# FeCrAl Oxidation and Corrosion AuxKernel

Calculates the oxidation and corrosion of FeCrAl cladding

## Description

The oxidation of FeCrAl cladding, FeCrAlOxideAux is calculated based upon a parabolic rate law to determine the mass gain of oxide. The mass gain is then converted into an oxide thickness. Currently, the oxidation model is not coupled to the Coolant Channel model to affect the heat transfer coefficient as the cladding becomes oxidized. The model presented here was developed for Kanthal APMT, which is one of the candidate ATF FeCrAl cladding alloys. The model was also developed for high temperature steam, resulting in low oxidation rates at normal operating temperatures.

It is expected that oxidation of FeCrAl alloys will be negligible during normal operation and the model can be applied to the normal operating regime. The parabolic rate constant was determined by Pint et al. (2015): (1) where is the parabolic rate constant in units of g/cm-s, is a constant equal to 7.84 g/cm-s, and is an activation energy in units of K with a value of 41373.7.

The mass gain due to the oxide formation is then calculated by (2) where is the mass gain due to oxidation in units of mg/cm. Then the oxide thickness is determined by multiplying the mass gain by the conversion factor of 5.35 m-(cm/mg) as proposed by JÃ¶nsson et al. (2013).

## Example Input Syntax


[AuxKernels]
[./oxide]
type = FeCrAlOxideAux
variable = oxide_thickness
temperature = temp
boundary = 3
execute_on = timestep_end
[../]
[]
(test/tests/fecral/corrosion/corrosion_test_fecral.i)

## Input Parameters

• variableThe name of the variable that this object applies to

C++ Type:AuxVariableName

Description:The name of the variable that this object applies to

• temperaturecladding wall surface temperature (K)

C++ Type:std::vector

Description:cladding wall surface temperature (K)

### Required Parameters

• parabolic_rate_constant784Coefficient in parabolic rate equation (kg^2/m^4-s

Default:784

C++ Type:double

Description:Coefficient in parabolic rate equation (kg^2/m^4-s

• oxide_scale_factor1oxide scale factor

Default:1

C++ Type:double

Description:oxide scale factor

• start_time0When to turn on oxide growth.

Default:0

C++ Type:double

Description:When to turn on oxide growth.

• activation_energy41373.7Activation energy in units of K (Q/R)

Default:41373.7

C++ Type:double

Description:Activation energy in units of K (Q/R)

• end_timeinfWhen to turn off oxide growth.

Default:inf

C++ Type:double

Description:When to turn off oxide growth.

• 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

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.

• 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

• 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

• 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

• 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.

## References

1. Bo JÃ¶nsson, Qin Lu, and Dilip Chandrasekaran. Oxidation and Creep Limited Lifetime of Kanthal APMT, a Dispersion Strengthened FeCrAlMo Alloy Designed for Strength and Oxidation Resistance at High Temperatures. Oxidation of Metals, 79:29â€“39, 2013.[BibTeX]
2. B.A. Pint, K.A. Terrani, Y. Yamamoto, and L.L. Snead. Material Selection for Accident Tolerant Fuel Cladding. Metallurgical and Materials Transactions E, 2E:190â€“196, 2015.[BibTeX]