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CUBIT Geometry and Mesh Generation Toolkit 15.2 User Documentation

Blacker, Ted D.; Owen, Steven J.; Staten, Matthew L.; Quadros, William R.; Hanks, Byron H.; Clark, Brett W.; Meyers, Ray J.; Ernst, Corey E.; Merkley, Karl M.; Morris, Randy M.; McBride, Corey M.; Stimpson, Clinton S.; Plooster, Michael P.; Showman, Sam S.

Welcome to CUBIT, the Sandia National Laboratory automated mesh generation toolkit. CUBIT is a full-featured software toolkit for robust generation of two- and three-dimensional finite element meshes (grids) and geometry preparation. Its main goal is to reduce the time to generate meshes, particularly large hex meshes of complicated, interlocking assemblies. It is a solidmodeler based preprocessor that meshes volumes and surfaces for finite element analysis.

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CUBIT geometry and mesh generation toolkit 15.1 user documentation

Blacker, Ted D.; Owen, Steven J.; Staten, Matthew L.; Quadros, William R.; Hanks, Byron H.; Clark, Brett W.; Meyers, Ray J.; Ernst, Corey E.; Merkley, Karl M.; Morris, Randy M.; McBride, Corey M.; Stimpson, Clinton S.; Plooster, Michael P.; Showman, Sam S.

CUBIT is a full-featured software toolkit for robust generation of two- and three-dimensional finite element meshes (grids) and geometry preparation. Its main goal is to reduce the time to generate meshes, particularly large hex meshes of complicated, interlocking assemblies. It is a solid-modeler based preprocessor that meshes volumes and surfaces for finite element analysis. Mesh generation algorithms include quadrilateral and triangular paving, 2D and 3D mapping, hex sweeping and multi-sweeping, tetrahedral meshing, and various special purpose primitives. CUBIT contains many algorithms for controlling and automating much of the meshing process, such as automatic scheme selection, interval matching, sweep grouping, and also includes state-of-the-art smoothing algorithms.

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Mesh Scaling for Affordable Solution Verification

Procedia Engineering

Staten, Matthew L.; Carnes, Brian C.; McBride, Corey; Stimpson, Clint; Cox, James C.

Solution verification is the process of verifying the solution of a finite element analysis by performing a series of analyses on meshes of increasing mesh densities, to determine if the solution is converging. Solution verification has historically been too expensive, relying upon refinement templates resulting in an 8X multiplier in the number of elements. For even simple convergence studies, the 8X and 64X meshes must be solved, quickly exhausting computational resources. In this paper, we introduce Mesh Scaling, a new global mesh refinement technique for building series of all-hexahedral meshes for solution verification, without the 8X multiplier. Mesh Scaling reverse engineers the block decomposition of existing all-hexahedral meshes followed by remeshing the block decomposition using the original mesh as the sizing function multiplied by any positive floating number (e.g. 0.5X, 2X, 4X, 6X, etc.), enabling larger series of meshes to be constructed with fewer elements, making solution verification tractable.

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Parallel octree-based hexahedral mesh generation for eulerian to lagrangian conversion

Owen, Steven J.; Staten, Matthew L.

Computational simulation must often be performed on domains where materials are represented as scalar quantities or volume fractions at cell centers of an octree-based grid. Common examples include bio-medical, geotechnical or shock physics calculations where interface boundaries are represented only as discrete statistical approximations. In this work, we introduce new methods for generating Lagrangian computational meshes from Eulerian-based data. We focus specifically on shock physics problems that are relevant to ASC codes such as CTH and Alegra. New procedures for generating all-hexahedral finite element meshes from volume fraction data are introduced. A new primal-contouring approach is introduced for defining a geometric domain. New methods for refinement, node smoothing, resolving non-manifold conditions and defining geometry are also introduced as well as an extension of the algorithm to handle tetrahedral meshes. We also describe new scalable MPI-based implementations of these procedures. We describe a new software module, Sculptor, which has been developed for use as an embedded component of CTH. We also describe its interface and its use within the mesh generation code, CUBIT. Several examples are shown to illustrate the capabilities of Sculptor.

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A comparison of mesh morphing methods for shape optimization

Owen, Steven J.; Staten, Matthew L.

The ability to automatically morph an existing mesh to conform to geometry modifications is a necessary capability to enable rapid prototyping of design variations. This paper compares six methods for morphing hexahedral and tetrahedral meshes, including the previously published FEMWARP and LBWARP methods as well as four new methods. Element quality and performance results show that different methods are superior on different models. We recommend that designers of applications that use mesh morphing consider both the FEMWARP and a linear simplex based method.

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A methodology for quadrilateral finite element mesh coarsening

Engineering with Computers

Staten, Matthew L.

High fidelity finite element modeling of continuum mechanics problems often requires using all quadrilateral or all hexahedral meshes. The efficiency of such models is often dependent upon the ability to adapt a mesh to the physics of the phenomena. Adapting a mesh requires the ability to both refine and/or coarsen the mesh. The algorithms available to refine and coarsen triangular and tetrahedral meshes are very robust and efficient. However, the ability to locally and conformally refine or coarsen all quadrilateral and all hexahedral meshes presents many difficulties. Some research has been done on localized conformal refinement of quadrilateral and hexahedral meshes. However, little work has been done on localized conformal coarsening of quadrilateral and hexahedral meshes. A general method which provides both localized conformal coarsening and refinement for quadrilateral meshes is presented in this paper. This method is based on restructuring the mesh with simplex manipulations to the dual of the mesh. Finally, this method appears to be extensible to hexahedral meshes in three dimensions.

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Unconstrained paving & plastering: A new idea for all hexahedral mesh generation

Proceedings of the 14th International Meshing Roundtable, IMR 2005

Staten, Matthew L.; Owen, Steven J.; Blacker, Ted D.

Unconstrained Plastering is a new algorithm with the goal of generating a conformal all-hexahedral mesh on any solid geometry assembly. Paving[1] has proven reliable for quadrilateral meshing on arbitrary surfaces. However, the 3D corollary, Plastering [2][3][4][5], is unable to resolve the unmeshed center voids due to being over-constrained by a pre-existing boundary mesh. Unconstrained Plastering attempts to leverage the benefits of Paving and Plastering, without the over-constrained nature of Plastering. Unconstrained Plastering uses advancing fronts to inwardly project unconstrained hexahedral layers from an unmeshed boundary. Only when three layers cross, is a hex element formed. Resolving the final voids is easier since closely spaced, randomly oriented quadrilaterals do not over-constrain the problem. Implementation has begun on Unconstrained Plastering, however, proof of its reliability is still forthcoming. © 2005 Springer-Verlag Berlin Heidelberg.

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55 Results
55 Results