FEM ConstraintFlowVelocity

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Revision as of 04:58, 20 March 2023 by Uwestoehr (talk | contribs) (updates and wording)

FEM ConstraintFlowVelocity

Menu location
Model → Fluid Constraints → Constraint flow velocity
Workbenches
FEM
Default shortcut
None
Introduced in version
-
See also
FEM Constraint initial flow velocity

Description

Applies a flow velocity as boundary condition to an edge in 2D or to a face in 3D.

Constraint flow velocity menus within the task panel

Usage

  1. There are several ways to invoke the command:
    • Press the FEM ConstraintFlowVelocity button.
    • Select the Model → Fluid Constraints → Constraint flow velocity option from the menu.
  2. The task panel will display menus for constraint flow velocity
  3. Select the target Edges or Faces.
  4. Press the Add button.
  5. Deselect "unspecified" to activate the necessary fields for edition.
  6. Fill in the values in mm/s for the main Cartesian components.

Notes

  • Any vector component that should be the result of the solver must be set as Unspecified.
  • If the target face or edge is not aligned with the main Cartesian coordinate system, it is possible to set the option Normal to boundary.
    If Normal to boundary is checked, the normal vector to the selected edge or face is X and it will be oriented away from the mesh domain.
    For example, if a flow of 20 mm/s of air should enter the domain, then with Normal to boundary one must input -20 mm/s in the Velocity x field.
  • For a wall with non-slip condition, set all velocity components to 0.
  • For a symmetry condition, set the the flow to 0, Unspecified, Unspecified) if Normal to boundary is checked.