled approach between laboratory experiments and numerical simulations has shown its relevance with ceramic, [1], an Ultra High Molecular Weight Polyethylene composite (UHMWPE) [2] and a polymeric foam [3]. For all those materials, the BBA methodology has been used to calibrate EOS, strength, and damage models by conducting a step-by-step procedure with a dual approach, mixing together experimental tests and numerical works simultaneously.
Actas de conferencias sobre el tema "Rupture Speed"
1
Sun, Chuanjiao, Jie Zhang y Xiaojing Ban. "Vehicle Speed Determination Based on Front Windshield Glass Rupture Area". En Ninth Asia Pacific Transportation Development Conference. Reston, VA: American Society of Civil Engineers, 2012. http://dx.doi.org/10.1061/9780784412299.0039.
Texto completo
2
Geng, Jihui y Kelly Thomas. "Evaluation of Blast Loads From Pipe Ruptures". En ASME 2017 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/pvp2017-65186.
Texto completoResumen
High-pressure pipeline ruptures are a credible explosion hazard at many industrial facilities. The blast field generated by a pipe rupture is highly directional. However, there have been few evaluations of the directional blast loads produced by pipe ruptures. This paper addresses the blast loads generated by a typical “fish mouth” type pipe rupture. The effects of five key parameters on the resulting directional blast field were examined: rupture opening speed, final rupture opening area, pipe diameter, initial gas pressure, and initial gas temperature. The resultant blast loads were compared to those based on existing blast curves for Pressure Vessel Bursts (PVB), the most common of which is based on an assumption of a spherical vessel geometry and instantaneous failure of the entire pressure vessel boundary. The effective gas volume (i.e., number of pipe diameters) required to achieve reasonable agreement between the blast load based on existing PVB blast curves and that resulting from a high-pressure pipeline fish mouth rupture for a specified direction was determined.
3
Sun Chuanjiao, Zhang Jie y Ban Xiaojing. "Vehicle Speed Determination Based on the Front Windshield Glass Rupture Area". En 2013 Fifth International Conference on Measuring Technology and Mechatronics Automation (ICMTMA 2013). IEEE, 2013. http://dx.doi.org/10.1109/icmtma.2013.318.
Texto completo
4
Lykotrafitis, G. y A. J. Rosakis. "Sliding of Frictionally Held Incoherent Interfaces Under Dynamic Shear Loading". En ASME/STLE 2004 International Joint Tribology Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/trib2004-64374.
Texto completoResumen
An experimental investigation was conducted to study the nature of dynamic rupture caused by shear loading, through impact, of interfaces which are held together by friction under external pressure. The dynamic stress field developed during rupture propagation was recorded in real time by a high-speed camera in conjunction with a classical dynamic photoelasticity set-up. Visual evidences of different dynamic propagating rupture modes were recorded. Unlike classical shear cracks in coherent interfaces of finite strength, rupture in frictional interfaces seems to grow without noticeable acceleration phases and at various discreet speeds. At low impact velocities a crack-like rupture mode occurs which becomes super-shear with the increase of the impact speed and a shear Mach cone emanates from the rupture point. For higher impact speeds super-shear and super-sonic Mach lines are observed formatting an unstable slip pulse which subsequently vanishes whereas evidences for extended stick and slip regions are recorded. Increasing the external applied pressure the observed features are intensified.
5
Aryafar, H. y H. P. Kavehpour. "Rupture Process During Drop Coalescence". En ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81841.
Texto completoResumen
During the coalescence of a drop with a planar interface, a hole is generated in a microscopic film that separates the drop from the interface. An experimental study has been performed to investigate the time dependent behavior of the radius of the hole generated during coalescence. The study consisted of placing drops of various sizes and physical properties on a planar interface. The coalescence process was recorded from underneath the interface with the aid of a high speed digital camera and a prism. The experiment captured two separate processes, film rupture and the closing of the hole. During the film rupture, the hole radius demonstrated a power law time dependence. Dimensional analysis showed the percentage of time the hole used to reach its maximum radius was approximately constant for all drops. Moreover, all dimensionless drop rupture radii and times fit onto a single master curve and were independent of their physical properties during the opening. However during the closing of the hole, the dimensionless time and radii did not fit a master curve analogous to the hole rupture. The closing of the hole is an entirely different event from the opening and is governed by different parameters.
6
Godbole, Ajit, Guillaume Michal, Cheng Lu, Philip Venton y Philip Colvin. "Full-Bore Pipeline Rupture as ‘Transient Fanno’ Flow". En 2016 11th International Pipeline Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ipc2016-64334.
Texto completoResumen
Full-bore decompression of an initially highly pressurized pipe has been studied extensively in recent years. The main aim of this effort has been to estimate the speed of the decompression wave and its relationship to the speed of a travelling fracture in the pipe wall. It has been demonstrated that the speed of the decompression wave is influenced by the friction at the gas-solid interface, and also by the pipe size (diameter). The numerical value of the friction factor has been traditionally estimated using known relationships such as the Haaland formula. However, it has also been noticed that the friction factor calculated in this way has to be increased many-fold to achieve agreement between theory and experiment. To date, there is no physical justification for this increase. The present paper proposes an explanation by modelling the full-bore decompression as a ‘transient Fanno’ flow. The model development is based on the observation that the flow at the exit plane always tends to approach a ‘choked’ condition (sonic velocity). It is shown that a re-interpretation of the Fanno flow formula allows an estimation of the irreversibility, and therefore the friction factor, in the evolving flow. When averaged over space and time, the friction factor attains a value that need not be artificially adjusted. This value of the friction factor can be used in one-dimensional models of the decompression process. Also, the role of the ‘second coefficient of viscosity’ during the initial instants of the highly transient flow is examined.
7
Botros, K. K., J. Geerligs y R. J. Eiber. "Decompression Wave Speed in Rich Gas Mixtures at High Pressures (37 MPa) and Implications on Fracture Control Toughness Requirements in Pipeline Design". En 2010 8th International Pipeline Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ipc2010-31027.
Texto completoResumen
Measurements of decompression wave speed in conventional and rich natural gas mixtures following rupture of a high-pressure pipe have been conducted. A high pressure stainless steel rupture tube (internal diameter = 38.1 mm, and 42 m long), has been constructed and instrumented with 16 high frequency-response pressure transducers mounted very close to the rupture end and along the length of the tube to capture the pressure-time traces of the decompression wave. Tests were conducted for initial pressures of 33–37 MPa-a and a temperature range of 21 to 68 °C. The experimentally determined decompression wave speeds were compared to both GASDECOM and PIPEDECOM predictions with and without non-equilibrium condensation delays at phase crossing. The interception points of the isentropes representing the decompression process with the corresponding phase envelope of each mixture were correlated to the respective plateaus observed in the decompression wave speed profiles. Additionally, speeds of sound in the undisturbed gas mixtures at the initial pressures and temperatures were compared to predictions by five equations of state, namely BWRS, AGA-8, Peng-Robinson, Soave-Redlich-Kwong, and GERG. The measured gas decompression curves were used to predict the fracture arrest toughness needed to assure fracture control in natural gas pipelines. The rupture tube test results have shown that the Charpy fracture arrest values predicted using GASEDCOM are within +7 (conservative) and −11% (non-conservative) of the rupture tube predicted values. Similarly, PIPEDECOM with no temperature delay provides fracture arrest values that are within +13 and −20% of the rupture tube predicted values, while PIPEDECOM with a 1 °C temperature delay provides fracture arrest values that are within 0 and −20% of the rupture tube predicted values. Ideally, it would be better if the predicted values by the equations of state were above the rupture tube predicted values to make the predictions conservative but that was not always the case.
8
Cosham, Andrew, David G. Jones, Keith Armstrong, Daniel Allason y Julian Barnett. "Ruptures in Gas Pipelines, Liquid Pipelines and Dense Phase Carbon Dioxide Pipelines". En 2012 9th International Pipeline Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ipc2012-90463.
Texto completoResumen
Ruptures in gas and liquid pipelines are different. A rupture in a gas pipeline is typically long and wide. A rupture in a liquid pipeline is typically short and narrow, i.e. a slit or ‘fish-mouth’ opening. The decompression of liquid (or dense) phase carbon dioxide (CO2) immediately after a rupture is characterised by a rapid decompression through the liquid phase, and then a long plateau. At the same initial conditions (pressure and temperature), the initial speed of sound in dense phase CO2 is greater than that of natural gas and less than half that of water. Consequently, the initial decompression is more rapid than that of natural gas, but less rapid than that of water. A question then arises … Does a rupture in a liquid (or dense) phase CO2 pipeline behave like a rupture in a liquid pipeline or a gas pipeline? It may exhibit behaviour somewhere in-between the two. A ‘short’ defect that would rupture at the initial pressure might result in a short, narrow rupture (as in a liquid pipeline). A ‘long’ defect that would rupture at the (lower) saturation pressure might result in a long, wide rupture (as in a gas pipeline). This is important, because a rupture must be long and wide if it is to have the potential to transform into a running fracture. Three full-scale fracture propagation tests (albeit shorter tests than a typical full-scale test) published in the 1980s demonstrate that it is possible to initiate a running ductile fracture in a CO2 pipeline. However, these tests were on relatively small diameter, thin-wall line pipe with a (relatively) low toughness. The results are not applicable to large diameter, thick-wall line pipe with a high toughness. Therefore, in advance of its full-scale fracture propagation test using a dense phase CO2-rich mixture and 914×25.4 mm, Grade L450 line pipe, National Grid has conducted three ‘West Jefferson Tests’. The tests were designed to investigate if it was indeed possible to create a long, wide rupture in modern, high toughness line pipe steels using a dense phase CO2-rich mixture. Two tests were conducted with 100 mol.% CO2, and one with a CO2-rich binary mixture. Two of the ‘West Jefferson Tests’ resulted in short ruptures, similar to ruptures in liquid pipelines. One test resulted in a long, wide rupture, similar to a rupture in a gas pipeline. The three tests and the results are described. The reasons for the different behaviour observed in each test are explained. It is concluded that a long, wide rupture can be created in large diameter, thick-wall line pipe with a high toughness if the saturation pressure is high enough and the initial defect is long.
9
Ajaev, Vladimir S. "Simulations of Rupture in Thin Films of Evaporating Liquids". En ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-80920.
Texto completoResumen
Evolution of dry patches in a thin film of a volatile liquid on a uniformly heated plate is investigated in the framework of a lubrication-type model. The effects of surface tension, evaporation, thermocapillarity, and disjoining pressure are taken into account. Dry areas on the plate are modeled by isothermal microscopic films, which are in thermodynamic equilibrium with the vapor. For non-polar liquids such equilibrium is achieved due to van der Waals forces. Simulations indicate formation of a well-defined capillary ridge around a growing dry patch and show increase in the contact line speed with time. For polar liquids the microscopic film is formed by combined action of van der Waals and electrical double layer forces, the capillary ridge is very small and the contact line speed quickly approaches a constant value. Numerical simulations demonstrate that the proposed model is capable of describing a number of complicated phenomena observed in dewetting of evaporating films.
10
Xia, Kaiwen, Ares J. Rosakis y Hiroo Kanamori. "Spontaneous Rupturing Along a Frictional Interface". En ASME/STLE 2004 International Joint Tribology Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/trib2004-64354.
Texto completoResumen
We designed a laboratory model to investigate the spontaneous rupturing along a frictionally held interface. A frictional contact, which mimics a material interface or geological fault, is simulated using two photoelastic plastics plates (Homalite or Polycarbonate) held together by friction and compression. The pre-uniaxial static loading is exerted by a hydraulic press. A unique design used in our experiments, which starts the spontaneous rupturing, is the exploding wire technique. It triggers the rupture within a controlled environment while keeping the spontaneous nature of the rupturing. The fault is oblique to the compression axis to provide the shear driving force for continued rupturing. We performed the spontaneous repturing experiment along an interface between both similar and dissimilar materials. Under proper loading conditions, a shear rupture which initially propagates at Rayleigh wave speed, jumps to a supershear speed (close to the longitudinal wave speed) after propagating a finite distance L in a similar material system. For the dissimilar material system, directionality of rupture propagation is observed. A rupture propagating at the generalized Rayleigh wave speed is observed in the same direction as the sliding of the more compliant material and in the opposite direction, supershear rupture is possible under proper loading condition.
Informes sobre el tema "Rupture Speed"
1
Botros, Kamal. PR-383-104506-R02 Shock Tube Measurement of Decompression Wave Speed in CO2 with Impurities. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), marzo de 2013. http://dx.doi.org/10.55274/r0010811.
Texto completoResumen
This report contains the results of 43 shock tube tests simulating pipeline rupture using an NPS 2 (DN50) shock tube with a rupture disc. These tests were conducted on pure CO2, binaries with N2, O2, CO, CH4 and H2, as well as for compositions representative of typical carbon capture technologies. The resulting decompression wave speeds are compared with predictions utilizing different equations of state.
2
Utsumi, Yukihiro, Kentaro Sato, Naruhiko Nomura, Hiroshi Suganuma, Kenji Takada, Naoki Nii, Takanobu Fujimura, Teruaki Inoue y Shinobu Satonaka. Investigation and Research Into CAE Technique for Spot Weld Rupture (Part 1)~Effect of Tensile Speed on Fracture Strength of Various Joints. Warrendale, PA: SAE International, mayo de 2005. http://dx.doi.org/10.4271/2005-08-0235.
Texto completo