# Compute R-Spherical Finite Strain

Compute a strain increment and rotation increment for finite strains in 1D spherical symmetry problems.

## Description

The material ComputeRSphericalFiniteStrain calculates the small incremental strain for 1D R-Spherical systems.

The 1D RSpherical materials and kernel are designed to model sphere geometries with 1D models. Symmetry in the polar () and azimuthal () directions is assumed, and the model is considered to revolve in both of these directions. In the 1D R-Spherical code, the material properties, variables (e.g. temperature), and loading conditions are all assumed to be spherically symmetric: these attributes only depend on the axial position.

note

The COORD_TYPE in the Problem block of the input file must be set to RSPHERICAL.

As in the plane strain and axisymmetric cases, the stress and strain tensors are modified in the spherical problem; only the diagonal components are non-zero in this 1D problem. (1) where the value of the normal strain components in the polar and azimuth directions and depends on the displacement and position in the radial direction (2) Although axisymmetric problems solve for 3D stress and strain fields, the problem is mathematically 1D. In the cylindrical coordinate axisymmetric system, the values of stress and strain in the and directions do not depend on the or coordinates.

Once the deformation gradient is calculated for the 1D geometry, the deformation gradient is passed to the strain and rotation methods used by default 3D Cartesian simulations, as described in the Finite Strain Class page.

## Example Input File Syntax

The finite incremental R-spherical strain calculator can be activated in the input file through the use of the TensorMechanics Master Action, as shown below.


[Modules/TensorMechanics/Master]
[./all]
strain = FINITE
[../]
[]
(modules/tensor_mechanics/test/tests/1D_spherical/finiteStrain_1DSphere_hollow.i)
note:Use of the Tensor Mechanics Master Action Recommended

The TensorMechanics Master Action is designed to automatically determine and set the strain and stress divergence parameters correctly for the selected strain formulation. We recommend that users employ the TensorMechanics Master Action whenever possible to ensure consistency between the test function gradients and the strain formulation selected.

## Input Parameters

• displacementsThe displacements appropriate for the simulation geometry and coordinate system

C++ Type:std::vector

Options:

Description:The displacements appropriate for the simulation geometry and coordinate system

### Required Parameters

• global_strainOptional material property holding a global strain tensor applied to the mesh as a whole

C++ Type:MaterialPropertyName

Options:

Description:Optional material property holding a global strain tensor applied to the mesh as a whole

• decomposition_methodTaylorExpansionMethods to calculate the strain and rotation increments

Default:TaylorExpansion

C++ Type:MooseEnum

Options:TaylorExpansion EigenSolution

Description:Methods to calculate the strain and rotation increments

• computeTrueWhen false, MOOSE will not call compute methods on this material. The user must call computeProperties() after retrieving the Material via MaterialPropertyInterface::getMaterial(). Non-computed Materials are not sorted for dependencies.

Default:True

C++ Type:bool

Options:

Description:When false, MOOSE will not call compute methods on this material. The user must call computeProperties() after retrieving the Material via MaterialPropertyInterface::getMaterial(). Non-computed Materials are not sorted for dependencies.

• base_nameOptional parameter that allows the user to define multiple mechanics material systems on the same block, i.e. for multiple phases

C++ Type:std::string

Options:

Description:Optional parameter that allows the user to define multiple mechanics material systems on the same block, i.e. for multiple phases

• eigenstrain_namesList of eigenstrains to be applied in this strain calculation

C++ Type:std::vector

Options:

Description:List of eigenstrains to be applied in this strain calculation

• volumetric_locking_correctionFalseFlag to correct volumetric locking

Default:False

C++ Type:bool

Options:

Description:Flag to correct volumetric locking

• boundaryThe list of boundary IDs from the mesh where this boundary condition applies

C++ Type:std::vector

Options:

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

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

C++ Type:std::vector

Options:

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

### 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.

• seed0The seed for the master random number generator

Default:0

C++ Type:unsigned int

Options:

Description:The seed for the master random number generator

• implicitTrueDetermines whether this object is calculated using an implicit or explicit form

Default:True

C++ Type:bool

Options:

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

• constant_onNONEWhen ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

Default:NONE

C++ Type:MooseEnum

Options:NONE ELEMENT SUBDOMAIN

Description:When ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

• output_propertiesList of material properties, from this material, to output (outputs must also be defined to an output type)

C++ Type:std::vector

Options:

Description:List of material properties, from this material, to output (outputs must also be defined to an output type)

• outputsnone Vector of output names were you would like to restrict the output of variables(s) associated with this object

Default:none

C++ Type:std::vector

Options:

Description:Vector of output names were you would like to restrict the output of variables(s) associated with this object