# NormalMortarLMMechanicalContact

Similar to the NormalNodalLMMechanicalContact object except the constraints are enforced in an integral way via the mortar method as opposed to pointwise at nodes. Some numerical experiments suggest that the integral method of enforcing normal contact constraints displays worse non-linear convergence than the pointwise method.

Enforces the normal contact complementarity conditions in a mortar discretization

## Input Parameters

• primary_boundaryThe name of the primary boundary sideset.

C++ Type:BoundaryName

Options:

Description:The name of the primary boundary sideset.

• primary_subdomainThe name of the primary subdomain.

C++ Type:SubdomainName

Options:

Description:The name of the primary subdomain.

• secondary_boundaryThe name of the secondary boundary sideset.

C++ Type:BoundaryName

Options:

Description:The name of the secondary boundary sideset.

• secondary_subdomainThe name of the secondary subdomain.

C++ Type:SubdomainName

Options:

Description:The name of the secondary subdomain.

### Required Parameters

• compute_lm_residualsTrueWhether to compute Lagrange Multiplier residuals

Default:True

C++ Type:bool

Options:

Description:Whether to compute Lagrange Multiplier residuals

• compute_primal_residualsTrueWhether to compute residuals for the primal variable.

Default:True

C++ Type:bool

Options:

Description:Whether to compute residuals for the primal variable.

• execute_onLINEARThe list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM.

Default:LINEAR

C++ Type:ExecFlagEnum

Options:NONE INITIAL LINEAR NONLINEAR TIMESTEP_END TIMESTEP_BEGIN FINAL CUSTOM

Description:The list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM.

• ncp_function_typeminThe type of the nonlinear complimentarity function; options are min or fb where fb stands for Fischer-Burmeister

Default:min

C++ Type:MooseEnum

Options:min fb

Description:The type of the nonlinear complimentarity function; options are min or fb where fb stands for Fischer-Burmeister

• periodicFalseWhether this constraint is going to be used to enforce a periodic condition. This has the effect of changing the normals vector for projection from outward to inward facing

Default:False

C++ Type:bool

Options:

Description:Whether this constraint is going to be used to enforce a periodic condition. This has the effect of changing the normals vector for projection from outward to inward facing

• primary_disp_yThe y displacement variable on the primary face

C++ Type:NonlinearVariableName

Options:

Description:The y displacement variable on the primary face

• primary_variablePrimal variable on primary surface. If this parameter is not provided then the primary variable will be initialized to the secondary variable

C++ Type:VariableName

Options:

Description:Primal variable on primary surface. If this parameter is not provided then the primary variable will be initialized to the secondary variable

• secondary_disp_yThe y displacement variable on the secondary face

C++ Type:NonlinearVariableName

Options:

Description:The y displacement variable on the secondary face

• secondary_variablePrimal variable on secondary surface.

C++ Type:VariableName

Options:

Description:Primal variable on secondary surface.

• variableThe name of the lagrange multiplier variable that this constraint is applied to. This parameter may not be supplied in the case of using penalty methods for example

C++ Type:NonlinearVariableName

Options:

Description:The name of the lagrange multiplier variable that this constraint is applied to. This parameter may not be supplied in the case of using penalty methods for example

### Optional Parameters

• control_tagsAdds user-defined labels for accessing object parameters via control logic.

C++ Type:std::vector

Options:

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

• enableTrueSet the enabled status of the MooseObject.

Default:True

C++ Type:bool

Options:

Description:Set the enabled status of the MooseObject.

• 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

Options:

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.

• extra_matrix_tagsThe extra tags for the matrices this Kernel should fill

C++ Type:std::vector

Options:

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

Options:

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

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

Description:The tag for the vectors this Kernel should fill