# Fission Rate Axial AuxKernel

Calculates the amount of fission rate based on relative axial position from the ends of the fuel stack

## Description

The model in FissionRateAxialAux calculates the fission rate from the user defined fuel stack top and bottom with a normalized sixth order polynomial function. (1) where is the normalized current node location, defined as (2)

## Example Input Syntax

[./fissionrate]
type = FissionRateAxialAux
axis = 1
block = 1
variable = fission_rate
value = 1.183e19 # corrected average power to 200 W/cm
fuel_bottom = -2.5
fuel_top = 2.5
function = axial_power_ramp
[../]
(test/tests/fission_rate_axial/fission_rate_axial_test_coords.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

• valueThe average volumetric fission rate

C++ Type:double

Description:The average volumetric fission rate

• axisThe axis used (0, 1, or 2 for x, y, or z).

C++ Type:int

Description:The axis used (0, 1, or 2 for x, y, or z).

### Required Parameters

• functionThe function that describes the fission rate.

C++ Type:FunctionName

Description:The function that describes the fission rate.

• fuel_top_boundaryThe top boundary of the pellet stack.

C++ Type:unsigned int

Description:The top boundary of the pellet stack.

• fuel_topThe coordinate at the top of the fuel stack

C++ Type:double

Description:The coordinate at the top of the fuel stack

• fuel_bottomThe coordinate at the bottom of the fuel stack

C++ Type:double

Description:The coordinate at the bottom of the fuel stack

• fuel_bottom_boundaryThe bottom boundary of the pellet stack.

C++ Type:unsigned int

Description:The bottom boundary of the pellet stack.

• 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.