You can create an Eulerian boundary condition to control the flow of materials into and out of an Eulerian region. Eulerian boundary conditions should be applied only to parts with an Eulerian section assignment, and they cannot be applied in the initial step of an analysis.
To specify an Eulerian boundary condition:
Display the Eulerian boundary condition editor using one of the following methods:
To create a new Eulerian boundary condition, follow the procedure outlined in “Creating boundary conditions,” Section 16.8.2 (Category: Other; Types for Selected Step: Eulerian boundary).
To edit an existing Eulerian boundary condition using menus or managers, see “Editing step-dependent objects,” Section 3.4.13. To edit the region to which the boundary condition is applied, see “Editing the region to which a prescribed condition is applied,” Section 16.8.4.
Specify the Flow type that the boundary condition will control:
Inflow controls the flow of Eulerian material into the region across the selected surface.
Outflow controls the flow of Eulerian material out of the region across the selected surface.
Both allows you to specify controls for inflow and outflow conditions in the same boundary condition definition.
If you selected Inflow (or Both) as the Flow type, select the Inflow condition:
Select Free to allow any new material to flow freely into the Eulerian region. The material that flows into the region is based on the material that currently occupies the region: as Eulerian material inside the region moves away from the boundary surface, the same material flows across the boundary to replace it.
Select None to prevent inflow of any new Eulerian material (including void) across the boundary surface. Eulerian material inside the region can move tangentially along the boundary surface, but it cannot separate from the boundary surface.
Select Void to allow only void to flow into the Eulerian region. As Eulerian material inside the region moves away from the boundary surface, void flows across the boundary to replace it.
If you selected Outflow (or Both) as the Flow type, select the Outflow condition:
Select Zero pressure to allow material to flow out of the Eulerian region while also enforcing a condition of zero net pressure across the boundary surface using artificial traction forces.
Select Free to allow material to flow freely out of the Eulerian region without any artificial traction forces.
Select Nonreflecting to allow material to flow out of the Eulerian region while also minimizing the reflection of dilatational and shear wave energy back into the region using artificial traction forces.
Select Equilibrium to allow material to flow out of the Eulerian region while also enforcing a condition of zero-order continuous stress across the boundary surface using artificial traction forces.
