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.
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.
The challenges of simulation streamlining and automation continue. The need for analysis verification, reviews, quality assurance, pedigree, and archiving are strong. These automation and archival needs can alternate between competing and complementing when determining how to improve the analysis environment and process. The needs compete for priority, resource allocation, and business practice importance. Likewise, implementation strategies of both automation and archival can swing between rather local work groups to more global corporate initiatives. Questions abound about needed connectivity (and the extent of this connectivity) to various CAD systems, product data management (PDM) systems, test data repositories and various information management implementations. This is a complex set of constraints. This presentation will bring focus to this complex environment through sharing experiences. The experiences are those gleaned over years of effort at Sandia to make reasonable sense out of the decisions to be made. It will include a discussion of integration and development of home grown tools for both automation and archival. It will also include an overview of efforts to understand local requirements, compare in-house tools to commercial offerings against those requirements, and options for future progress. Hopefully, sharing this rich set of experiences may prove useful to others struggling to make progress in their own environments.
The generation of all-hexahedral finite element meshes has been an area of ongoing research for the past two decades and remains an open problem. Unconstrained plastering is a new method for generating all-hexahedral finite element meshes on arbitrary volumetric geometries. Starting from an unmeshed volume boundary, unconstrained plastering generates the interior mesh topology without the constraints of a pre-defined boundary mesh. Using advancing fronts, unconstrained plastering forms partially defined hexahedral dual sheets by decomposing the geometry into simple shapes, each of which can be meshed with simple meshing primitives. By breaking from the tradition of previous advancing-front algorithms, which start from pre-meshed boundary surfaces, unconstrained plastering demonstrates that for the tested geometries, high quality, boundary aligned, orientation insensitive, all-hexahedral meshes can be generated automatically without pre-meshing the boundary. Examples are given for meshes from both solid mechanics and geotechnical applications.