KKSMultiACBulkC

Multi-phase KKS model kernel (part 2 of 2) for the Bulk Allen-Cahn. This includes all terms dependent on chemical potential.

Residual

For the 3-phase KKS model, if the non-linear variable is ,

where is the phase concentration for phase and is the interpolation function for phase defined in Folch and Plapp (2005) (referred to as there, but we use to maintain consistency with other interpolation functions in MOOSE). Since in the KKS model, chemical potentials are constrained to be equal at each position, .

Jacobian

On-diagonal

If the non-linear variable is , the on-diagonal Jacobian is

Off-diagonal: Phase Concentrations

Since appears in the residual, the off-diagonal Jacobian for is a little more complicated than for or . For , and similarly for . then , and are handled first in the code. For the off-diagonal Jacobians we also need to multiply by , the Allen-Cahn mobility.

Off-diagonal: Other Coupled Variables

If the non-linear variable is , the off-diagonal Jacobian for is and similar for .

For any other coupled variables, for example temperature

What's implemented in the code for the off-diagonal Jacobian for , and any other coupled variables such as is the generalization for the above two equations for non-linear variable : (This handles everything except for , , , which are handled separately first). For the off-diagonal Jacobians we also need to multiply by , the Allen-Cahn mobility.

Input Parameters

  • Fj_namesList of free energies for each phase. Place in same order as hj_names!

    C++ Type:std::vector<MaterialPropertyName>

    Controllable:No

    Description:List of free energies for each phase. Place in same order as hj_names!

  • cj_namesArray of phase concentrations cj. Place in same order as Fj_names!

    C++ Type:std::vector<VariableName>

    Controllable:No

    Description:Array of phase concentrations cj. Place in same order as Fj_names!

  • eta_iOrder parameter that derivatives are taken with respect to

    C++ Type:std::vector<VariableName>

    Controllable:No

    Description:Order parameter that derivatives are taken with respect to

  • hj_namesSwitching Function Materials that provide h. Place in same order as Fj_names!

    C++ Type:std::vector<MaterialPropertyName>

    Controllable:No

    Description:Switching Function Materials that provide h. Place in same order as Fj_names!

  • 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

Required Parameters

  • blockThe list of blocks (ids or names) that this object will be applied

    C++ Type:std::vector<SubdomainName>

    Controllable:No

    Description:The list of blocks (ids or names) that this object will be applied

  • coupled_variablesVector of nonlinear variable arguments this object depends on

    C++ Type:std::vector<VariableName>

    Controllable:No

    Description:Vector of nonlinear variable arguments this object depends on

  • displacementsThe displacements

    C++ Type:std::vector<VariableName>

    Controllable:No

    Description:The displacements

  • mob_nameLThe mobility used with the kernel

    Default:L

    C++ Type:MaterialPropertyName

    Controllable:No

    Description:The mobility used with the kernel

  • 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.

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

    Options:nontime, system

    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

    Options:nontime, time

    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 Kernel'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 Kernel'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 Kernel'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 Kernel'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.

Advanced Parameters

References

  1. R. Folch and M. Plapp. Quantitative phase-field modeling of two-phase growth. Phys. Rev. E, 72:011602, Jul 2005. URL: https://link.aps.org/doi/10.1103/PhysRevE.72.011602, doi:10.1103/PhysRevE.72.011602.[BibTeX]