Academic literature on the topic 'Fibre level simulation'
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Journal articles on the topic "Fibre level simulation"
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Huang, Jin, Bo Xu, and Kun Qiu. "Modeling and Simulation of FC-AE-ASM Network." Advanced Materials Research 748 (August 2013): 941–45. http://dx.doi.org/10.4028/www.scientific.net/amr.748.941.
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Fibre Channel (FC) as a Universal Avionics Network (UAN) candidate solution for the advanced integrated avionics systems can enable high-bandwidth, low-latency, high-reliability and hard real-time communication on aircraft platforms spanning military and commercial applications. Fibre Channel Avionics Environment-Anonymous Subscriber Messaging protocol (FC-AE-ASM) is one of the five high level protocols in fiber channel avionic environment which is used to transport command, control, signal processing and sensor / video data of the aircraft[1,2].The objective of this paper is to conduct a modeling and simulation on the performance of the FC–AE-ASM network. Through modeling the message transmission of the FC-AE-ASM with accompanying Eclipse, some network performance parameters such as bandwidth, throughput and end-to-end message delay can be gained and analyzed.
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Monzón, Mario, Rubén Paz, Martí Verdaguer, Luis Suárez, Pere Badalló, Zaida Ortega, and Noelia Diaz. "Experimental Analysis and Simulation of Novel Technical Textile Reinforced Composite of Banana Fibre." Materials 12, no. 7 (April 7, 2019): 1134. http://dx.doi.org/10.3390/ma12071134.
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The use of natural fibres allows reducing environmental impact, due to their natural renewable origin and the lower energy needed for their production and processing. This work presents the mechanical characterization of a newly developed technical textile, with banana fibre treated by enzymes, comparing experimental results with numerical simulation based on the definition of the unit cell at micromechanical level. The experimental test shows that the composite with the fabric of banana fibre presents worse mechanical behaviour than the one with commercial flax fibre. The presence of wool, necessary for producing the yarn, reduces the mechanical properties of the banana textile. The numerical simulation had an acceptable error compared with the experimental results, with a global average error of 9%, showing that the predictive modelling based on the multiscale method is suitable for the design process of this kind of composite.
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Vigliotti, A., R. M. McMeeking, and V. S. Deshpande. "Simulation of the cytoskeletal response of cells on grooved or patterned substrates." Journal of The Royal Society Interface 12, no. 105 (April 2015): 20141320. http://dx.doi.org/10.1098/rsif.2014.1320.
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We analyse the response of osteoblasts on grooved substrates via a model that accounts for the cooperative feedback between intracellular signalling, focal adhesion development and stress fibre contractility. The grooved substrate is modelled as a pattern of alternating strips on which the cell can adhere and strips on which adhesion is inhibited. The coupled modelling scheme is shown to capture some key experimental observations including (i) the observation that osteoblasts orient themselves randomly on substrates with groove pitches less than about 150 nm but they align themselves with the direction of the grooves on substrates with larger pitches and (ii) actin fibres bridge over the grooves on substrates with groove pitches less than about 150 nm but form a network of fibres aligned with the ridges, with nearly no fibres across the grooves, for substrates with groove pitches greater than about 300 nm. Using the model, we demonstrate that the degree of bridging of the stress fibres across the grooves, and consequently the cell orientation, is governed by the diffusion of signalling proteins activated at the focal adhesion sites on the ridges. For large groove pitches, the signalling proteins are dephosphorylated before they can reach the regions of the cell above the grooves and hence stress fibres cannot form in those parts of the cell. On the other hand, the stress fibre activation signal diffuses to a reasonably spatially homogeneous level on substrates with small groove pitches and hence stable stress fibres develop across the grooves in these cases. The model thus rationalizes the responsiveness of osteoblasts to the topography of substrates based on the complex feedback involving focal adhesion formation on the ridges, the triggering of signalling pathways by these adhesions and the activation of stress fibre networks by these signals.
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Arnold, Edith M., and Scott L. Delp. "Fibre operating lengths of human lower limb muscles during walking." Philosophical Transactions of the Royal Society B: Biological Sciences 366, no. 1570 (May 27, 2011): 1530–39. http://dx.doi.org/10.1098/rstb.2010.0345.
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Muscles actuate movement by generating forces. The forces generated by muscles are highly dependent on their fibre lengths, yet it is difficult to measure the lengths over which muscle fibres operate during movement. We combined experimental measurements of joint angles and muscle activation patterns during walking with a musculoskeletal model that captures the relationships between muscle fibre lengths, joint angles and muscle activations for muscles of the lower limb. We used this musculoskeletal model to produce a simulation of muscle–tendon dynamics during walking and calculated fibre operating lengths (i.e. the length of muscle fibres relative to their optimal fibre length) for 17 lower limb muscles. Our results indicate that when musculotendon compliance is low, the muscle fibre operating length is determined predominantly by the joint angles and muscle moment arms. If musculotendon compliance is high, muscle fibre operating length is more dependent on activation level and force–length–velocity effects. We found that muscles operate on multiple limbs of the force–length curve (i.e. ascending, plateau and descending limbs) during the gait cycle, but are active within a smaller portion of their total operating range.
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Kondora, Grzegorz, and Dariusz Asendrych. "Modelling the Dynamics of Flexible and Rigid Fibres." Chemical and Process Engineering 34, no. 1 (March 1, 2013): 87–100. http://dx.doi.org/10.2478/cpe-2013-0008.
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Abstract A particle-level simulation technique has been developed for modelling fibre suspension flow in a converging channel of a papermachine headbox. The fibre model is represented by a chain of elements connected together. The model was verified by the simulation of rigid fibre dynamics in a simple shear flow. The period of rotation was found to be in a very good agreement with theory and reference data. The model was then employed to simulate fibre motion in a converging channel of a papermachine headbox. Fibre suspension motion was resolved using two-step procedure. Velocity field was calculated by means of a commercial CFD code ANSYS Fluent with RSM turbulence model applied and used as an input to the in-house code allowing to simulate fibre dynamics. Results of the calculations were used to construct the fibre orientation probability distribution (FOPD) which was found to be consistent with available experimental data.
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Sanusi, H., M. S. Hussin, A. R. Yuzairi, L. H. Peng, and M. F. A. Ahmad. "Finite element analysis of drilling unidirectional CFRP in different ply orientation." Journal of Mechanical Engineering and Sciences 14, no. 3 (September 30, 2020): 7258–68. http://dx.doi.org/10.15282/jmes.14.3.2020.25.0570.
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In the new era of Industrial Revolution 4.0 (IR 4.0), the manufacturing processes are facing a new level of flexible mass production technologies. Hence, the high demands for simulations data of manufacturing production and operation are required for developing a Cyber-Physical Systems of smart machines. Some composite machining processes could be very expansive. Simulation is needed to reduce the manufacturing time and cost. Without considering the suitable parameter of drilling, damage occurs at the region over the hole’s boundary after the drilling operation is done. Thus, the goal of this research is to investigate the effects of drilling cutting parameter such as thrust force, drilling-induced damage and stress distribution of reinforcing carbon composite polymer (CFRP) laminate by developing a user-defined material model (VUMAT) subroutine in ABAQUS/EXPLICIT (ABAQUS, Dassault Systèmes®) for different fibre ply orientations. The failure mode such as fibre tensile failure, fibre compressive failure, matrix cracking and matrix crushing was modelled and analysed based on Hashin and Puck’s criterion. The stages of drilling operation were observed and described in this paper with the drilling cutting parameter and the damage of composite was finely defined. The results proved that the relationship of thrust force is directly proportional to the feed rate with the difference of computational model are 8 % higher than the experiment. Among the ply orientation sequence applied in the simulation, the result shows that [ / / ] and [ / / ] ply having higher thrust force with 401.84 N.mm and 390.53 N.mm at 500 mm/min feed rate as delamination extent, as the frequency of fiber pulls out at the exit region of the drilled hole increases as compared to the restricted fiber ply orientation 0˚ and 90˚.
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Heimbs, Sebastian, Tim Wagner, Heinz Meister, Clemens Brand, and Mircea Calomfirescu. "Bird strike on aircraft radome: Dynamic characterisation of quartz fibre composite sandwich for accurate, predictive impact simulations." EPJ Web of Conferences 183 (2018): 01007. http://dx.doi.org/10.1051/epjconf/201818301007.
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This study assesses the bird strike resistance of the satellite communication (SatCom) radome of a medium altitude, long endurance (MALE) remotely piloted aircraft system (RPAS), which is designed as a lightweight sandwich structure with thin quartz fibre composite skins and a cellular honeycomb core. In order to perform accurate, predictive numerical bird strike simulations, the building block approach was applied, involving extensive experimental characterisation and model validation of the materials and structures from simple coupon level up to full-scale radome level. Coupon tests of the quartz fibre composite skin material under high-rate dynamic loading revealed significant strain rate effects, which needed to be taken into account in the simulation model in order to predict the structural response under high-velocity bird strike loading. In summary, this work presents a systematic and detailed approach for obtaining validated modelling methods for high-velocity impact analyses, which could be used efficiently for various design and parameter studies during the development of the SatCom radome.
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Muna, Isyna Izzal, and Magdalena Mieloszyk. "Temperature Influence on Additive Manufactured Carbon Fiber Reinforced Polymer Composites." Materials 14, no. 21 (October 26, 2021): 6413. http://dx.doi.org/10.3390/ma14216413.
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The popular applications of Additive Manufactured (AM) polymer materials in engineering, medical, and industrial fields have been widely recognized due to their high-speed production despite their complex design shapes. Fused Deposition Modeling (FDM) is the technique that has become the most renowned AM process due to its simplicity and because it is the cheapest method. The main objective of this research is to perform a numerical simulation of the thermo-mechanical behaviour of AM polymer with continuous carbon fibre reinforcement exposed to elevated temperatures. The influence of global thermal loads on AM material was focused on mechanical property changes at the microscale (level of fiber–matrix interaction). The mechanical response (strain/stress distribution) of the AM material on the temperature loading was modelled using the finite element method (FEM). The coupled thermal-displacement analysis was used during the numerical calculations. The strain in the sample due to its exposition on elevated temperature was measured using fibre Bragg grating (FBG) sensors. The numerical results were compared with the experimental results achieved for the sample exposure to the same thermal conditions showing good agreement. A strong influence of the temperature on the matrix structure and the condition of bondings between fibres and matrix was observed.
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Yi, T. "The Progressive Failure Analysis of Uni-Directional Fibre Reinforced Composite Laminates." Journal of Mechanics 36, no. 2 (February 24, 2020): 159–66. http://dx.doi.org/10.1017/jmech.2019.55.
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ABSTRACTThe three dimensional standard damage model developed by Lavedeze et.al [9, 13] for uni-directional fibre reinforced ply is implemented into the nonlinear solution of NX Nastran within composite solid element to analyze the progressive damage process and ultimate failure of fibre reinforced composite laminates. This ply level meso-damage-constitutive-model takes into account main damage mechanisms including fibre breaking, matrix transverse cracking, and fibre/matrix de-bonding; also considers contributions like plasticity coupling, damage delay effects, and elastic nonlinearity in fibre compression. Dissipated energy and damage status are also introduced to reflect the damage condition on the macrostructural-level. Using the implemented code, simulation is carried out on the uniaxial tension of a [±45]2s laminate with IM6/914 material, wherein the predicted ply shear rupture stress matches the experimental results very well and better than the theoretical predictions in literature. Moreover, a [-45/0/45/90] holed laminate loaded in tension is simulated to show the complex behavior of subcritical damage evolution and failure process in the composite structure. The composite solid element with damage model supported in NX Nastran is shown to be a reliable tool to analyze the progressive failure of uni-directional fibre reinforced composite laminates.
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Fat Cheung, Adrien M., and Klaudio Bari. "Novel Reactive Flex Configuration in Kiwi Wing Foil Surfboard." Journal of Composites Science 6, no. 1 (December 26, 2021): 6. http://dx.doi.org/10.3390/jcs6010006.
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The creation of an ideal surfboard is art. The design and construction depend on the individual surfer’s skill level and type of the required performance. In this research, four fuselage concepts were carefully explored to meet the following unique needs: lightweight, strong, and a fast-manufacturing process. The fuselages were manufactured by compression moulding using skin and core materials. The skin material was selected to be unidirectional (UD) carbon fibre, discontinuous carbon fibre (SMC) and Filava quadriaxial fibre impregnated with epoxy, while the core material was selected to be lightweight PVC foam. To assess the mechanical performance, three-point bending has been performed according to BS-ISO 14125 and validated using Finite Element Analysis (FEA) using Ansys software. As expected, the flexural test revealed that the UD carbon fibre fuselage was the strongest and SMC was the weakest, while large deflection was seen in Filava fibre fuselages before failure, showing great reactive flex that promotes projection during surfing. The experimental results show good agreement with FEA simulation, and the locations of the physical failure in the fuselage matches the location of maximum flexural stress obtained from FEA simulation. Although all fuselages were found to carry a surfer weight of 150 kg, including a factor of safety 3, except the SMC fuselage, due to shrinkage. The Filava fibre fuselages were seen to have a large deflection before failure, showing great flexibility to handle high ocean waves. This promotes the potential use of reactive flex in high performance sports equipment, such as surfing boards. A large shrinkage must be taken under consideration during compression moulding that depends on fibre orientation, resin nature, and part geometry.
Dissertations / Theses on the topic "Fibre level simulation"
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Fan, Xijun. "Numerical study on some rheological problems of fibre suspensions." School of Aerospace, Mechanical & Mechatronic Engineering, 2006. http://hdl.handle.net/2123/1096.
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Doctor of philosophy (Ph D)This thesis deals with numerical investigations on some rheological problems of fibre suspensions: the fibre level simulation of non-dilute fibre suspensions in shear flow; the numerical simulation of complex fibre suspension flows and simulating the particle motion in viscoelastic flows. These are challenging problems in rheology. Two numerical approaches were developed for simulating non-dilute fibre suspensions from the fibre level. The first is based on a model that accounts for full hydrodynamic interactions between fibres, which are approximately calculated as a superposition of the long-range and short-range hydrodynamic interactions. The long-range one is approximated by using slender body theory and includes infinite particle interactions. The short-range one is approximated in terms of the normal lubrication forces between close neighbouring fibres. The second is based on a model that accounts only for short-range interactions, which comprise the lubrication forces and normal contact and friction forces. These two methods were applied to simulate the microstructure evolution and rheological properties of non-dilute fibre suspensions. The Brownian configuration method was combined with the highly stable finite element method to simulate the complex flow of fibre suspensions. The method is stable and robust, and can provide both micro and macro information. It does not require any closure approximations in calculating the fibre stress tensor and is more efficient and variance reduction, compared to CONNFFESSITT, for example. The flow of fibre suspensions past a sphere in a tube and the shear induced fibre migration were successfully simulated using this method The completed double layer boundary element method was extended to viscoelastic flow cases. A point-wise solver was developed to solve the constitutive equation point by point and the fixed least square method was employed to interpolate and differentiate data locally. The method avoids volume meshing and only requires the boundary mesh on particle surfaces and data points in the flow domain. A sphere settling in the Oldroyd-B fluid and a prolate spheroid rotating in shear flow of the Oldroyd-B fluid were simulated. Based on the simulated orbit of a prolate spheroid in shear flow, a constitutive model for the weakly viscoelastic fibre suspensions was proposed and its predictions were compared with some available experimental results. All simulated results are in general agreement with experimental and other numerical results reported in literature. This indicates that these numerical methods are useful tools in rheological research.
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Laurencin, Tanguy. "Étude de la rhéologie des suspensions de fibres non-newtoniennes par imagerie et simulation numérique 3D à l'échelle des fibres." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI013/document.
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Ce travail porte sur la mise en forme des matériaux composites à matrice polymère renforcée par des fibres courtes dont les performances physiques et mécaniques sont directement reliées à la distribution spatiale et à l’orientation des renforts employés. Il se focalise sur l’étude des mécanismes de déformation se produisant au cours de l’écoulement de ces systèmes qui se comportent comme des suspensions de fibres non-newtoniennes. Le problème est abordé par une procédure originale combinant images 3D acquises en temps réel et simulations numériques avancées, réalisées à l’échelle des fibres. Dans le premier cas, des suspensions modèles avec fluide suspensif non-newtonien ont été déformées en compression dans des conditions confinées dans un microtomographe à rayons X synchrotron. Cette technique a permis l’acquisition en temps réel de clichés 3D à forte résolution spatiale de l’écoulement des suspensions. Dans le deuxième cas, un code de calculs éléments finis 3D a été utilisé, celui-ci étant capable de décrire finement des objets immergés dans des fluides non-newtoniens, par des level-sets et des techniques de remaillage anisotrope. La pertinence des simulations numériques dans les régimes de concentration dilués à semi-dilués a été jaugée par une comparaison expériences-simulations avancée.De là, dans le régime de concentration dilué, nous montrons que le confinement de l’écoulement et le comportement rhéofluidifiant du fluide suspensif ont une influence mineure sur la cinématique des fibres, si ces dernières sont suffisamment éloignées des plateaux de compression. Si ce prérequis n’est pas respecté, l’effet du confinement devient important. Des modifications au modèle heuristique d’haltère de la littérature ont été proposées pour corriger la cinématique de fibres. Dans le régime semi-dilué, des déviations de la cinématique de fibres sont également observées au cœur des suspensions. Ces déviations sont principalement liées aux interactions hydrodynamiques entre fibres suffisamment voisines. La cinématique des fibres prédite par le modèle de Jeffery et les approximations de champ affine sont mises en défaut. Dans le régime concentré, si l’évolution de l’orientation globale de la suspension est étonnamment bien décrite par l’équation de Jeffery, de très importantes fluctuations des champs de translation et de rotation des fibres sont observées à l’échelle des fibres. Celles-ci sont induites par les nombreux contacts entre fibres qui peuvent par ailleurs être correctement prédits par le modèle de tubeThis study focuses on the processing of short fibre-reinforced polymer composites. The physical and mechanical properties of these materials are mainly affected by the position and orientation distribution of fibres induced during their forming. Thus, we analysed the flow-induced micro-mechanisms that arose at the fibre scale during the forming stage of these complex systems which behave as non-Newtonian fibre suspensions. For that purpose, an original approach was developed by combining 3D imaging technique and direct numerical simulation, both performed at the fibre scale. Hence, several model fibre suspensions with a non-Newtonian suspending fluid and with a concentration regime that ranged from dilute to concentrated were prepared . They were subjected to confined lubricated compression loadings using a rheometer mounted on a synchrotron X-ray microtomograph. Thanks to very short scanning times, 3D images of the evolving fibrous microstructures at high spatial resolution were recorded in real-time. These experiments were also simulated using a dedicated Finite Element library enabling an accurate description of fibre kinematics in complex suspending fluids thanks to high performance computation, level sets and adaptive anisotropic meshing. The efficiency of the numerical simulation from the dilute to semi-dilute concentration regimes was assessed through experimental and numerical comparisons.Then, we showed that the confinement effect and the non-Newtonian rheology of the suspending fluid had a weak effect on the fibre kinematics, if the fibres were sufficiently far from the compression platens, typically the fibre-platen distance should be larger than twice the fibre diameter. Otherwise, confinement effects occurred. Some extensions of the dumbbell model were proposed to correct the fibre kinematics in this flow conditions. In semi-dilute concentration, deviations of the fibre kinematics compared to the Jeffery’s predictions were also observed and related to hydrodynamic interactions between fibres. In this case, the predictions of Jeffery’s model and the related assumption of affine fibre motions are less relevant. In the concentrated regime, even if the overall orientation of fibre suspension could be astonishingly well described by using the Jeffery’s model, strong fluctuations on each fibre motion and rotation were observed. These deviations were induced by the numerous fibre-fibre contacts, which could be correctly predicted by the tube model
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Lo, Shin-en. "A Fire Simulation Model for Heterogeneous Environments Using the Level Set Method." Scholarship @ Claremont, 2012. http://scholarship.claremont.edu/cgu_etd/72.
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Wildfire hazard and its destructive consequences have become a growing issue around the world especially in the context of global warming. An effective and efficient fire simulation model will make it possible to predict the fire spread and assist firefighters in the process of controlling the damage and containing the fire area. Simulating wildfire spread remains challenging due to the complexity of fire behaviors. The raster-based method and the vector-based method are two major approaches that allow one to perform computerized fire spread simulation. In this thesis, we present a scheme we have developed that utilizes a level set method to build a fire spread simulation model. The scheme applies the strengths and overcomes some of the shortcomings of the two major types of simulation method. We store fire data and local rules at cells. Instead of calculating which are the next ignition points cell by cell, we apply Huygens' principle and elliptical spread assumption to calculate the direction and distance of the expanding fire by the level set method. The advantage to storing data at cells is that it makes our simulation model more suitable for heterogeneous fuel and complex topographic environment. Using a level set method for our simulation model makes it possible to overcome the crossover problem. Another strength of the level set method is its continuous data processing. Applying the level set method in the simulation models, we need fewer vector points than raster cells to produce a more realistic fire shape. We demonstrate this fire simulation model through two implementations using narrow band level set method and fast marching method. The simulated results are compared to the real fire image data generated from Troy and Colina fires. The simulation data are then studied and compared. The ultimate goal is to apply this simulation model to the broader picture to better predict different types of fires such as crown fire, spotting fires, etc.
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Magarabooshanam, Harikrishnan. "Fire performance of complex light gauge steel framed wall systems." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/205877/1/Harikrishnan_Magarabooshanam_Thesis.pdf.
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Pacquaut, Guillaume. "Couplage Stokes/Darcy dans un cadre Level-set en grandes déformations pour la simulation des procédés d'élaboration par infusion de résine." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2010. http://tel.archives-ouvertes.fr/tel-00609670.
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Ce travail de recherche propose un modèle numérique pour simuler les procédés par infusion de résine en utilisant la méthode des éléments finis. Ce modèle permet de représenter l'écoulement d'une résine liquide dans des préformes poreuses subissant de grandes déformations. Dans cette étude, une modélisation macroscopique est utilisée. Au niveau du procédé, une zone de résine liquide est déposée sur les préformes. Ces dernières étant considérées comme un milieu poreux. Les équations de Stokes et de Darcy sont utilisées pour modéliser l'écoulement de la résine respectivement dans le drainant et dans les préformes. L'originalité du modèle réside dans le fait qu'un seul maillage est utilisé pour les deux milieux. La discrétisation est réalisée avec des éléments mixtes : dans Stokes, des éléments P1+/P1 sont utilisés et dans Darcy, des éléments P1/P1 stabilisés avec une formulation multi-échelle sont employés. Des fonctions distances signées sont utilisées pour représenter l'interface entre Stokes-Darcy et pour représenter le front de résine. Concernant la déformation des préformes, une formulation Lagrangienne réactualisée est utilisée. Dans cette formulation Lagrangienne, le comportement des préformes humides est représenté à l'aide du modèle de Terzaghi dans lequel les préformes sèches ont un comportement élastique non-linéaire. La perméabilité est reliée à la porosité via la relation de Carman-Kozeny. Celle-ci est déterminée à partir de l'équation de conservation de la masse. Ce modèle a été implémenté dans ZéBuLoN. Plusieurs simulations numériques d'infusion de résine sont présentées à la fin de ce manuscrit.
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Desfossés, Foucault Alexandre. "Simulation numérique de feux de forêt avec réinitialisation et contournement d’obstacles." Thèse, 2010. http://hdl.handle.net/1866/3797.
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Ce travail présente une technique de simulation de feux de forêt qui utilise la
méthode Level-Set. On utilise une équation aux dérivées partielles pour déformer
une surface sur laquelle est imbriqué notre front de flamme. Les bases mathématiques
de la méthode Level-set sont présentées. On explique ensuite une méthode
de réinitialisation permettant de traiter de manière robuste des données réelles et
de diminuer le temps de calcul. On étudie ensuite l’effet de la présence d’obstacles
dans le domaine de propagation du feu. Finalement, la question de la recherche
du point d’ignition d’un incendie est abordée.This work presents a forest fire simulation model which uses the Level-Set method. We use a partial differential equation to deform a surface on which our flame front is inscribed. The mathematical foundations of the Level-set method are presented. We then explain a reinitialization method that allows us to treat in a robust way real data and to reduce the calculation time. The effect of the presence of barriers in the fire propagation domain is also studied. Finally, we make an attempt to find the ignition point of a forest fire.
Books on the topic "Fibre level simulation"
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Kruk, R. V. Low level flight performance, and air combat maneuvering performance in a simulator with a fiber optic helmet mounted display system. New York: American Institute of Aeronautics and Astronautics, 1989.
Find full textBook chapters on the topic "Fibre level simulation"
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LaCroix, Jacob J., Qinglin Li, Soung-Ryoul Ryu, Daolan Zheng, and Jiquan Chen. "Simulating Fire Spread with Landscape Level Edge Fuel Scenarios." In Remote Sensing and Modeling Applications to Wildland Fires, 267–79. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-32530-4_18.
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Tserpes, Konstantinos, Elli Moutsompegka, Mareike Schlag, Kai Brune, Christian Tornow, Ana Reguero Simón, and Romain Ecault. "Characterization of Pre-bond Contamination and Aging Effects for CFRP Bonded Joints Using Reference Laboratory Methods, Mechanical Tests, and Numerical Simulation." In Adhesive Bonding of Aircraft Composite Structures, 51–117. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-319-92810-4_2.
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AbstractIn this chapter, the pre-bond contamination and ageing effects on carbon fiber reinforced plastic (CFRP) adherends and CFRP bonded joints are characterized by means of reference laboratory non-destructive testing (NDT) methods, mechanical tests, and numerical simulation. Contaminations from two fields of application are considered, namely in aircraft manufacturing (i.e. production) and for in-service bonded repair. The production-related scenarios comprise release agent, moisture, and fingerprint, while the repair-related scenarios comprise fingerprint, thermal degradation, de-icing fluid, and a faulty curing of the adhesive. For each scenario, three different levels of contamination were pre-set and applied, namely low, medium and high level. Furthermore, two types of samples were tested, namely coupons and pilot samples (a stiffened panel and scarf repairs). The CFRP adherends were contaminated prior to bonding and the obtained surfaces were characterized using X-ray photoelectron spectroscopy. After bonding, the joints were tested by ultrasonic testing. To characterize the effects of each contamination on the strength of the bonded joints, mode-I and mode-II fracture toughness tests, and novel centrifuge tests were conducted on the coupons, while tensile tests were performed on the scarfed samples. Additionally, numerical simulation was performed on CFRP stiffened panels under compression using the LS-DYNA finite element (FE) platform.
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Beyki, Shahab Mohammad, Aldina Santiago, Luís Laím, and Helder D. Craveiro. "Wildfire and evacuation simulation: An overview of research, development, and practice." In Advances in Forest Fire Research 2022, 815–21. Imprensa da Universidade de Coimbra, 2022. http://dx.doi.org/10.14195/978-989-26-2298-9_124.
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Wildfires have been growing dramatically over the past decades due to climate changes, global warming, droughts and forest landscape, and vegetation changes. Increasing losses due to wildfires have been a significant concern; therefore, protective measures are being taken to mitigate the risk of health hazards and even deaths. This paper assesses and reviews the approaches to fire spread and propagation simulation to predict the fire spread characteristics. These simulations are essential to determine the evacuation necessity and requirement. The assessment of evacuation triggers is investigated according to the available literature and studies on simulation and computational fluid dynamic (CFD) modeling of wildfire and fire spread are reviewed. In addition, the modeling and simulation of evacuation decisions, residents' evacuation, traffic patterns, and the evacuation trigger models are presented and discussed. All mentioned simulations are modeled on different scales, i. e. microscale, mesoscale and macroscale, based on the desired criteria assessment of each case study. These approaches are distinguished basically by their ability to model an area of certain extent, i. e. scale, and their accuracy in attaining the desired, analysis, data and prediction, i. e. detail level, and selecting one approach over the others is always a trade-off between these two criteria.
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Staudinger, Severin. "Forest Fire Simulation." In Advances in Systems Analysis, Software Engineering, and High Performance Computing, 122–32. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-7156-9.ch009.
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In this chapter a heuristic forest fire model based on cellular automata is presented and realized for efficiency reasons with the DataFlow programming approach. Real-world images taken by satellites are analyzed and used as the basis for simulations. In the presented forest fire model, natural influences like wind strength and direction, burning behavior, as well as different levels of inflammability are considered. The DataFlow implementation on an FPGA-based Maxeler MAX3 Vectis card was compared to a sequential C version executed on an Intel Xeon E5-2650 2.0 GHz CPU. The author obtained speedups of up to 70 for a strong wind situation and 46 for a random wind setting while reducing energy consumption.
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Staudinger, Severin. "Forest Fire Simulation." In Research Anthology on Ecosystem Conservation and Preserving Biodiversity, 564–74. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-6684-5678-1.ch029.
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In this chapter a heuristic forest fire model based on cellular automata is presented and realized for efficiency reasons with the DataFlow programming approach. Real-world images taken by satellites are analyzed and used as the basis for simulations. In the presented forest fire model, natural influences like wind strength and direction, burning behavior, as well as different levels of inflammability are considered. The DataFlow implementation on an FPGA-based Maxeler MAX3 Vectis card was compared to a sequential C version executed on an Intel Xeon E5-2650 2.0 GHz CPU. The author obtained speedups of up to 70 for a strong wind situation and 46 for a random wind setting while reducing energy consumption.
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Paugam, Ronan, William Mell, Jean-Baptiste Filippi, Melanie Rochoux, and Martin Wooster. "High Resolution Fire Behavior Monitoring and Plume Simulation in the context of Experimental Fire." In Advances in Forest Fire Research 2022, 1134–40. Imprensa da Universidade de Coimbra, 2022. http://dx.doi.org/10.14195/978-989-26-2298-9_172.
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Coupled fire-atmosphere systems are currently developed to respond to the need of operational system in air quality and fire attack management. This work participates to this effort by proposing a simulation strategy where the plume is simulated using fire observation. Such approach can provide reference test case for more complex coupled fire-atmosphere simulation. Using the Forefire-MesoNH system, we simulate the plume evolution of a landscape scale burn where the fire is not simulated as a spreading front but rather prescribed from multiple fix burners controlled with observation data. The simulation of the plume formed from a 7-hectare savannah fire conducted in Kruger National Park in 2014 is demonstrated using helicopter-borne observations georeferenced at 1-m resolution and post-processed to extract information of heat fluxes at pixel level.
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Hassan, Ahmad, Gilbert Accary, Duncan Sutherland, Sofiane Meradji, and Khalid Moinuddin. "Physics-based modelling of junction fires: Sensitivity and Validation studies." In Advances in Forest Fire Research 2022, 315–22. Imprensa da Universidade de Coimbra, 2022. http://dx.doi.org/10.14195/978-989-26-2298-9_50.
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The process of modelling and replicating extreme fire behaviour like junction fire is essential for understanding the phenomena associated with extreme fires. Numerical simulations of junction fires, replicating laboratory-scale experiments, with no imposed wind, were performed for a shrub fuel bed with slopes ranging from 0° to 30°. The simulations of junction fires were conducted for two junction angles 30° and 45°. For each scenario, the sensitivity to a range of numerical and physical parameters was investigated. The rate of spread (ROS) is a key parameter for assessing risks from vegetation fires. Experimental spreading junction fires, conducted at laboratory scale at Coimbra University (Portugal), were simulated using FIRESTAR3D - a three-dimensional physics-based fire model. To ensure the robustness of simulations, sensitivity analyses were carried out by varying the grid resolution, domain size, different fuel characteristics, as well as some of the thermo-physical parameters. The corresponding simulations were carried out using a single and two descriptions levels of the shrub: the vegetation was represented using only one cylindrical-shaped solid-fuel type (excelsior fuel using the characteristic parameters for Erica shrub), or two fuel by adding the contribution of twigs of various diameters up to 6 mm while keeping the same packing ratio. Finally, the validation of FIRESTAR3D simulations was achieved through the comparison of predicted and measured ROS values. The experimental trends of the compared quantities were well reproduced by the simulations. Accelerating and decelerating propagation phases were observed in all simulations, with a dependence on the slope angle, while the maximum rate of spread depends critically on the junction angle. As it was the case of other wildfires simulated by FIRESTAR3D, it was found that this fully-physical model is capable of simulating junction fire propagation. There are several processes associated with the development of a junction fire behaviour, in which dramatic changes in fire behaviour can occur with little change in various fuel, weather and topographical parameters. In a subsequent study, we aim to develop an understanding of junction fire behaviour taking into account essential parameters that affect the behaviour, namely: slope, junction angle, and driving wind velocity.
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Wu Gillies, H. "Queensland mine emergency level exercises assisted by fire simulation." In 11th US/North American Mine Ventilation Symposium 2006, 351–58. Taylor & Francis, 2006. http://dx.doi.org/10.1201/9781439833391.ch50.
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Behnam, Behrouz. "Simulating Post-Earthquake Fire Loading in Conventional RC Structures." In Modeling and Simulation Techniques in Structural Engineering, 425–44. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-0588-4.ch015.
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Post-earthquake fire (PEF) is one of the most complicated problems resulting from earthquake, presenting a serious risk to urban buildings. As most standards and codes ignore the possibility of PEF, buildings are too weak under PEF loads. This chapter is to investigate the effects of PEF loads on partially damaged RC buildings located in urban regions. To do that, a methodology named sequential analysis is introduced here via which the structural performance at various performance levels is evaluated under fire and PEF scenarios. Numerically, in order to simulate the earthquake loads, conventional pushover analysis is employed, with an explanation presented in the chapter to introduce the pushover analysis, its advantages and its limitations. To simulate the fire loads, standard fire curve (ISO 834) is used for simplicity.
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Hakes, Raquel S. P., Maria Theodori, Chris Lautenberger, Linda Qian, and Michael J. Gollner. "Community-level risk assessment of structure vulnerability to WUI fire conditions in the 2017 Tubbs Fire." In Advances in Forest Fire Research 2022, 552–57. Imprensa da Universidade de Coimbra, 2022. http://dx.doi.org/10.14195/978-989-26-2298-9_86.
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This study presents a risk analysis for structures in the wildland-urban interface using fragility curves. Reconstruction modelling using the model ELMFIRE is conducted to reproduce exposure conditions for the 2017 Northern California Tubbs Fire as a case study. The reconstruction simulates the distribution of embers, expanding the ability of fire reconstruction to represent conditions during the fire event which are not represented by the flaming fire front. Results from the Tubbs Fire simulation are used to provide exposure conditions to investigate the relationship between exposure conditions, structure and community characteristics, and the damage sustained by a structure in the fire event. A methodology using fragility curves to estimate the probability of destruction, used for risk analysis in other disaster fields, is modified and developed here for application to wildland-urban interface fires. Results of the fragility analysis find that increased ember exposure increases the likelihood of damage or destruction. Relatively low levels of ember exposure still result in relatively high likelihoods of destruction, highlighting the importance of ember spread. Current models cannot simulate structure-to-structure fire spread; additional limitations are highlighted for future work.
Conference papers on the topic "Fibre level simulation"
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Luimula, Mika, Jarmo Majapuro, Fahmi Bellalouna, Anis Jedidi, Brita Somerkoski, and Timo Haavisto. "Hazardous Training Scenarios in Virtual Reality - A Preliminary Study of Training Scenarios for Massive Disasters in Metaverse." In 13th International Conference on Applied Human Factors and Ergonomics (AHFE 2022). AHFE International, 2022. http://dx.doi.org/10.54941/ahfe1002062.
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Simulation training in aviation and maritime is widely used in competence training and assessment. These simulator centres have suffered a lot because of COVID-19 pandemic. Due to the rapid progress in technology development and the pandemic disruptive solutions are intensively searched in vocational and professional training. Flight and maritime simulators are examples of training environments where even hazardous scenarios can be trained in safe conditions. In the previous studies, we have shown that virtual reality offers for other fields tools to create training solutions which can be again hazardous such as our virtual fire safety application used in fire escape. In addition, virtual and augmented reality can be used to create digital learning environments in fire safety prevention training combining physical, psychological, social and pedagogic dimensions. In this paper, we will focus also on virtual fire safety training. Aircraft fires require special treatment in firefighting with regards to the burning materials. This is due to the fact that about half of the aircraft consists of fibre composites, which can release many fine particles that are harmful to the lungs during combustion. However, the training of aircraft firefighting is currently only possible with great effort on a few special training grounds. This training application with multiplayer functionalities was created with Unity game engine. In the design phase, emphasis in the creation of the game was in setting up environment where teamwork and leadership is needed to accomplish the scenario. This approach is quite close to the metaverse concept where social communication is combined with hands on training activities among a large group of participants in an immersive digital training environment. The task of the participants is to first assess the situation, extinguish the fire and prevent the fibres from spreading to the surrounding area. This is done by collecting individual smaller pieces of composite debris or covering larger ones with foam so that they can no longer be carried away with the smoke and wind. Aside from distinguishing the fire at the crash site, the firefighters are also trained to collect debris from the crash site and discard it into the bin. Both tasks are equally as important and require a Standard Operational Procedure guideline in order to realistically implement them in the application. Research was needed to find appropriate solutions for multiplayer functionalities, for fire and smoke behavior, and for extinguishing the fire. Photon Unity Networking framework was used to enable multiplayer functionalities. Fire Propagation plugin in turn enabled to make the fire spread, to configure the appearance of the fire including the size, and the location of flames, the amount and the shape of smoke and sparks based on given requirements. Extinguishing the fire required the use of the water particle system with suitable collision detection. We found multiplayer functionalities to be an important element in virtual training. Scenario was designed so that participants had to communicate well with each other to ensure a fast firefighting. Our application is still in a prototype phase and more efforts will be needed to make the training more realistic. We will in the next phase present the story of the scenario more in details, and increase the stress level of participants by adding more tasks. In addition, our aim is to improve the assessment system analyzing user data, including difficulty levels, high score list, and feedback system. This solution can also be seen as a preliminary study for a massive catastrophe training experiment where tens or hundreds of professionals will be trained in the metaverse environment utilizing in-house metaverse technology.
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Kim, Hyeong-Jin, and David G. Lilley. "Temperature and Smoke Prediction in Structural Fires." In ASME 2001 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/detc2001/cie-21677.
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Abstract Temperature and smoke level predictions in several rooms of a structural fire are possible with a variety of available computer codes. The accuracy and applicability of the results is greatly enhanced though the comparison of the calculations with experimental data. Experimental work assists in understanding fire behavior in structural fires. Temperature measurements at different locations during a house fire provide necessary data for the development of mathematical models, which attempt to simulate the fire on a computer. In this paper, a small 46 square meter single-level house was the subject of a complete experimental burn, with temperature measurements and fire observations during the entire burn. The CFAST computer code (Consolidated Model of Fire Growth and Smoke Transport) can be used to calculate temperatures and smoke levels in the various rooms of the house during the burn. Five fire scenarios are considered in the simulation, with progressively increasing realism regarding the actual fire specification. It is seen that calculations with the most realistic fire simulation (permitting burning in all rooms during the course of the fire) are in very good agreement with the experimental data, with regard to rate of fire spread throughout the structure, and the accuracy of the calculations of flashover, temperatures and smoke levels in each of the rooms.
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Yi, Cong-qin, Yun Luo, and Zheng-ping Zhang. "Simulation of fiber optic liquid level sensor demodulation system." In Third International Conference on Photonics and Image in Agriculture Engineering (PIAGENG 2013), edited by Honghua Tan. SPIE, 2013. http://dx.doi.org/10.1117/12.2019703.
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Kim, Hyeong-Jin, and David G. Lilley. "Accuracy of the Three-Room Simulation of a Ten-Room Large House Fire." In ASME 2002 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/detc2002/cie-34451.
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Calculations (with a 10-room and a simpler 3-room simulation of the large house fire) of temperature and smoke levels in several rooms of a structural fire are possible with the CFAST computer code. The accuracy and applicability of the results is greatly enhanced though the comparison of the calculations with experimental data. Experimental work thereby assists in understanding fire behavior in structural fires. Temperature measurements at different locations during a house fire provide necessary data for the development of mathematical models, which attempt to simulate the fire on a computer. In this paper, a large 170 square meter single-level house was subject to a complete experimental burn, with temperature measurements and fire observations during the entire burn, and subsequent modeling via a detailed 10-room simulation and a simpler 3-room simulation. The CFAST (Consolidated Model of Fire Growth and Smoke Transport) computer code is used to calculate temperatures and smoke levels in the various rooms of the house during the burn (with 10 different rooms). Four fire scenarios are considered in the simulation, with increasing realism regarding the actual fire specification. A simpler calculation (with 3 different rooms) has also done to see if the similar results would be shown with the 10-room simulation. It was found that results for smoke temperature and smoke layer heights were very similar, leading to the conclusion that a 3-room simulation of a 10-room building gives adequate modeling capability of the real structural fire. Computation results give the expected trends (deduced from local point temperature measurements) of initial temperature surge and decay, peak and leveling off temperatures, especially with respect to the northwest bedroom with a closed door. The effect of whether a door of a room would have been open was investigated computationally, with results illustrating far more dangerous smoke temperature and smoke level in the room when its door is open.
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Jafari, Arezou, Krista Henttinen, and Piroz Zamankhan. "Multiscale Modeling of Fluid Turbulence and Flocculation in Industrial Applications." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-79192.
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The present effort is the development of a multiscale modeling, simulation methodology for investigating complex phenomena arising from flowing fiber suspensions. Here, a mathematically rigorous, multiscale modeling methodology is presented capable of coupling behaviors from the Kolmogrov turbulence scale through the full scale system in which a fiber suspension is flowing, (i) a computational simulation framework built around this methodology into which techniques for investigating behaviors at the various scales can be effectively integrated, and (ii) a proof of concept of the developed core technologies using synergetic interactions with experimental studies. Here the key aspect is adaptive hierarchical modeling. Numerical results are presented for which focus is on fiber floc formation and destruction by hydrodynamic forces in turbulent flows. Specific consideration was given to moleculardynamic-type simulations of viscoelastic fibers in which the fluid flow is predicted by a method which is a hybrid between Direct Numerical Simulations (DNS) and Large Eddy Simulation techniques (LES) and fluid fibrous structure interactions (FSI) will be taken into account. The present results may elucidate the physics behind the break up of a fiber floc, opening the possibility for developing a meaningful numerical model of the fiber flow at the continuum level where an Eulerian multi-phase flow model can be developed for industrial use.
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Chow, C. L. "Numerical Simulations on Airflow to the Double-Skin Fac¸ade Cavity by an Adjacent Room Fire." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-37478.
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The architectural feature of double-skin fac¸ades has been proposed in green or sustainable buildings. However, there are potential fire risks and so the design was normally not accepted by the authorities having jurisdictions. The scenario of trapping heat and smoke in the fac¸ade cavity is identified as hazardous and should be better understood. Hot smoke flowing out of openings driven by an adjacent room fire to the double-skin fac¸ade cavity was simulated using computational fluid dynamics (CFD). A five-level building model was taken as an example. A fire occurred in a room at the third level under two different heat release rates of 1 MW and 5 MW, and cavity depths of 0.5 m, 1 m and 2 m were considered. Based on the simulation results, three stages of flame spreading from the room fire to the adjacent fac¸ade cavity were proposed in fire hazard assessment for this architectural feature. Results suggested that wider cavity depths would be more dangerous, having a greater chance to break the adjacent upper interior glass panes. Smoke or even flames can then spread to the upper levels.
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"Atmosphere-fire simulation of effects of low-level jets on pyro-convective plume dynamics." In 20th International Congress on Modelling and Simulation (MODSIM2013). Modelling and Simulation Society of Australia and New Zealand, 2013. http://dx.doi.org/10.36334/modsim.2013.a3.simpson.
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Rahmah, Harisa, Budi Mulyanti, Roer Eka Pawinanto, Arjuni Budi Pantjawati, Lilik Hasanah, and Wawan Purnama. "Simulation of Fiber Optic Chemical Sensor for Monitoring of pH Level." In 2020 3rd International Conference on Information and Communications Technology (ICOIACT). IEEE, 2020. http://dx.doi.org/10.1109/icoiact50329.2020.9332045.
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Steele, Alan L. "New graduate level course in the simulation of optical fiber systems." In Photonics North, edited by John C. Armitage, Roger A. Lessard, and George A. Lampropoulos. SPIE, 2004. http://dx.doi.org/10.1117/12.567254.
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He, Qize, Ofodike A. Ezekoye, Beth Tubbs, and Carl Baldassarra. "CFD Simulation of Smoke Spread Through Elevator Shafts During Fires in High Rise Buildings." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50484.
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Smoke spread through the elevator shafts of high rise buildings has been numerically investigated using the Fire Dynamics Simulator (FDS), which is a computational fluid dynamics (CFD) program suitable for fire induced heat and mass transfer. A model of a high rise building was developed and a fire was set at the first level. The smoke spread process through the elevator shafts was evaluated. The process can be divided into two phases. In the first phase, the smoke gradually fills the shafts, and the gas temperature and pressure in the shafts are transient. After this phase, the smoke fully fills the shafts, the temperature and pressure in the shaft are almost steady, which suggests that the smoke inflow rate equals the outflow rate. Throughout the process, the spatial distributions of temperature and pressure in the elevator shaft under fire situations were reported. The hot fire product gases entering the shaft causes a stack effect, which transports smoke to the upper levels. A method of partially enclosing the elevator lobbies was also investigated by the CFD simulation. The results were compared with the unenclosed situation, and showed that enclosing lobbies not only increases the time needed for the smoke to fully fill the shafts, but also reduces the temperature and pressure differences in the shafts.
Reports on the topic "Fibre level simulation"
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Pullammanappallil, Pratap, Haim Kalman, and Jennifer Curtis. Investigation of particulate flow behavior in a continuous, high solids, leach-bed biogasification system. United States Department of Agriculture, January 2015. http://dx.doi.org/10.32747/2015.7600038.bard.
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Recent concerns regarding global warming and energy security have accelerated research and developmental efforts to produce biofuels from agricultural and forestry residues, and energy crops. Anaerobic digestion is a promising process for producing biogas-biofuel from biomass feedstocks. However, there is a need for new reactor designs and operating considerations to process fibrous biomass feedstocks. In this research project, the multiphase flow behavior of biomass particles was investigated. The objective was accomplished through both simulation and experimentation. The simulations included both particle-level and bulk flow simulations. Successful computational fluid dynamics (CFD) simulation of multiphase flow in the digester is dependent on the accuracy of constitutive models which describe (1) the particle phase stress due to particle interactions, (2) the particle phase dissipation due to inelastic interactions between particles and (3) the drag force between the fibres and the digester fluid. Discrete Element Method (DEM) simulations of Homogeneous Cooling Systems (HCS) were used to develop a particle phase dissipation rate model for non-spherical particle systems that was incorporated in a two-fluid CFDmultiphase flow model framework. Two types of frictionless, elongated particle models were compared in the HCS simulations: glued-sphere and true cylinder. A new model for drag for elongated fibres was developed which depends on Reynolds number, solids fraction, and fibre aspect ratio. Schulze shear test results could be used to calibrate particle-particle friction for DEM simulations. Several experimental measurements were taken for biomass particles like olive pulp, orange peels, wheat straw, semolina, and wheat grains. Using a compression tester, the breakage force, breakage energy, yield force, elastic stiffness and Young’s modulus were measured. Measurements were made in a shear tester to determine unconfined yield stress, major principal stress, effective angle of internal friction and internal friction angle. A liquid fludized bed system was used to determine critical velocity of fluidization for these materials. Transport measurements for pneumatic conveying were also assessed. Anaerobic digestion experiments were conducted using orange peel waste, olive pulp and wheat straw. Orange peel waste and olive pulp could be anaerobically digested to produce high methane yields. Wheat straw was not digestible. In a packed bed reactor, anaerobic digestion was not initiated above bulk densities of 100 kg/m³ for peel waste and 75 kg/m³ for olive pulp. Interestingly, after the digestion has been initiated and balanced methanogenesis established, the decomposing biomass could be packed to higher densities and successfully digested. These observations provided useful insights for high throughput reactor designs. Another outcome from this project was the development of low cost devices to measure methane content of biogas for off-line (US$37), field (US$50), and online (US$107) applications.
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Zywicz, E. A Tow-Level Progressive Damage for Simulating Carbon-Fiber Textile Composites: Interim Report. Office of Scientific and Technical Information (OSTI), July 2000. http://dx.doi.org/10.2172/793579.
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Aalto, Juha, and Ari Venäläinen, eds. Climate change and forest management affect forest fire risk in Fennoscandia. Finnish Meteorological Institute, June 2021. http://dx.doi.org/10.35614/isbn.9789523361355.
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Forest and wildland fires are a natural part of ecosystems worldwide, but large fires in particular can cause societal, economic and ecological disruption. Fires are an important source of greenhouse gases and black carbon that can further amplify and accelerate climate change. In recent years, large forest fires in Sweden demonstrate that the issue should also be considered in other parts of Fennoscandia. This final report of the project “Forest fires in Fennoscandia under changing climate and forest cover (IBA ForestFires)” funded by the Ministry for Foreign Affairs of Finland, synthesises current knowledge of the occurrence, monitoring, modelling and suppression of forest fires in Fennoscandia. The report also focuses on elaborating the role of forest fires as a source of black carbon (BC) emissions over the Arctic and discussing the importance of international collaboration in tackling forest fires. The report explains the factors regulating fire ignition, spread and intensity in Fennoscandian conditions. It highlights that the climate in Fennoscandia is characterised by large inter-annual variability, which is reflected in forest fire risk. Here, the majority of forest fires are caused by human activities such as careless handling of fire and ignitions related to forest harvesting. In addition to weather and climate, fuel characteristics in forests influence fire ignition, intensity and spread. In the report, long-term fire statistics are presented for Finland, Sweden and the Republic of Karelia. The statistics indicate that the amount of annually burnt forest has decreased in Fennoscandia. However, with the exception of recent large fires in Sweden, during the past 25 years the annually burnt area and number of fires have been fairly stable, which is mainly due to effective fire mitigation. Land surface models were used to investigate how climate change and forest management can influence forest fires in the future. The simulations were conducted using different regional climate models and greenhouse gas emission scenarios. Simulations, extending to 2100, indicate that forest fire risk is likely to increase over the coming decades. The report also highlights that globally, forest fires are a significant source of BC in the Arctic, having adverse health effects and further amplifying climate warming. However, simulations made using an atmospheric dispersion model indicate that the impact of forest fires in Fennoscandia on the environment and air quality is relatively minor and highly seasonal. Efficient forest fire mitigation requires the development of forest fire detection tools including satellites and drones, high spatial resolution modelling of fire risk and fire spreading that account for detailed terrain and weather information. Moreover, increasing the general preparedness and operational efficiency of firefighting is highly important. Forest fires are a large challenge requiring multidisciplinary research and close cooperation between the various administrative operators, e.g. rescue services, weather services, forest organisations and forest owners is required at both the national and international level.
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Wang, Chih-Hao, and Na Chen. Investigating the Resilience of Accessibility to Emergency and Lifesaving Facilities under Natural Hazards. Mineta Transportation Institute, May 2022. http://dx.doi.org/10.31979/mti.2022.2126.
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Studying accessibility, including the resilience of city transportation networks, is critical to understand how these networks influence individuals’ mobility and lives. This study developed an analytical research framework to examine the resilience of accessibility to emergency and lifesaving facilities under the threats of natural hazards such as earthquakes and wildfires. With a cumulative-opportunity approach, the authors measured accessibility by counting emergency and lifesaving facilities (including parks, schools, hospitals, roads, and fire stations) that can be reached by driving at the census tract level in San Fernando Valley, CA. With the calculated accessibility, the authors run simulations to collect data showing what would happen if an area were affected by a selected disaster. They then used statistical analysis to identify those areas where accessibility is significantly reduced compared to the original status. A normalized difference accessibility index (NDAI) was further created to suggest plans and strategies to help those vulnerable areas through adding facilities/services or improving transportation infrastructure.