8.5

9 Immersive Topology Environment for Meshing (ITEM)

The Cubit Geometry and Meshing Toolkit team at Sandia has taken on the ambitious task of reducing the time for simulation by specifically addressing the bottlenecks in the mesh generation process. It is not unusual for the meshing process to take upwards of three-quarters of the entire simulation time. With its many tools developed for a wide range of application areas, it takes time to gain enough proficiency in Cubit to quickly generate a mesh from a complex geometry. As a result, the Immersive Topology Environment for Meshing (ITEM) was developed. ITEM is a user-interactive meshing tool that guides the user through a typical mesh generation process.

With the ultimate goal of reducing the time to generate a mesh for simulation, ITEM has been developed within the Cubit Geometry and Meshing Toolkit to take advantage of its extensive tool suite. Built on top of these tools it attempts to improve the user experience by accomplishing three main tasks:

  1. Guiding the user through the workflow

  2. Providing the user with smart options

  3. Automating geometry and meshing tasks

    9.1  Guiding the user through the workflow.

    9.2  Providing the user with smart options.

    9.3  Automating geometry and meshing tasks.

    9.4 Some ITEM tools found elsewhere in the GUI

    9.5 Generating a Mesh in ITEM

    9.6 Clean Up the Geometry

      9.6.1 Bad geometry representation

      9.6.2 Small details in the model

      9.6.3 Building a Sweepable Topology

        9.6.3.1 Blend Surfaces

        9.6.3.2 Geometry Decomposition

        9.6.3.3 Recognizing Nearly Sweepable Regions

        9.6.3.4 Forced Sweepability

      9.6.4 Resolving Problems with Conformal Assemblies

      9.6.5 Contact Surfaces

      9.6.6 Determining an Appropriate Merge Tolerance

      9.6.7 Determining the Small Feature Size

    9.7 How to Use the ITEM Wizard

    9.8 Defining the Geometric Model

      9.8.1 Geometry Formats

      9.8.2  Creating your own geometry

      9.8.3 Scripting

      9.8.4 CUB Files

      9.8.5 Cubit Files

    9.9 Setting up the Finite Element Model

      9.9.1 Element Shape

      9.9.2 FEA Model Size

    9.10 Validating the Mesh in ITEM