Mesh_Motion

Syntax

Bc Lumped_Flux For Mass_Balance ([{of} SpeciesName] | [{in} MaterialPhaseName] | [{ls} {a | b | c}]) {@ | at | for | on | over} Mesh Extent Name ([Touching TouchingMeshExtent] | [Opposing OpposingMeshExtent]) = Mesh_Motion [Toggle = toggle]

Summary

Moving boundary condition for Arbitrary Lagrangian-Eulerian (ALE) mesh motion in relative flux form. Accounts for the boundary advective flux due to general mesh motion.

Description

Applies the following boundary flux

- \int q \mathbf{\hat{u}} \cdot \mathbf{n} dS,

where \hat{u} is the mesh velocity and where the integrated scalar q depends on the equation. For the gas phase porous_enthalpy equation with a transported enthalpy = porous, q = \phi \rho_g h_g. Similarly, for the gas phase mass_balance equation, q = \phi \rho_g is the bulk mass density.

This flux boundary condition is automatically applied to the mass balance and porous enthalpy equations when the use relative mass flux porous flow option is turned on.

The following options are present in most boundary conditions/sources. The meaning of each option is as follows:

Toggle

If given, specifies which toggle block controls whether this BC is active or not.

Parameter

Value

Default

{of}

{of | species | subindex}

–

SpeciesName

string

–

{in}

{in | material_phase}

–

MaterialPhaseName

string

–

{ls}

{levelset_phase | ls}

–

Mesh Extent Name

string

–

TouchingMeshExtent

string

–

OpposingMeshExtent

string

–

toggle

“string”

–