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Showing 1 to 19 of 19 for “"mesh quality"”.
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Elastic Mesh Deformation for Internal Flows with Moving Boundaries
This project aims to study elastic-based mesh deformation for internal flow problems with obstructions. As such a tank with a flexible internal beam serves as the tested case employed in this work. As such a computer code was developed and the elastic deformation was implemented via the Finite …
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Code Verification and Numerical Accuracy Assessment for Finite Volume CFD Codes
… verification testing is performed on different mesh types which include triangular and quadrilateral elements in 2D and tetrahedral, prismatic, and hexahedral elements in 3D. The requirements of systematic mesh refinement are discussed, particularly in regards to unstructured meshes. Different …
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Linear elastic mesh deformation via localized orthotropic material properties optimized by the adjoint method
… proven difficult due to conforming higher-order meshes to curved geometries. If higher-order nodes are not placed on the surface of the geometry error is introduced into the simulated solution. This barrier is largely a non-issue for inviscid meshes where a mid-edge node can be projected onto the …
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Tetrahedral Mesh Improvement, Algorithms and Experiments
… of slivers in large three-dimensional Delaunay meshes has been reported as early as 1985. They persist even after treatment with the Delaunay refinement algorithm. Cheng et al. proposed to remove slivers by assigning real weights to the points and change the Delaunay to the weighted Delaunay …
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Automatic higher order mesh generation and movement utilizing spring-field and vector-adding
… geometry applicable, unstructured curved 2D mesh generation method is developed. Based on this 2D method, an extension to 3D geometries is developed. The methodology of this mesh generation is to provide near-body and off-body meshes by an advancing-layer method to avoid mesh quality problems …
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Numerical simulation of nonlinear response of moored floating structures to steep waves
… and the conventional FEM is that the complex mesh is generated only once at the beginning of the calculation and is moved at all other time steps in order to conform to the motion of the free surface and structures. This feature allows one to use an unstructured mesh with any degree of …
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Sonic boom prediction methods using feature-based adaptation of unstructured meshes
… uses P_HUGG, a parallel hierarchical Cartesian mesh generation algorithm to generate a volume mesh, with the solution-based mesh adaptation capability of P_HUGG being exploited. The mesh quality was improved using P_OPT, a parallel optimization-based mesh-smoothing program. In the second method, …
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Automated Quadrilateral Coarsening by Ring Collapse
In most finite element analysis, a uniform mesh is not the optimum way to model the problem. Mesh adaptation is the ability to modify a finite element model to include regions of the mesh with higher and lower node density. Mesh adaptation has received extensive study in both computational …
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Surpassing Local Optimality in Geometry Processing
… programming to target cross-field based quad meshing, hexahedral mesh quality enhancement, and algebraic collision detection. With these tools, we manage to avoid shallower local minima and sometimes to reach or even surpass globally optimal solutions. We conclude with some principles by which …
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Generation of high quality 2D meshes for given bathymetry
… and applies a procedure to generate high quality 2D meshes for any given ocean region with complex coastlines. The different criteria used in determining mesh element sizes for a given domain are discussed, especially sizing criteria that depend on local properties of the bathymetry and …
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Multiphysics modelling of geometrically-complex flow metering devices
… to code and negates the use of specialised mesh generation or mesh-quality optimisation techniques. This method was implemented within an existing software framework (AMReX) which solves the governing partial differential equations for the flow while also including the capability for …
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All Hexahedral Meshing of Multiple Source, Multiple Target, Multiple Axis Geometries Via Automatic Grafting and Sweeping
… for the automatic creation of finite element meshes composed entirely of hexahedra (all-hex) is an active area of research. All-hex meshes are desirable for their characteristic of high accuracy with a low node count. Sweeping is one of the most widely used algorithms for generating all-hex …
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Intervenciones multimodales enfocadas en la percepción de la calidad de vida de personas mayores con enfermedad de alzheimer: una revisión de alcance
… EBSCO. Seguido, se determinó los términos DeSC y MeSH: Quality of Life, Alzheimer Disease Disease y en el descriptor DeCS: Calidad de Vida, Enfermedad de Alzheimer. La selección de evidencia se clasificó en extracción por medio del Software Zotero® y la selección por medio del software Rayyan®. …
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Unsteady Wetness Effects in Low Pressure Steam Turbines
… early stage of development and improvements in mesh quality and boundary and interface treatments will be required before firm conclusions can be drawn.
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An Approximation for the Twenty-One-Moment Maximum-Entropy Model of Rarefied Gas Dynamics
… accuracy as well as a decreased sensitivity to mesh quality. Unfortunately, higher-order maximum-entropy closures cannot be expressed in closed form. The only known affordable option is to propose approximations. Previous approximations to the fourteen-moment maximum-entropy model have been …
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Multigrid methods for complex engineering geometries and unstructured meshes
… methods decays significantly if locally poor quality cells are present, and it is found that the poor convergence is due to the local failure of the smoothing property. The high frequency error localised in regions of low quality cells is not eliminated by standard multigrid smoothers and …
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Spectral element mesh generation and improvement methods
Made available in DSpace on 2017-03-01T16:37:06Z (GMT). No. of bitstreams: 2 MITTAL-THESIS-2016.pdf: 6322867 bytes, checksum: ceeadf110747990a0a9d8d4edfd97f89 (MD5) LICENSE.txt: 4209 bytes, checksum: e320f9ba4f501ad2c60568d7212152e0 (MD5) Previous issue date: 2016-12-06
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Well balanced Arbitrary-Lagrangian-Eulerian Finite Volume schemes on moving nonconforming meshes for non-conservative Hyperbolic systems
… control volumes. In order to avoid the typical mesh distortion caused by shear flows in Lagrangian-type methods, we adopt a nonconforming treatment of sliding interfaces, which requires the dynamical insertion or deletion of nodes and edges, and produces hanging nodes and space-time faces shared …
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Size Function Based Mesh Relaxation
… 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 methods.</p>