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Showing 1 to 20 of 248 for “"Finite Element Method (FEM)"”.
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Embrittlement and Flow Localization of Reactor Structural Materials
Notch effects have been analyzed utilizing finite element method (FEM) and EBSD misorientation map for unirradiated and irradiated 316L stainless steel. The major issue of interest is the possibility that low ductility, often found following irradiation exposure, will translate into low notch …
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Uma estratégia de refinamento auto-adaptativo versão h do método dos elementos finitos aplicada a problemas bi-dimensionais regidos pela equação de campo
… refinement procedure (h-version) for the Finite Element Method (FEM) solution of two dimensional potential problems is studied. The mesh refinement strategy and the a-posteriori error analysis are also discussed. The Galerkin formulation for FEM is utilized and the resulting system of …
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The design of high power ultrasonic transducers
… and applied are the equivalent circuit method and Finite Element Method (FEM). These methods are used in conjunction with each other to design three different transducers, which are then built and tested at low and high powers.
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Análise de aberturas subterrâneas circulares pelo método dos elementos finitos
… numerical analyses are carried out by means of Finite Element Method (FEM) the quadratic isoparametric element being used. Linear and bi-linear elastic behaviours are assumed. Soils heterogeneity and sequential excavation are taken into account. The shield construction method for tunneling in …
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Development of a numerical tool for the optimisation of vascular prosthesis towards physiological compliance
… was to develop a numerical tool, using the Finite Element Method (FEM) to aid in the development and optimization of such a metallic support structure. This tool was used to simulate the behaviour of different designs under the simulated in vivo conditions. The numerical results of the …
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A nonlocal dense granular flow model implemented in the material point method
… flow is implemented in the material point method (MPM), an extension of the finite element method (FEM) for solid mechanics. The nonlocal model used has shown great predictive capability for dense flows when implemented in the finite element framework, but limitations of FEM prevent …
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Sensitivity Enhanced Model Reduction
In this study, we numerically explore methods of coupling sensitivity analysis to the reduced model in order to increase the accuracy of a proper orthogonal decomposition (POD) basis across a wider range of parameters. Various techniques based on polynomial interpolation and basis alteration are …
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Hybridization of the finite element method and the shooting-and-bouncing ray method for scattering and radiation from large and complex targets
… and radiation problems. In this thesis, a hybrid method combining the finite-element method (FEM) and the shooting-and-bouncing-ray (SBR) method is introduced for scattering and radiation problems from large and complex targets with small cavities or microstrip patch antennas. By combining the two …
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Modeling phonon-polariton generation and control in ferroelectric crystals
In this thesis, we present simulations, using Finite Element Method (FEM), of phonon-polariton generation and coherent control in ferroelectric crystals LiNbO₃ and LiTaO₃ through nonlinear electro-optic interactions with ultrashort laser pulses. This direct space-time monitoring platform is used to …
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Rotordynamic Analysis of Theoretical Models and Experimental Systems
… comparison the experimental</p> <p>systems. Finite Element Method (FEM) is used to construct models using Timoshenko</p> <p>beam elements with viscous and hysteretic internal damping. Eigenvalues</p> <p>and eigenvectors of state space equations are used to perform stability analysis, …
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Adaptive Finite Element Methods for Rigid Particulate Flow Problems
… laws of motion). In this work, numerical methods for some prototypical situations are developed, analyzed and validated; all of them are based on the finite element method (FEM). In this context, special emphasis is given to local grid adaptation. The goal is to obtain a high accuracy and, …
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An operator-customized wavelet-finite element approach for the adaptive solution of second-order partial differential equations on unstructured meshes
The Finite Element Method (FEM) is a widely popular method for the numerical solution of Partial Differential Equations (PDE), on multi-dimensional unstructured meshes. Lagrangian finite elements, which preserve C⁰ continuity with interpolating piecewise-polynomial shape functions, are a common …
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Estudo e construção de um motor de indução de rotor externo de pequeno porte utilizado como motor-mancal
… Simulation studies were performed by using the Finite Element Method (FEM), effectively showing that it is possible to control the radial position to keep the rotor spinning. A first prototype was successfully built and tested for a power of 100 W showing good potential for applications in this …
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Analysis and development of a monolithic computational approach for fluid–structure interaction by means of the finite element method
… in the reference configuration by means of the finite element method (FEM). The solution method is validated using numerically computed reference data for a benchmark problem. A novel FEM is introduced for the monolithic computation of FSI allowing a straightforward coupling to further field …
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Downhole Weight on Bit Prediction with Analytical Model and Finite Element Method
… and compared: an analytical model and a finite element method (FEM). In conclusion the analytical model computes faster, but FEM is more accurate. Simulations are performed to verify and compare both methods, where friction factors and WOB are calculated for a horizontal well in Western …
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An Innovative Coupling Scheme of FEM And BEM Solvers
… (MSIC) has been developed for coupling Boundary Element Method (BEM) and Finite Element Method (FEM) solutions in the direct time domain for linear elasticity and wave propagation problems. The MSIC allows for independent selection of time step in each of the solvers and has been shown to be …
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STUDY OF THE LOADING OF PILES USING A SEMI-ANALYTICAL METHOD AND THE DIGITAL IMAGE CORRELATION TECHNIQUE
… are obtained using the eigenvalue/eigenvector method, and another that determines the displacement within the soil domain, which are obtained numerically using the finite difference method. The piles can have any cross-sectional shape, and the soil profiles can comprise as many layers as …
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Trace finite element method for material surface flows
… dissertation studies a geometrically unfitted finite element method (FEM), known as trace FEM, for the numerical solution of the Navier-Stokes problem posed on a closed smooth material surface. The key result proved is an inf-sup stability of the discrete formulation based on standard …
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Formulações semi-empíricas para o colapso hidrostático bi-simétrico de dutos flexíveis
… by a tridimensional solid model based on the Finite Element Method (FEM) demands a big computational effort due, to among others reasons, the complexity of it cross section. In this work it is developed an alternative approach based on rectangular cross sections with equivalent mechanical …
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