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Showing 1 to 20 of 65 for “"finite element mesh"”.
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Synthesis of a near-optimum finite element mesh
A finite element program post-processor is developed to help synthesize a near-optimum mesh. This post-processor displays, interactively, six different energy functions, along with the usual stress functions. The six energy functions are functions of the energy within each element of the mesh. …
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Selective refinement of a finite element mesh for improved accuracy
The feasibility of refining a finite element by dividing only selected elements is examined. A method is developed which selects these elements so as to maximize the strain energy of the refined mesh. Repeated application of the method results in the generation of a series of refined meshes. The …
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A two-dimensional finite element mesh generator with automatic transitioning capability
A simple, user friendly, mesh generator designed as a preprocessor for two-dimensional finite element codes is presented. The program generates both triangular and quadrilateral two-dimensional elements and has automatic transitioning capability. The required input is the definition of the boundary …
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A finite element mesh optimization procedure using a thermal expansion analogy
Finite element optimum meshes are synthesized by the use of thermal expansion principles in conjunction with an analogous temperature field computed from the element strain energy contents. Elements having high strain energy contents are shrunk and those with low strain energy contents are expanded …
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Optimization Of An Unstructured Finite Element Mesh For Tide And Storm Surge Modeling Applications In The Western North Atlantic Ocean
Recently, a highly resolved, finite element mesh was developed for the purpose of performing hydrodynamic calculations in the Western North Atlantic Tidal (WNAT) model domain. The WNAT model domain consists of the Gulf of Mexico, the Caribbean Sea, and the entire portion of the North Atlantic Ocean …
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Modeling karst aquifer response to rainfall
A finite-element model (HYDMATCH) uses spring hydrograph discharge data to generate a linear regression relation between fracture conductivity and potential gradient in a karst aquifer system. Rainfall excess in the form of potential energy from sinkhole sub-basins is input to element nodes and …
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Size Function Based Mesh Relaxation
… thesis addresses the problem of relaxing a finite element mesh to more closely match a size function. The main contributions include new methods for performing size function based mesh relaxation, as well as an algorithm for measuring the performance of size function based mesh relaxation …
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Elastoplastic nonlinear analysis of nozzle-cylinder intersections subjected to internal and external loads
A three-dimensional finite element analysis utilizing quadratic isoparametric elements is applied to the cylindrical connection. The finite element mesh is highly refined in the three principal directions in the critical regions of sharp discontinuity of geometry and material. Convergence of the …
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Progressive failure analysis of laminated composite structures
… An isoparametric, displacement-based finite element formulation is used to discretize the nonlinear shell equations and an iterative solution is obtained via the Newton-Raphson method. Phenomenological failure criteria are used to predict the onset of damage in the material. Damage is …
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Numerical Analysis of Stable Crack Growth in Elastic-Plastic Materials in Small Scale and General Yielding
… materials are investigated with the aid of the finite element method. The formulation used for steady state crack growth under small scale yielding conditions has the feature that the finite element mesh convects along with the moving crack tip. Various models for plastic flow were used. In Mode …
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A subsurface water quality evaluation system for assessing NPS pollution potential by pesticides
… other two models with SUTRA. An irregular shape finite element mesh generator was developed for fitting the irregular shape watershed boundary and reducing the number of nodes of the finite element mesh. Either transient or steady state flow and transport simulation could be performed with the …
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Predicting Stress Development in Gray Iron Foundry Castings
… gray iron foundry castings. Using a commercial finite element package with a user written element formulation, stresses resulting from thermal displacements in the cooling casting are computed while accounting for cast iron's radically different behavior in tension and compression with a new …
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Three-dimensional finite element modeling of steady state seepage using the computer program 'SEEPS3D'
A three-dimensional finite element model for the analysis of steady state seepage has been presented in this study. The theory of unsaturated flow has been used in the analysis of steady state seepage. The model applies the invariant mesh procedure in the finite element analysis. Galerkin's method …
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Η ΕΦΑΡΜΟΓΗ ΤΗΣ ΣΥΜΜΟΡΦΟΥ ΑΠΕΙΚΟΝΙΣΕΩΣ ΣΤΑ ΠΕΠΕΡΑΣΜΕΝΑ ΣΤΟΙΧΕΙΑ ΓΙΑ ΤΗΝ ΕΠΙΛΥΣΗ ΠΡΟΒΛΗΜΑΤΩΝ ΡΩΓΜΩΝ
… HAS THE APPROPRIATE SQUARE ROOT SINGULARITY. THE ELEMENTS CONSTRUCTED BY USING THIS PROCEDURE ARE CALLED "MAPPED ELEMENTS". GEOMETRICAL DISCONTINUITIES CREATE SINGULAR FIELDS. FOR THE CONFRONTATION OF SUCH SINGULARITIES, A GRADUAL CONCENTRATION OF THE FINITE ELEMENT MESH IS NEEDED AROUND THE POINT …
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Hierarchical modeling of laminated composite plates using variable kinematic finite elements and mesh superposition
… 2-D, displacement-based, global/local finite element model is developed to permit an accurate, efficient analysis of localized 3-D effects in laminated composite plates. The model is developed using hierarchical, multiple assumed displacement fields at two different levels: (1) at the …
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An Adaptive Mesh Refinement Scheme for Solidification Problems
Methods for adaptive mesh refinement, based on a quadtree data structure, have been developed with the specific objective of tracking a solid/liquid front in a two-dimensional solidification problem. These methods include mesh refinement and unrefinement algorithms for the finite element method …
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Optimization of the metamorphic development process via the genetic algorithm
… still notable, is the use of a non-grid based finite element mesh.</p>
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A variational multiscale a-posteriori error estimation method for nearly incompressible elasticity
… framework for a mixed displacement-pressure finite element method for nearly incompressible elasticity that is based on variational multiscale concepts. The displacement field is decomposed into coarse scales captured by the finite element mesh and fine scales representing the part of the …
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Comparison and results of sheet pile interlock analysis
A finite element program for analyzing the nonlinear behavior of moving contact problems has been developed and used for the analysis of a single sheet pile interlock (Chan and Barker (1985), Wu and Barker (1986). In this study, the program is modified to simulate a sheet pile pull-out test with a …
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Analysis, Modeling, And Simulation Of The Tides In The Loxahatchee River Estuary (Southeastern Florida).
… using a two-dimensional, depth-integrated, finite element-based code for coastal and ocean circulation, ADCIRC-2DDI. Multiple variations of an unstructured, finite element mesh are applied to encompass the Loxahatchee River estuary and different spatial extents of the Atlantic Intracoastal …
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