Search results for " Finite element method"

showing 10 items of 58 documents

Symmetric boundary element method versus finite element method

2002

The paper examines the effectiveness of the symmetric boundary element formulation when the continuum body is subdivided into large elements called macro-elements. The approach proposed combines a strong reduction of variables with an elastic solution close to the real response. Indeed, if the displacement method is used, this approach permits one to determine for every macro-element a relationship connecting the weighted traction vector defined on the sides of the interface boundary with the node displacement vector of the same boundary and with the external action vector. Such a strategy is very similar to that followed through the finite element method, but with the advantages of having …

Mechanical EngineeringMathematical analysisComputational MechanicsGeneral Physics and AstronomyGeometryMixed finite element methodSingular boundary methodBoundary knot methodFinite element methodComputer Science ApplicationsBoundary elementMechanics of MaterialsAnalytic element methodSymmetric boundary element methodMethod of fundamental solutionsSubstructuringSettore ICAR/08 - Scienza Delle CostruzioniBoundary element methodMathematicsExtended finite element method
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A four-node MITC finite element for magneto-electro-elastic multilayered plates

2013

An isoparametric four-node finite element for multilayered magneto-electro-elastic plates analysis is presented. It is based on an equivalent single-layer model, which assumes the first order shear deformation theory and quasi-static behavior for the electric and magnetic fields. First, the electro-magnetic state of the plate is determined in terms of the mechanical primary variables, namely the generalized displacements, by solving the strong form of the magneto-electric governing equations coupled with the electro-magnetic interface continuity conditions and the external boundary conditions. In turn, this result is used into the layers constitutive law to infer the equivalent single-layer…

Mechanical equilibriumConstitutive equationGeometrylaw.inventionlawmedicineConstitutive relationshipFirst-order shear deformation theoryGeneral Materials ScienceBoundary value problemSettore ING-IND/04 - Costruzioni E Strutture AerospazialiElectric and magnetic fieldCivil and Structural EngineeringMathematicsExtended finite element methodMulti-layered plates Interface stateExternal boundary conditionMagneto-electro-elastic plateMechanical EngineeringMitc finite elementMathematical analysisStiffnessMixed finite element methodFinite element methodComputer Science ApplicationsVibrationStresses Finite element methodModeling and SimulationMagneto-electro-elasticmedicine.symptomComputers & Structures
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A finite element formulation for large deflection of multilayered magneto-electro-elastic plates

2014

An original finite element formulation for the analysis of large deflections in magneto-electro-elastic multilayered plates is presented. The formulation is based on an equivalent single-layer model in which first order shear deformation theory with von Karman strains and quasi-static behavior for the electric and magnetic fields are assumed. To obtain the plate model, the electro-magnetic state is firstly determined and condensed to the mechanical primary variables, namely the generalized displacements. In turn, this result is used to obtain laminate effective stiffness coefficients that allow to express the plate mechanical stress resultants in terms of the generalized displacements and a…

Mechanical equilibriumMaterials sciencebusiness.industryFinite element limit analysisMathematical analysisStructural engineeringMixed finite element methodMagneto-electro-elastic structureFinite element methodMagnetic fieldlaw.inventionlawCeramics and CompositesMITC finite elementsBoundary value problemSettore ING-IND/04 - Costruzioni E Strutture AerospazialibusinessMultilayered plateMagnetoCivil and Structural EngineeringExtended finite element methodComposite Structures
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Analisi numerico-sperimentale sull’influenza dell’attrito nella delaminazione in Modo II

2011

Modo II test di fatica Finite Element Method (FEM) elementi coesivi materiali compositi.
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finite element methods

2017

Two robot patch recovery methods with built-in field equations and boundary conditions superconvergence similarities in standard and mixed finite element methods on the FEM for the Navier-Stokes equations in the domains with corner singularities projections in finite element analysis and application element analysis method and superconvergence quadratic interpolation polynomials in vertices of strongly regular triangulations explicit error bounds for a nonconforming finite element method analysis of the average efficiency of an error estimator on the mesh for difference schemes of higher accuracy for the heat-conduction equation shape design sensitivity formulae approximated by means of a r…

Nonlinear systemMathematical analysisExtrapolationBoundary value problemMixed finite element methodSuperconvergenceGalerkin methodComputer Science::Numerical AnalysisFinite element methodMathematics::Numerical AnalysisMathematicsExtended finite element method
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MAST-2D diffusive model for flood prediction on domains with triangular Delaunay unstructured meshes

2011

Abstract A new methodology for the solution of the 2D diffusive shallow water equations over Delaunay unstructured triangular meshes is presented. Before developing the new algorithm, the following question is addressed: it is worth developing and using a simplified shallow water model, when well established algorithms for the solution of the complete one do exist? The governing Partial Differential Equations are discretized using a procedure similar to the linear conforming Finite Element Galerkin scheme, with a different flux formulation and a special flux treatment that requires Delaunay triangulation but entire solution monotonicity. A simple mesh adjustment is suggested, that attains t…

Nonlinear systemMathematical optimizationDiscretizationDelaunay triangulationCourant–Friedrichs–Lewy conditionshallow waters numerical methods finite element method diffusive model unstructured meshes Delaunay triangulations Voronoi cells unsteady flow backwater effect analytical solutionLinear systemApplied mathematicsGalerkin methodShallow water equationsFinite element methodWater Science and TechnologyMathematics
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On the numerical solution of axisymmetric domain optimization problems by dual finite element method

1994

Shape optimization of an axisymmetric three-dimensional domain with an elliptic boundary value state problem is solved. Since the cost functional is given in terms of the cogradient of the solution, a dual finite element method based on the minimum of complementary energy principle is used. © 1994 John Wiley & Sons, Inc.

Numerical AnalysisFinite element limit analysisApplied MathematicsMathematical analysisMixed finite element methodBoundary knot methodFinite element methodComputational MathematicsMethod of fundamental solutionsShape optimizationAnalysisMathematicsExtended finite element methodFree energy principleNumerical Methods for Partial Differential Equations
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Guaranteed lower bounds for cost functionals of time-periodic parabolic optimization problems

2019

In this paper, a new technique is shown for deriving computable, guaranteed lower bounds of functional type (minorants) for two different cost functionals subject to a parabolic time-periodic boundary value problem. Together with previous results on upper bounds (majorants) for one of the cost functionals, both minorants and majorants lead to two-sided estimates of functional type for the optimal control problem. Both upper and lower bounds are derived for the second new cost functional subject to the same parabolic PDE-constraints, but where the target is a desired gradient. The time-periodic optimal control problems are discretized by the multiharmonic finite element method leading to lar…

Optimization problemtime-periodic conditionmultiharmonic finite element methodDiscretizationtwo-sided boundsSystems and Control (eess.SY)010103 numerical & computational mathematicsSystem of linear equationsElectrical Engineering and Systems Science - Systems and Control01 natural sciencesUpper and lower boundsSaddle pointFOS: MathematicsFOS: Electrical engineering electronic engineering information engineeringApplied mathematicsMathematics - Numerical AnalysisBoundary value problem0101 mathematicsMathematics - Optimization and ControlMathematicsosittaisdifferentiaaliyhtälöt35Kxx 65M60 65M70 65M15 65K10parabolic optimal control problemsNumerical Analysis (math.NA)matemaattinen optimointiOptimal controlFinite element method010101 applied mathematicsComputational MathematicsComputational Theory and MathematicsOptimization and Control (math.OC)Modeling and Simulationa posteriori error analysisnumeerinen analyysiguaranteed lower boundsComputers & Mathematics with Applications
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The Global-Local Approach for Damage Detection in Composite Structures and Rails

2021

Structural components with waveguide geometry can be probed using guided elastic waves. Analytical solutions are prohibitive in complex geometries, especially in presence of structural discontinuities or defects. The Global-Local (GL) approach provides the solution by splitting the waveguide in “local” and “global” regions. The “local” region contains the part of the structure responsible for the complex scattering of an incident wave. What happens in this region cannot be reproduced analytically. The “global” region is regular and sufficiently far from the scatterer, in order to exploit known analytical wave propagation solutions. The proposed GL approach discretizes the local region by re…

PhysicsAircrafts Composite structures Damage detection Global-Local approach Guided waves Rails Scattering Semi-analytical finite element methodGuided waves scattering Global-Local approach damage detection semi-analytical finite element method composite structures aircrafts railsScatteringWave propagationMathematical analysisWaveguide (acoustics)KinematicsClassification of discontinuitiesSettore ICAR/08 - Scienza Delle CostruzioniFinite element methodEnergy (signal processing)Spectral line
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The finite element method for fractional non-local thermal energy transfer in non-homogeneous rigid conductors

2015

Abstract In a non-local fractional-order model of thermal energy transport recently introduced by the authors, it is assumed that local and non-local contributions coexist at a given observation scale: while the first is described by the classical Fourier transport law, the second involves couples of adjacent and non-adjacent elementary volumes, and is taken as proportional to the product of the masses of the interacting volumes and their relative temperature, through a material-dependent, distance-decaying power-law function. As a result, a fractional-order heat conduction equation is derived. This paper presents a pertinent finite element method for the solution of the proposed fractional…

PhysicsFinite element methodNumerical Analysisbusiness.industryApplied MathematicsMathematical analysisFinite differenceFinite element method; Fractional calculus; Long-range heat transport; Non-homogeneous conductors; Modeling and Simulation; Numerical Analysis; Applied MathematicsMixed finite element methodFractional calculuFinite element methodFractional calculussymbols.namesakeLong-range heat transportFourier transformModeling and SimulationsymbolsHeat equationNon-homogeneous conductorbusinessSettore ICAR/08 - Scienza Delle CostruzioniNumerical AnalysiThermal energyExtended finite element method
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