PyC Creep

Computes the irradiation creep for PyC in an implicit manner

Description

The irradiation creep correlation for Pyrolytic Carbon, in PyCCreep, is taken from Petti et al. (2004) and Powers and Wirth (2010). With as the creep constant, as one component of the principal stress, as the Poisson ratio for creep, and as the fast neutron flux, the creep rate is given as (1) The value of is . is (2) where (3) and with , in g/cm and in C. At the expense of inverting a matrix, it is possible to determine the creep strain increment in an implicit fashion, allowing arbitrarily large time steps without unstable creep response.

Example Input Syntax


[./solid1]
type = PyCCreep
block = 1
flux = flux
temperature = temp
[../]
(test/tests/tensor_mechanics/pyc_creep/pyc_creep.i)

Input Parameters

• fluxCoupled flux

C++ Type:std::vector

Description:Coupled flux

• temperatureCoupled temperature

C++ Type:std::vector

Description:Coupled temperature

• densityInitial fuel density

C++ Type:double

Description:Initial fuel density

Required Parameters

• store_stress_oldFalseParameter which indicates whether the old stress state, required for the HHT time integration scheme and Rayleigh damping, needs to be stored

Default:False

C++ Type:bool

Description:Parameter which indicates whether the old stress state, required for the HHT time integration scheme and Rayleigh damping, needs to be stored

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

C++ Type:std::vector

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

• 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

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.

• 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

• 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

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

Optional Parameters

• 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.

• enableTrueSet the enabled status of the MooseObject.

Default:True

C++ Type:bool

Description:Set the enabled status of the MooseObject.

• seed0The seed for the master random number generator

Default:0

C++ Type:unsigned int

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

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

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

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

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

References

1. D. Petti, P. Martin, M. Phelip, and R. Ballinger. Development of improved models and designs for coated-particle gas reactor fuels. Technical Report INL/EXT-05-02615, Idaho National Laboratory, December 2004.[BibTeX]
2. J. J. Powers and B. D. Wirth. A review of TRISO fuel performance models. Journal of Nuclear Materials, 405:74â€“82, 2010.[BibTeX]