- boundaryThe list of boundary IDs from the mesh where this object applies
C++ Type:std::vector<BoundaryName>
Controllable:No
Description:The list of boundary IDs from the mesh where this object applies
- field_imaginaryImaginary component of field.
C++ Type:std::vector<VariableName>
Controllable:No
Description:Imaginary component of field.
- field_realReal component of field.
C++ Type:std::vector<VariableName>
Controllable:No
Description:Real component of field.
- variableThe name of the variable that this residual object operates on
C++ Type:NonlinearVariableName
Controllable:No
Description:The name of the variable that this residual object operates on
EMRobinBC
First order Robin-style Absorbing/Port BC for scalar variables, assuming plane waves.
Overview
The EMRobinBC object is an implementation of the first-order Robin-style boundary condition outlined in (Jin, 2014) Equation 9.60 and (Jin, 2010) Equation 9.3.51 for scalar field variables.
General (vector field) form
The generic condition from from (Jin, 2014) is, in turn, based on the Sommerfeld radiation condition for scattered fields. Given that any scattered field can be made up of a combination of the scattered field and the incident field (), then we have
where
is the total (i.e., the solution) electric field vector,
is the incoming electric field vector,
is the relative magnetic permeability,
,
is the wave number ( where is the wavelength),
is a radiation condition parameter ( if the condition is applied in free space), and
is the boundary normal vector.
Scalar field form (for EMRobinBC)
In EMRobinBC, this condition is simplified for use with scalar field variables, such as those solved for in plane-wave problems where only a component of the vector field is being solved for. In such a problem, it is assumed that . The choice of as the spatial variable here is arbitrary; the directionality of the plane wave determines the spatial variable of interest. The implemented condition in this object is then
where
is the scalar field component value,
is the wavenumber, and
is a function representing the amplitude profile of the incoming wave.
Note that in EMRobinBC, could be set via the "coeff_real" and "coeff_imag" parameters for a constant wavenumber, or "func_real" and "func_imag" for a property that varies in space or time. The incoming profile is set via "profile_func_real" and "profile_func_imag".
Usage notes
It is important to note that when used as an absorber (strictly absorbing means that mode = absorbing with zero incoming wave but a port also has an absorbing component for any reflections), care must be taken in setting the shape of the truncation boundary as well as the distance from the scattering object. Boundaries as close as away from the object was shown in (Jin, 2014), and several wavelengths were used in the Dipole Antenna Benchmark for VectorEMRobinBC. This boundary condition is also best applied on spherical boundaries (as a result of its origin from the Sommerfeld condition, which was derived for spherical boundaries). Of course, it is also valid on any non-spherical smooth surface with a trade-off in accuracy.
Example Input File Syntax
As a Port
[port_real]
type = EMRobinBC
coeff_real = -0.27706242940220277 # -sqrt(k^2 - (pi/10)^2)
sign = positive
profile_func_real = inc_y
profile_func_imag = 0
field_real = E_real
field_imaginary = E_imag
variable = E_real
component = real
mode = port
boundary = port
[]
As an Absorber
[exit_real]
type = EMRobinBC
coeff_real = 0.27706242940220277
sign = negative
field_real = E_real
field_imaginary = E_imag
variable = E_real
component = real
mode = absorbing
boundary = exit
[]
Input Parameters
- coeff_imag0Constant coefficient, real component.
Default:0
C++ Type:double
Controllable:No
Description:Constant coefficient, real component.
- coeff_real1Constant coefficient, real component.
Default:1
C++ Type:double
Controllable:No
Description:Constant coefficient, real component.
- componentReal or Imaginary wave component.
C++ Type:MooseEnum
Controllable:No
Description:Real or Imaginary wave component.
- displacementsThe displacements
C++ Type:std::vector<VariableName>
Controllable:No
Description:The displacements
- func_imag0Function coefficient, imaginary component.
Default:0
C++ Type:FunctionName
Controllable:No
Description:Function coefficient, imaginary component.
- func_real1Function coefficient, real component.
Default:1
C++ Type:FunctionName
Controllable:No
Description:Function coefficient, real component.
- modeportMode of operation for EMRobinBC. Can be set to 'absorbing' or 'port' (default: 'port').
Default:port
C++ Type:MooseEnum
Controllable:No
Description:Mode of operation for EMRobinBC. Can be set to 'absorbing' or 'port' (default: 'port').
- profile_func_imag0Function coefficient, imaginary component.
Default:0
C++ Type:FunctionName
Controllable:No
Description:Function coefficient, imaginary component.
- profile_func_real1Function coefficient, real component.
Default:1
C++ Type:FunctionName
Controllable:No
Description:Function coefficient, real component.
- prop_getter_suffixAn optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.
C++ Type:MaterialPropertyName
Controllable:No
Description:An optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.
- signpositiveSign of boundary term in weak form.
Default:positive
C++ Type:MooseEnum
Controllable:No
Description:Sign of boundary term in weak form.
Optional Parameters
- absolute_value_vector_tagsThe tags for the vectors this residual object should fill with the absolute value of the residual contribution
C++ Type:std::vector<TagName>
Controllable:No
Description:The tags for the vectors this residual object should fill with the absolute value of the residual contribution
- extra_matrix_tagsThe extra tags for the matrices this Kernel should fill
C++ Type:std::vector<TagName>
Controllable:No
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<TagName>
Controllable:No
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
Controllable:No
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
Controllable:No
Description:The tag for the vectors this Kernel should fill
Tagging Parameters
- control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Controllable:No
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<AuxVariableName>
Controllable:No
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
Controllable:Yes
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
Controllable:No
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<AuxVariableName>
Controllable:No
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
Controllable:No
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
Controllable:No
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.