Preprocessing

CAD system

GiD is a CAD system that features the widely used NURBS surfaces (trimmed or not) for geometry definition. A complete set of tools is provided for quick geometry definition and edition including typical geometrical features such as transformations, intersections or Boolean operations.
preprocess

Meshing

GiD allows the generation of large meshes in a fast and efficient manner for surfaces and volumes. Unstructured, semi-structured, structured, embedded or Cartesian meshes can be generated, as well as 2D and 3D anisotropic meshes (boundary layer).

Several element types are supported (triangles, quadrilaterals, circles, hexahedra, prisms, tetrahedra or spheres) considering also different degree of elements: linear and quadratic. Several mesh editing tools allow users to have full control of any type of mesh. A plug-in system allows incorporating external volume meshers inside GiD.

CAD cleaning & repairing

Several automatic CAD cleaning operations are performed automatically when importing a geometrical CAD model. There are also a handful of graphical tools to detect errors and repair geometries allowing the generation of a proper mesh for the simulation.

Some of the meshers integrated in GiD reduces to the minimum the need of repairing operations and they are able to generate a mesh directly from the imported geometry, even with non-watertight volumes.

Geometry reconstruction

GiD includes tools to convert any surface mesh into a NURBS surfaces representation. This has many advantages when dealing with discrete data as input for the numerical simulation (for example medical images, 3D scanners, etc.), as smooth representation of CAD data, memory savings and access to CAD edition tools.

Assign data to geometry or mesh

Easy assignment of any kind of data to geometry or mesh (boundary conditions, material properties, loads, etc.). Geometrical and mesh entities can be organized in Layers and Groups, where analysis data can be assigned to. This information along with other simulation properties can easily be sent to the solver thanks to GiD’s customization features.

Isogeometric analysis (IGA) support

GiD includes IGA capabilities for modelling, pre- and postprocessing and visualization of results on NURBS based geometries.

  • GiD’s powerful CAD system working with trimmed NURBS surfaces.
  • Exchange NURBS geometries with various formats (IGES, STEP, ACIS …).
  • Graphical assignment of materials, boundary conditions, loads, B-Rep properties, coupling information, etc. directly to the geometry.

Import & export

  • CAD geometrical data can be read in IGES, STEP, Parasolid, ACIS, VDA, DXF, KML (Google Earth), Shapefile and Rhinoceros file formats. Also several cartographical and topographical formats are supported.
  • Following a customized template, all information (mesh and simulation data) is exportable in any format.
  • The geometry export formats are IGES, ACIS, STEP, DXF or Rhino.
  • Mesh data can be read in NASTRAN, STL, VRML, 3DStudio, CGNS, VTK and other formats.

Advanced visualization tools

  • Stereoscopic view: a model can be managed interactively in 3D, and stereoscopic snapshots and animations can be generated.
  • Shadows: providing a better depth perception of the 3D model and a more realistic rendering.
  • Environment reflection: an environment can be defined to be reflected on the model, useful to detect surface imperfections.
  • Mirror and floor effects: a virtual floor can be defined to be used as a mirror, or to project the shadow of the model onto it.

Postprocessing

Several visualization options

Most of the widely used analysis and visualization options for simulations’ results are included in GiD, supporting real and complex numbers. Some examples are contour fill, contour lines, vector plots, isosurfaces, beam diagrams, streamline, ribbons, node tracking, surface extrusions, model deformations, etc.

Each visualization option can be applied either to the original mesh, to an isosurface or to a cut of the mesh. Several visualization options can be applied together at the same time.

GiD also offers the possibility of visualizing and animating the results on several meshes, combining different visualization styles and results.

postprocess

Animations & snapshots

GiD rendered images can be exported in several formats, as well as animations of models or results (also in stereoscopic mode), controlling their resolution. Users can take advantage of advanced external editing tools to create spectacular videos.

Cuts and isosurfaces

Additional surface meshes are generated by GiD for cuts and isosurfaces visualization, and any visualization option of a result can be applied to them. Planar or spherical cuts can be done to visualize the inner parts of the model, and they can follow the deformation of the model.

Import & export

GiD can read simulation result files written in several common formats, such as VTK, TECPLOT or FEMAP. Furthermore, the solver can directly write the results in GiD format using the GiDPost library (provided at no additional cost) to help developers in the adaptation task. GiD native formats are GiD-ASCII, GiD-binary or HDF5-binary. A plug-in mechanism allows other formats to be incorporated into GiD by users or third parties.

Meshes and results can be exported in VTK, VRML, KML and other formats.

Graphs

2D graphs can be plotted with GiD based on the 3D results, allowing the management of different graphs thanks to a user-friendly window. Some examples are: evolution of a result in a point across different time steps (point evolution), line graph, boundary graph and point analysis (a result at a point plotted against another one) and 2D polygonals.

Both cartesian and polar coordinate systems are supported. A logarithmic scale can be set for the axes too. Graphs can also be imported or exported in ASCII format or edited directly in a table.

Handling of large sets of results

Advanced visualization tools, together with the efficient management of data, provide GiD with the capability of visualizing large models with large results files in a fast and user-friendly way.

A memory-cache based system allows handling very large postprocessing files, independently on the physical memory available. Advanced mesh simplification algorithms are used for visualizing huge meshes with results, providing a real-time interaction by the user when managing the model.

Isogeometric analysis (IGA) support

All the extensive visualization and postprocessing tools of GiD are also available for NURBS geometries.

Get access to the complete graphical postprocessing system of GiD just writing a text file, giving the scalar, vector or matrix result on control points of the NURBS.

GiD generates automatically a visualization mesh for visualizing the results: contour fill, vector plots, surface extrusions, model deformations, graphs and animations, etc. Visualization mesh considers geometry details, curvatures, and results gradients.

We are providing the GiDpost library for writing the results in ASCII and binary format.

Advanced visualization tools

  • Stereoscopic view: a model can be managed interactively in 3D, and stereoscopic snapshots and animations can be generated.
  • Shadows: providing a better depth perception of the 3D model and a more realistic rendering.
  • Environment reflection: an environment can be defined to be reflected on the model, useful to detect surface imperfections.
  • Mirror and floor effects: a virtual floor can be defined to be used as a mirror, or to project the shadow of the model onto it.