Creating Overset Interfaces

An overset mesh interface couples one overset region with the background region or another overset region.

To create overset interfaces, you have the two following options:
  • Overset Mesh Interface

    Use this type of overset mesh interface for any overset mesh simulation except for a zero gap configuration.

    There are two options for creating region overset mesh interfaces:
    • Single Interface Creation through pairwise (=2) region selection.
    • Multiple Interface Creation through multiple (>2) region selection.

    Depending on how you select the regions, do one of the following:

    Region Selection Steps
    Pairwise (=2)
    1. Use <Ctrl><Click> to select two regions (one overset region and one background region or two overset regions).
    2. Right-click on the selected regions and choose Create Interface > Overset Mesh.
    3. Select the Interfaces > Overset Mesh 1 node and set the Overset Mesh Interface Properties.
    Multiple (>2)
    1. Use <Ctrl><Click> to select all the relevant regions for overset interfaces (including the background region).
    2. To create multiple overset interfaces, do one of the following:
      • Right-click on the selected regions and choose Create Interface > Overset Mesh (Multi-level) to create interfaces between each region combination.
      • Right-click on the selected regions and choose Create Interface > Overset Mesh (Two-level) to create interfaces between each non-background region and the background region.
    3. Expand the Interface node and set the Overset Mesh Interface Properties for all the overset interfaces.
  • You have two options for creating region overset mesh zero gap interfaces, see also Overset Mesh Interfaces:
    • Single Interface Creation through pairwise region selection.
    • Multiple Interface Creation through multiple region selection.
    Region Selection Steps
    Pairwise (=2)
    1. Use <Ctrl><Click> to select two regions (one overset region and one background region or two overset regions).
    2. Right-click on the selected regions and choose Create Interface > Overset Mesh ZeroGap.
    3. Select the Interfaces > Overset Mesh ZeroGap 1 node and set the Overset Mesh Interface Properties.
    4. (Optional) Select the Boundaries > Number of Zero Gap Layers node and set the Number of Zero Gap Layers Properties.
      NoteFor a given mesh resolution in the gap, this option lets you change the width of the gap. The cells in the gap are deactivated and flow through it is prevented.

    A ZeroGapWall boundary and Number of Zero Gap Layers node are added under each Boundaries node. An Overset Mesh ZeroGap 1 node is added under the Interfaces node.

    Multiple (>2)
    1. Use <Ctrl><Click> to select all the relevant regions for overset interfaces.
    2. To create multiple overset interfaces, do one of the following:
      • Right-click on the selected regions and choose Create Interface > Overset Mesh ZeroGap (Multi-level) to create interfaces between each region combination.
      • Right-click on the selected regions and choose Create Interface > Overset Mesh ZeroGap (Two-level) to create interfaces between each non-background region and the background region.
    3. Expand the Interfaces node and set the Overset Mesh Interface Properties for all the overset ZeroGap interfaces.
In the case of multiple overset interfaces, you can control the order in which the hole-cutting process uses regions by:
  • Swapping region assignments on a single interface. To achieve this you right-click overset interface and select Swap Region.
  • Reordering regions priority in the Overset Hierarchy manager.
To change the current Overset Hierarchy:
  1. Select the Interfaces node and open the Overset Hierarchy manager by clicking on the right of it property.


  2. Select one region on the list and move up its order.