# Compute Isotropic Elasticity Tensor

Compute a constant isotropic elasticity tensor.

## Description

The material ComputeIsotropicElasticityTensor builds the isotropic elasticity (stiffness) tensor with two user provided elastic constants.

The isotropic elasticity tensor is given, in engineering matrix notation (Malvern, 1969), as (1)

ComputeIsotropicElasticityTensor accepts as an argument two of five isotropic elastic constants: lambda , the shear modulus , the bulk modulus , the Young's modulus , or the Poisson's ratio . The material includes the conversions into Lame constants, see Slaughter (2012) for the conversion equations among the isotropic elastic constants.

## Example Input File Syntax

[./elast_tensor]
type = ComputeIsotropicElasticityTensor
youngs_modulus = 1e6
poissons_ratio = 0.25
[../]

## Input Parameters

• 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.

• elasticity_tensor_prefactorOptional function to use as a scalar prefactor on the elasticity tensor.

C++ Type:FunctionName

Options:

Description:Optional function to use as a scalar prefactor on the elasticity tensor.

• 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

• shear_modulusThe shear modulus of the material.

C++ Type:double

Options:

Description:The shear modulus of the material.

• poissons_ratioPoisson's ratio for the material.

C++ Type:double

Options:

Description:Poisson's ratio for the material.

• bulk_modulusThe bulk modulus for the material.

C++ Type:double

Options:

Description:The bulk modulus for the material.

• 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

• youngs_modulusYoung's modulus of the material.

C++ Type:double

Options:

Description:Young's modulus of the material.

• 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

• lambdaLame's first constant for the material.

C++ Type:double

Options:

Description:Lame's first constant for the material.

### Optional Parameters

• 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.

• 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.

• 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

## References

1. Lawrence E Malvern. Introduction to the Mechanics of a Continuous Medium. Prentice-Hall, 1969.[BibTeX]
2. William S Slaughter. The Linearized Theory of Elasticity. Springer Science & Business Media, 2012.[BibTeX]