# KKSSplitCHCRes

KKS model kernel for the split Bulk Cahn-Hilliard term. This operates on the chemical potential 'c' as the non-linear variable

KKSSplitCHCRes is the split version. In this kernel, we calculate the chemical potential from . The non-linear variable for this Kernel is the concentration . To calculate and , we use the CoupledTimeDerivative and SplitCHWRes kernels, respectively, as described here.

## Residual

In the residual routine we need to calculate the term . We exploit the KKS identity and arbitrarily use the a-phase instead.

(1)

### Jacobian

#### On-Diagonal

Since there is no explicit dependence on the non-linear variable in the residual equation, the diagonal components are zero.

#### Off-diagonal

We are looking for the derivative of , where . We need to apply the chain rule and will again only keep terms with the derivative.

(2)

For

(3)

## Input Parameters

• cbphase concentration corresponding to the non-linear variable of this kernel

C++ Type:std::vector

Description:phase concentration corresponding to the non-linear variable of this kernel

• caphase concentration corresponding to the non-linear variable of this kernel

C++ Type:std::vector

Description:phase concentration corresponding to the non-linear variable of this kernel

• fa_nameBase name of the free energy function F (f_base in the corresponding KKSBaseMaterial)

C++ Type:MaterialPropertyName

Description:Base name of the free energy function F (f_base in the corresponding KKSBaseMaterial)

• wChemical potenial non-linear helper variable for the split solve

C++ Type:std::vector

Description:Chemical potenial non-linear helper variable for the split solve

• variableThe name of the variable that this Kernel operates on

C++ Type:NonlinearVariableName

Description:The name of the variable that this Kernel operates on

• fb_nameBase name of the free energy function F (f_base in the corresponding KKSBaseMaterial)

C++ Type:MaterialPropertyName

Description:Base name of the free energy function F (f_base in the corresponding KKSBaseMaterial)

### Required Parameters

• args_aVector of additional arguments to Fa

C++ Type:std::vector

Description:Vector of additional arguments to Fa

• h_namehBase name for the switching function h(eta)

Default:h

C++ Type:MaterialPropertyName

Description:Base name for the switching function h(eta)

• blockThe list of block ids (SubdomainID) that this object will be applied

C++ Type:std::vector

Description:The list of block ids (SubdomainID) that this object will be applied

### Optional Parameters

• enableTrueSet the enabled status of the MooseObject.

Default:True

C++ Type:bool

Description:Set the enabled status of the MooseObject.

• 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

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.)

• 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.

• 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.

• seed0The seed for the master random number generator

Default:0

C++ Type:unsigned int

Description:The seed for the master random number generator

• 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

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.)

• 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

• 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

• 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

• 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