- boundaryThe list of boundary IDs from the mesh where this boundary condition applies
C++ Type:std::vector

Description:The list of boundary IDs from the mesh where this boundary condition applies

- variableThe name of the variable that this boundary condition applies to
C++ Type:NonlinearVariableName

Description:The name of the variable that this boundary condition applies to

- velocity_vectorThe components of the velocity vector up to problem dimension
C++ Type:std::vector

Description:The components of the velocity vector up to problem dimension

# AdvectionBC

Boundary conditions for outflow/outflow of advected quantities: phi * velocity * normal, where phi is the advected quantitiy

This boundary condition accounts for advection of a scalar quantity by velocity .

It is usually applied on outflow boundary conditions and originates from integration by parts of . Multiplying by test function and using Green's identity gives: The boundary can be divided into two parts, inflow and outflow satsifying: Boundary conditions are applied on the inflow boundaries, e.g. the value of may be known and is set by a Dirichlet boundary conditions. However, term: still needs to be applied in the PDE. This is covered by AdvectionBC.

## Input Parameters

- displacementsThe displacements
C++ Type:std::vector

Description:The displacements

### Optional Parameters

- control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector

Description:Adds user-defined labels for accessing object parameters via control logic.

- diag_save_inThe name of auxiliary variables to save this BC's diagonal jacobian contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)
C++ Type:std::vector

Description:The name of auxiliary variables to save this BC's diagonal jacobian contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)

- enableTrueSet the enabled status of the MooseObject.
Default:True

C++ Type:bool

Description:Set the enabled status of the MooseObject.

- implicitTrueDetermines whether this object is calculated using an implicit or explicit form
Default:True

C++ Type:bool

Description:Determines whether this object is calculated using an implicit or explicit form

- save_inThe name of auxiliary variables to save this BC's residual contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)
C++ Type:std::vector

Description:The name of auxiliary variables to save this BC's residual contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)

- seed0The seed for the master random number generator
Default:0

C++ Type:unsigned int

Description:The seed for the master random number generator

- use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.
Default:False

C++ Type:bool

Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

### Advanced Parameters

- extra_matrix_tagsThe extra tags for the matrices this Kernel should fill
C++ Type:std::vector

Description:The extra tags for the matrices this Kernel should fill

- extra_vector_tagsThe extra tags for the vectors this Kernel should fill
C++ Type:std::vector

Description:The extra tags for the vectors this Kernel should fill

- matrix_tagssystemThe tag for the matrices this Kernel should fill
Default:system

C++ Type:MultiMooseEnum

Description:The tag for the matrices this Kernel should fill

- vector_tagsnontimeThe tag for the vectors this Kernel should fill
Default:nontime

C++ Type:MultiMooseEnum

Description:The tag for the vectors this Kernel should fill

### Tagging Parameters

## Input Files

- modules/navier_stokes/test/tests/bcs/advection_bc/2d_advection_bc.i
- modules/navier_stokes/test/tests/bcs/advection_bc/advection_bc.i