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Showing 1 to 14 of 14 for “"Mesh optimization"”.
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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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Tetrahedral mesh optimization and generation via topological transformations and gradient based node perturbation
A general tetrahedral mesh optimization scheme utilizing both topological changes (i.e. flips) and gradient-based vertex optimization (i.e. smoothing) is demonstrated. This scheme is used in the optimization of tetrahedral meshes created by third-party software as well as a grid generation …
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Provably convergent anisotropic output-based adaptation for continuous finite element discretizations
… error estimation combined with metric-based mesh adaptivity provides a powerful means of quantifiably controlling the error in these simulations, for output quantities of interest to engineers and scientists. The Mesh Optimization via Error Sampling and Synthesis (MOESS) algorithm, developed …
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An adaptive space-time discontinuous Galerkin method for reservoir flows
… on a fully unstructured space-time mesh, instead of a conventional time-marching approach. Anisotropic mesh adaptation is performed to reduce the error of a specified output of interest, by using a posteriori error estimates from the dual weighted residual method to drive a …
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A space-time adaptive method for flows in oil reservoirs
… requires the generation of (d+1)-dimensional meshes, where time is treated as an additional spatial dimension. Anisotropic mesh adaptation is performed based on a posteriori error estimation to reduce the error of a specified output of interest. This work makes use of the DWR method for error …
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On the Application of an Output-based Adaptive, Higher-order Finite Element Method to Sonic Boom Propagation
… error estimation, which in turns drives the mesh optimization process. The method’s efficacy is validated using smooth solutions for the viscous Burgers equation and the adjoint PDE for a volume output functional. Additionally, artificial viscosity is incorporated via a shock sensor PDE …
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Generation and Optimization of Quadrilateral and Hexahedral Meshes
Structured quadrilateral (quad) meshes are preferred in many engineering and medical applications due to their desired numerical properties. Despite the extensive research, automatic generation of quad- and hex- meshes with optimal structure remains a challenge. In-lieu-of generating a quad-mesh …
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An adaptive variational multiscale method with discontinuous subscales for aerodynamic flows
… simulation of aerodynamic flows is output-based mesh adaptation, which optimizes a mesh to minimize the discretization error in an output of interest. The state of the art in output-based adaptation uses the discontinuous Galerkin (DG) method, which is computationally expensive due to its …
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Unsteady adjoint analysis for output sensitivity and mesh adaptation
… fluid dynamics (CFD) has been applied to design optimization and mesh adaptation, but due to the relative expense of unsteady analysis these applications have predominantly been for steady problems. As the use of adjoint methods continues to becomes more prevalent, more problems are encountered …
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Truncation Error Based Mesh Adaptation and its Application to Multi-Mesh CFD
… error in a simulation is by performing mesh adaptation. In this work, the mesh adaptation processes are driven by the truncation error, which is the local source of the discretization error. Because this work is focused on methods for structured grids, r-adaptation is used as opposed to …
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Highly scalable solution of incompressible Navier-Stokes equations using the spectral element method with overlapping grids
… SEM framework. This dissertation also presents a mesh optimizer that has been specifically designed for meshes generated for turbulent flow problems. The optimizer supports surface mesh improvement, which minimizes geometrical approximation errors. The smoother is shown to reduce the computational …
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Finite Element Modeling Driven by Health Care and Aerospace Applications
… analysis, and computer implementation of mesh generation algorithms encountered in finite element modeling in health care and aerospace. The finite element method can reduce a continuous system to a discrete idealization that can be solved in the same manner as a discrete system, provided …
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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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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>