Defining a Resampled Volume

Volume rendering is used to display (semitransparent) volumetric objects that are defined in a 3D domain. If your graphics card does not support volume rendering, activate advanced rendering for the relevant scene.

The resampling process generates an approximation of the result values that reside in the underlying 3D finite volume region. Each finite volume cell is approximated with cubic voxel cells. The data from the volume cell is stored in the vertices of the structured voxel mesh. The voxel mesh itself is organized in an octree data structure. When investigating positions between voxel vertices the value is interpolated based on the neighboring vertex values. For each position in the 3D domain, color and opacity values are specified.

To create a resampled volume:
  1. Follow the general procedure outlined in the section, Defining Derived Parts General Workflow. Choose the menu option, New Part > Resampled Volume....
  2. Specify the input parts and display option as described in the section, Defining Derived Parts General Workflow. The resampled volume part can be rendered only in the scalar displayer.
  3. Specify the dimensions and position of the bounding box by setting the following properties, in either the in-place dialog or the Properties window:
    • Origin
    • Size
    • Rotation Axis
    • Rotation Angle

    When using the in-place dialog, you can activate Snap to part to position the bounding box along a part. This feature is available when the resampled volume tool is active. See Using the Resampled Volume Tool.

  4. To reduce processing costs, always minimize the number of voxels created by the resampled volume. To control this number, set the following properties:
    • Cell Size to Voxel Ratio
    • Refinement Metric
    • Minimum Voxel Size
    For more information, see Resampled Volume Properties.

    When using the in-place dialog, you can click Preview to get a graphical preview of the resampled volume and a preliminary estimate of the number of voxels.

  5. To use the resampled volume in a scalar scene:
    1. Add the resampled volume part to the Parts node of the target scalar displayer.
    2. Select the [scalar displayer] and set Representation to Volume Mesh or Latest Surface/Volume Mesh. You can also use the resampled volume with a solution view representation.
When you add a resampled volume part to a scalar displayer, that displayer acquires a new sub-node, Resampled Volume Settings. This node allows you to choose a rendering mode, activate the lighting mode, and specify accuracy:
  1. Set the properties of the Resampled Volume Settings node to control how the data is displayed.

    In particular, the Plane Section rendering mode lets you view the size of individual voxels that are used to resample a field.

    For more information on the available properties, see Resampled Volume Properties.

Once you have finished creating a resampled volume part, you can rotate and zoom in the display to get a clear view of the resampled volume. If you did not assign the part to the current scene, you can drag and drop its node into the visualization display. The resampled volume part can be rendered only in the scalar displayer.
NoteWhen preparing a scene for Simcenter STAR-CCM+ Virtual Reality in which you intend to release particles interactively, add a resampled volume to a vector displayer. The scene display in Simcenter STAR-CCM+ indicates the inclusion of the resampled volume by rendering its bounding box with lines.