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  • Set up your own cloud-native simulation in minutes.

    • Documentation

    SimScale DocumentationSimulation SetupBoundary ConditionsEmpty 2D

    Empty 2D

    The Empty 2D boundary condition is used in reduced dimension cases. This allows performing a two-dimensional CFD simulation on a three-dimensional model which has been extruded in the direction normal to the flow.

    The Empty 2D boundary condition should be applied on both boundary faces which are normal to the reduced coordinate direction, i.e., the faces coplanar with the flow.

    The settings panel in SimScale looks as follows:

    empty 2d boundary condition window in simscale
    Figure 1: Empty 2D boundary condition set up in SimScale Workbench

    Important

    This boundary condition only works for u003ca href=u0022https://www.simscale.com/docs/simulation-setup/meshing/mesh-upload/u0022u003euploaded meshesu003c/au003e. Moreover, the uploaded mesh should have a one cell thickness in the reduced coordinate direction.

    As an example, in the figure below, by specifying an empty 2D boundary condition on the two faces highlighted in blue, the y-direction won’t be solved during the simulation.

    empty 2d bc
    Figure 2: External aerodynamics case. By defining an empty 2D condition to the highlighted faces, the direction normal to the assignments is no longer solved.

    Notice that the reduced dimension (y in this case) is only one cell thick signifying a 2 Dimensional mesh in the xy-plane.

    Validation Case: Rising Bubble

    Last updated: February 28th, 2025