- variableThe name of the variable that this boundary condition applies to
C++ Type:std::vector

Description:The name of the variable that this boundary condition applies to

- 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

- diffusivityThe name of the diffusivity material property that will be used in the flux computation.
C++ Type:MaterialPropertyName

Description:The name of the diffusivity material property that will be used in the flux computation.

# SideFluxIntegral

Computes the integral of the flux over the specified boundary

## Example Input Syntax

```
[Postprocessors]
[./average_temperature]
type = ElementAverageValue
variable = temperature
[../]
[./outlet_heat_flux]
type = SideFluxIntegral
variable = temperature
boundary = right
diffusivity = thermal_conductivity
[../]
[]
```

(tutorials/darcy_thermo_mech/step08_postprocessors/problems/step8.i)#### /opt/civet/build_0/moose/tutorials/darcy_thermo_mech/step08_postprocessors/problems/step8.i

```
[Mesh]
type = GeneratedMesh
dim = 2
nx = 200
ny = 10
xmax = 0.304 # Length of test chamber
ymax = 0.0257 # Test chamber radius
[]
[Variables]
[./pressure]
[../]
[./temperature]
initial_condition = 300 # Start at room temperature
[../]
[]
[AuxVariables]
[./velocity_x]
order = CONSTANT
family = MONOMIAL
[../]
[./velocity_y]
order = CONSTANT
family = MONOMIAL
[../]
[./velocity_z]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./darcy_pressure]
type = DarcyPressure
variable = pressure
[../]
[./heat_conduction]
type = HeatConduction
variable = temperature
[../]
[./heat_conduction_time_derivative]
type = HeatCapacityConductionTimeDerivative
variable = temperature
[../]
[./heat_convection]
type = DarcyConvection
variable = temperature
darcy_pressure = pressure
[../]
[]
[AuxKernels]
[./velocity_x]
type = DarcyVelocity
variable = velocity_x
component = x
execute_on = timestep_end
darcy_pressure = pressure
[../]
[./velocity_y]
type = DarcyVelocity
variable = velocity_y
component = y
execute_on = timestep_end
darcy_pressure = pressure
[../]
[./velocity_z]
type = DarcyVelocity
variable = velocity_z
component = z
execute_on = timestep_end
darcy_pressure = pressure
[../]
[]
[BCs]
[./inlet]
type = DirichletBC
variable = pressure
boundary = left
value = 4000 # (Pa) From Figure 2 from paper. First data point for 1mm spheres.
[../]
[./outlet]
type = DirichletBC
variable = pressure
boundary = right
value = 0 # (Pa) Gives the correct pressure drop from Figure 2 for 1mm spheres
[../]
[./inlet_temperature]
type = DirichletBC
variable = temperature
boundary = left
value = 350 # (C)
[../]
[./outlet_temperature]
type = HeatConductionOutflow
variable = temperature
boundary = right
[../]
[]
[Materials]
[./column]
type = PackedColumn
sphere_radius = 1
[../]
[]
[Postprocessors]
[./average_temperature]
type = ElementAverageValue
variable = temperature
[../]
[./outlet_heat_flux]
type = SideFluxIntegral
variable = temperature
boundary = right
diffusivity = thermal_conductivity
[../]
[]
[Problem]
type = FEProblem
coord_type = RZ
rz_coord_axis = X
[]
[Executioner]
type = Transient
num_steps = 400
dt = 0.1
solve_type = PJFNK
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
end_time = 110
[./TimeStepper]
type = SolutionTimeAdaptiveDT
dt = 0.1
[../]
[]
[Outputs]
exodus = true
[]
```

## Input Parameters

- execute_onTIMESTEP_ENDThe 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:TIMESTEP_END

C++ Type:ExecFlagEnum

Options:NONE INITIAL LINEAR NONLINEAR TIMESTEP_END TIMESTEP_BEGIN FINAL CUSTOM

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.

### Optional Parameters

- outputsVector of output names were you would like to restrict the output of variables(s) associated with this object
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

- 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.

- allow_duplicate_execution_on_initialFalseIn the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).
Default:False

C++ Type:bool

Options:

Description:In the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).

- 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.

### Advanced Parameters

## Input Files

- modules/heat_conduction/test/tests/heat_conduction/3d_quadrature_gap_heat_transfer/second.i
- modules/combined/test/tests/gap_heat_transfer_htonly/cyl3D.i
- modules/heat_conduction/test/tests/recover/recover.i
- modules/combined/test/tests/gap_heat_transfer_htonly/planar_yz.i
- modules/heat_conduction/test/tests/heat_conduction/2d_quadrature_gap_heat_transfer/nonmatching.i
- modules/heat_conduction/test/tests/heat_conduction/2d_quadrature_gap_heat_transfer/second_order.i
- modules/functional_expansion_tools/examples/2D_interface_no_material/main.i
- modules/functional_expansion_tools/examples/2D_interface/main.i
- test/tests/misc/line_source/line_source.i
- modules/combined/test/tests/gap_heat_transfer_htonly/planar_xz.i
- modules/combined/test/tests/gap_heat_transfer_htonly/gap_heat_transfer_htonly_test.i
- modules/combined/test/tests/gap_heat_transfer_htonly/cyl2D_yz.i
- tutorials/darcy_thermo_mech/step08_postprocessors/problems/step8.i
- modules/functional_expansion_tools/examples/2D_interface_different_submesh/main.i
- modules/heat_conduction/test/tests/heat_conduction/3d_quadrature_gap_heat_transfer/moving.i
- modules/combined/test/tests/gap_heat_transfer_htonly/gap_heat_transfer_htonly_rspherical.i
- modules/heat_conduction/test/tests/heat_conduction/2d_quadrature_gap_heat_transfer/moving.i
- modules/combined/test/tests/gap_heat_transfer_htonly/sphere3D.i
- modules/combined/test/tests/gap_heat_transfer_htonly/planar_xy.i
- modules/combined/test/tests/gap_heat_transfer_htonly/gap_heat_transfer_htonly_it_plot_test.i
- modules/combined/test/tests/gap_heat_transfer_htonly/cyl2D.i
- modules/combined/test/tests/gap_heat_transfer_htonly/cyl2D_xz.i
- modules/combined/test/tests/gap_heat_transfer_htonly/gap_heat_transfer_htonly_rz_test.i
- test/tests/postprocessors/misc_pps/misc_pps_test.i
- modules/functional_expansion_tools/test/tests/standard_use/interface_coupled.i
- modules/combined/test/tests/gap_heat_transfer_radiation/gap_heat_transfer_radiation_test.i
- modules/heat_conduction/test/tests/heat_conduction/3d_quadrature_gap_heat_transfer/nonmatching.i
- modules/combined/test/tests/gap_heat_transfer_htonly/sphere2DRZ.i

#### modules/heat_conduction/test/tests/heat_conduction/3d_quadrature_gap_heat_transfer/second.i

```
[Mesh]
file = nonmatching.e
second_order = true
[]
[Variables]
[./temp]
order = SECOND
[../]
[]
[Kernels]
[./hc]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./left]
type = DirichletBC
variable = temp
boundary = leftleft
value = 1000
[../]
[./right]
type = DirichletBC
variable = temp
boundary = rightright
value = 400
[../]
[]
[ThermalContact]
[./left_to_right]
slave = leftright
quadrature = true
master = rightleft
variable = temp
type = GapHeatTransfer
order = SECOND
[../]
[]
[Materials]
[./hcm]
type = HeatConductionMaterial
block = 'left right'
specific_heat = 1
thermal_conductivity = 1
[../]
[]
[Postprocessors]
[./left]
type = SideFluxIntegral
variable = temp
boundary = leftright
diffusivity = thermal_conductivity
[../]
[./right]
type = SideFluxIntegral
variable = temp
boundary = rightleft
diffusivity = thermal_conductivity
[../]
[]
[Executioner]
type = Steady
#Preconditioned JFNK (default)
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
[]
[Outputs]
exodus = true
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/cyl3D.i

```
#
# 3D Cylindrical Gap Heat Transfer Test.
#
# This test exercises 3D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of an inner solid cylinder of radius = 1 unit, and outer
# hollow cylinder with an inner radius of 2. In other words, the gap between
# them is 1 radial unit in length.
#
# The conductivity of both cylinders is set very large to achieve a uniform
# temperature in each cylinder. The temperature of the center node of the
# inner cylinder is ramped from 100 to 200 over one time unit. The temperature
# of the outside of the outer, hollow cylinder is held fixed at 100.
#
# A simple analytical solution is possible for the integrated heat flux
# between the inner and outer cylinders:
#
# Integrated Flux = (T_left - T_right) * (gapK/(r*ln(r2/r1))) * Area
#
# For gapK = 1 (default value)
#
# The area is taken as the area of the slave (inner) surface:
#
# Area = 2 * pi * h * r, where h is the height of the cylinder.
#
# The integrated heat flux across the gap at time 1 is then:
#
# 2*pi*h*k*delta_T/(ln(r2/r1))
# 2*pi*1*1*100/(ln(2/1)) = 906.5 watts
#
# For comparison, see results from the integrated flux post processors.
# This simulation makes use of symmetry, so only 1/4 of the cylinders is meshed
# As such, the integrated flux from the post processors is 1/4 of the total,
# or 226.6 watts.
# The value coming from the post processor is slightly less than this
# but converges as mesh refinement increases.
#
# Simulating contact is challenging. Regression tests that exercise
# contact features can be difficult to solve consistently across multiple
# platforms. While designing these tests, we felt it worth while to note
# some aspects of these tests. The following applies to:
# sphere3D.i, sphere2DRZ.i, cyl2D.i, and cyl3D.i.
# 1. We decided that to perform consistently across multiple platforms we
# would use very small convergence tolerance. In this test we chose an
# nl_rel_tol of 1e-12.
# 2. Due to such a high value for thermal conductivity (used here so that the
# domains come to a uniform temperature) the integrated flux at time = 0
# was relatively large (the value coming from SideIntegralFlux =
# -_diffusion_coef[_qp]*_grad_u[_qp]*_normals[_qp] where the diffusion coefficient
# here is thermal conductivity).
# Even though _grad_u[_qp] is small, in this case the diffusion coefficient
# is large. The result is a number that isn't exactly zero and tends to
# fail exodiff. For this reason the parameter execute_on = initial should not
# be used. That parameter is left to default settings in these regression tests.
#
[GlobalParams]
order = SECOND
family = LAGRANGE
[]
[Mesh]
file = cyl3D.e
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1'
y = '100 200'
[../]
[]
[Variables]
[./temp]
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_conductance]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat_conduction]
type = HeatConduction
variable = temp
[../]
[]
[AuxKernels]
[./gap_cond]
type = MaterialRealAux
property = gap_conductance
variable = gap_conductance
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 1000000.0
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
gap_conductivity = 1
quadrature = true
gap_geometry_type = CYLINDER
cylinder_axis_point_1 = '0 0 0'
cylinder_axis_point_2 = '0 1 0'
[../]
[]
[BCs]
[./mid]
type = FunctionPresetBC
boundary = 5
variable = temp
function = temp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[Executioner]
type = Transient
#Preconditioned JFNK (default)
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_factor_mat_solver_package'
petsc_options_value = 'lu superlu_dist'
dt = 1
dtmin = 0.01
end_time = 1
nl_rel_tol = 1e-12
nl_abs_tol = 1e-7
[./Quadrature]
order = fifth
side_order = seventh
[../]
[]
[Outputs]
exodus = true
[./Console]
type = Console
[../]
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
```

#### modules/heat_conduction/test/tests/recover/recover.i

```
[GlobalParams]
order = SECOND
family = LAGRANGE
[]
[Problem]
coord_type = RZ
[]
[Mesh]
file = recover_in.e
[]
[Variables]
[./temp]
initial_condition = 580.0
[../]
[]
[AuxVariables]
[./gap_cond]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat]
type = HeatConduction
variable = temp
[../]
[./heat_source]
type = BodyForce
variable = temp
block = pellet_type_1
value = 1e-2
function = 't'
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 5
slave = 10
quadrature = true
[../]
[]
[BCs]
[./outside]
type = DirichletBC
value = 580
boundary = '1 2 3'
variable = temp
[../]
[./edge]
type = PresetBC
value = 700
boundary = 10
variable = temp
[../]
[]
[Materials]
[./thermal_3]
type = HeatConductionMaterial
block = 3
thermal_conductivity = 5
specific_heat = 12
[../]
[./thermal_1]
type = HeatConductionMaterial
block = 1
thermal_conductivity = 16.0
specific_heat = 330.0
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options = '-snes_ksp_ew'
petsc_options_iname = '-pc_type -pc_factor_mat_solver_package'
petsc_options_value = ' lu superlu_dist'
nl_rel_tol = 1e-9
nl_abs_tol = 1e-11
start_time = -200
n_startup_steps = 1
end_time = 1.02e5
num_steps = 10
dtmax = 2e6
dtmin = 1
[./TimeStepper]
type = IterationAdaptiveDT
dt = 2.0e2
optimal_iterations = 15
iteration_window = 2
[../]
[./Quadrature]
order = FIFTH
side_order = SEVENTH
[../]
[]
[Postprocessors]
[./ave_temp_interior]
type = SideAverageValue
boundary = 9
variable = temp
execute_on = 'initial linear'
[../]
[./avg_clad_temp]
type = SideAverageValue
boundary = 7
variable = temp
execute_on = 'initial timestep_end'
[../]
[./flux_from_clad]
type = SideFluxIntegral
variable = temp
boundary = 5
diffusivity = thermal_conductivity
execute_on = timestep_end
[../]
[./_dt]
type = TimestepSize
execute_on = timestep_end
[../]
[]
[Outputs]
exodus = true
[./console]
type = Console
max_rows = 25
[../]
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/planar_yz.i

```
# 1-D Gap Heat Transfer Test without mechanics
#
# This test exercises 1-D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of two element blocks in the y-z plane. Each element block
# is a square. They sit next to one another with a unit between them.
#
# The conductivity of both blocks is set very large to achieve a uniform temperature
# across each block. The temperature of the far bottom boundary
# is ramped from 100 to 200 over one time unit. The temperature of the far top
# boundary is held fixed at 100.
#
# A simple analytical solution is possible for the heat flux between the blocks:
#
# Flux = (T_left - T_right) * (gapK/gap_width)
#
# The gap conductivity is specified as 1, thus
#
# gapK(Tavg) = 1.0*Tavg
#
# The heat flux across the gap at time = 1 is then:
#
# Flux = 100 * (1.0/1.0) = 100
#
# For comparison, see results from the flux post processors. These results
# are the same as for the unit 1-D gap heat transfer between two unit cubes.
[Mesh]
file = simple_2D.e
[]
[MeshModifiers]
[./rotate]
type = Transform
transform = ROTATE
vector_value = '0 90 90'
[../]
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1 2'
y = '100 200 200'
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
[../]
[]
[Variables]
[./temp]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_cond]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./temp_far_bottom]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_top]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[AuxKernels]
[./conductance]
type = MaterialRealAux
property = gap_conductance
variable = gap_cond
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 100000000.0
[../]
[./density]
type = Density
block = '1 2'
density = 1.0
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-ksp_gmres_restart -pc_type -pc_hypre_type -pc_hypre_boomeramg_max_iter'
petsc_options_value = '201 hypre boomeramg 4'
line_search = 'none'
nl_rel_tol = 1e-12
l_tol = 1e-3
l_max_its = 100
dt = 1e-1
end_time = 1.0
[]
[Postprocessors]
[./temp_bottom]
type = SideAverageValue
boundary = 2
variable = temp
execute_on = 'initial timestep_end'
[../]
[./temp_top]
type = SideAverageValue
boundary = 3
variable = temp
execute_on = 'initial timestep_end'
[../]
[./flux_bottom]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[./flux_top]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[]
[Outputs]
exodus = true
[]
```

#### modules/heat_conduction/test/tests/heat_conduction/2d_quadrature_gap_heat_transfer/nonmatching.i

```
[Mesh]
file = nonmatching.e
[]
[Variables]
[./temp]
[../]
[]
[Kernels]
[./hc]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./left]
type = DirichletBC
variable = temp
boundary = leftleft
value = 1000
[../]
[./right]
type = DirichletBC
variable = temp
boundary = rightright
value = 400
[../]
[]
[ThermalContact]
[./left_to_right]
slave = leftright
quadrature = true
master = rightleft
variable = temp
type = GapHeatTransfer
[../]
[]
[Materials]
[./hcm]
type = HeatConductionMaterial
block = 'left right'
specific_heat = 1
thermal_conductivity = 1
[../]
[./gap_conductance]
type = GenericConstantMaterial
prop_names = 'gap_conductance gap_conductance_dT'
boundary = 'leftright rightleft'
prop_values = '1 0'
[../]
[]
[Postprocessors]
[./left]
type = SideFluxIntegral
variable = temp
boundary = leftright
diffusivity = thermal_conductivity
[../]
[./right]
type = SideFluxIntegral
variable = temp
boundary = rightleft
diffusivity = thermal_conductivity
[../]
[]
[Executioner]
type = Steady
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
[]
[Outputs]
exodus = true
[]
```

#### modules/heat_conduction/test/tests/heat_conduction/2d_quadrature_gap_heat_transfer/second_order.i

```
[Mesh]
file = nonmatching.e
second_order = true
[]
[Variables]
[./temp]
order = SECOND
[../]
[]
[Kernels]
[./hc]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./left]
type = DirichletBC
variable = temp
boundary = leftleft
value = 1000
[../]
[./right]
type = DirichletBC
variable = temp
boundary = rightright
value = 400
[../]
[]
[ThermalContact]
[./left_to_right]
slave = leftright
quadrature = true
master = rightleft
variable = temp
type = GapHeatTransfer
order = SECOND
[../]
[]
[Materials]
[./hcm]
type = HeatConductionMaterial
block = 'left right'
specific_heat = 1
thermal_conductivity = 1
[../]
[]
[Postprocessors]
[./left]
type = SideFluxIntegral
variable = temp
boundary = leftright
diffusivity = thermal_conductivity
[../]
[./right]
type = SideFluxIntegral
variable = temp
boundary = rightleft
diffusivity = thermal_conductivity
[../]
[]
[Executioner]
type = Steady
#Preconditioned JFNK (default)
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
[]
[Outputs]
exodus = true
[]
```

#### modules/functional_expansion_tools/examples/2D_interface_no_material/main.i

```
# Derived from the example '2D_interface' with the following differences:
#
# 1) No materials are used
[Mesh]
type = GeneratedMesh
dim = 2
xmin = 0.0
xmax = 0.4
nx = 6
ymin = 0.0
ymax = 10.0
ny = 20
[]
[Variables]
[./m]
[../]
[]
[Kernels]
[./diff_m]
type = Diffusion
variable = m
[../]
[./time_diff_m]
type = TimeDerivative
variable = m
[../]
[./source_m]
type = BodyForce
variable = m
value = 100
[../]
[]
[ICs]
[./start_m]
type = ConstantIC
value = 2
variable = m
[../]
[]
[BCs]
[./interface_value]
type = FXValueBC
variable = m
boundary = right
function = FX_Basis_Value_Main
[../]
[./interface_flux]
type = FXFluxBC
boundary = right
variable = m
function = FX_Basis_Flux_Main
[../]
[]
[Functions]
[./FX_Basis_Value_Main]
type = FunctionSeries
series_type = Cartesian
orders = '4'
physical_bounds = '0.0 10'
y = Legendre
[../]
[./FX_Basis_Flux_Main]
type = FunctionSeries
series_type = Cartesian
orders = '5'
physical_bounds = '0.0 10'
y = Legendre
[../]
[]
[UserObjects]
[./FX_Flux_UserObject_Main]
type = FXBoundaryFluxUserObject
function = FX_Basis_Flux_Main
variable = m
boundary = right
diffusivity = 0.1
[../]
[]
[Postprocessors]
[./average_interface_value]
type = SideAverageValue
variable = m
boundary = right
[../]
[./total_flux]
type = SideFluxIntegral
variable = m
boundary = right
diffusivity = 0.1
[../]
[./picard_iterations]
type = NumPicardIterations
execute_on = 'initial timestep_end'
[../]
[]
[Executioner]
type = Transient
num_steps = 10
dt = 1.0
solve_type = PJFNK
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
picard_max_its = 30
nl_rel_tol = 1e-8
nl_abs_tol = 1e-9
picard_rel_tol = 1e-8
picard_abs_tol = 1e-9
[]
[Outputs]
exodus = true
[]
[MultiApps]
[./FXTransferApp]
type = TransientMultiApp
input_files = sub.i
sub_cycling = true
[../]
[]
[Transfers]
[./FluxToSub]
type = MultiAppFXTransfer
direction = to_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Flux_UserObject_Main
multi_app_object_name = FX_Basis_Flux_Sub
[../]
[./ValueToMe]
type = MultiAppFXTransfer
direction = from_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Basis_Value_Main
multi_app_object_name = FX_Value_UserObject_Sub
[../]
[./FluxToMe]
type = MultiAppFXTransfer
direction = from_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Basis_Flux_Main
multi_app_object_name = FX_Flux_UserObject_Sub
[../]
[]
```

#### modules/functional_expansion_tools/examples/2D_interface/main.i

```
# Basic example coupling a master and sub app at an interface in a 2D model.
# The master app provides a flux term to the sub app via Functional Expansions, which then performs
# its calculations. The sub app's interface conditions, both value and flux, are transferred back
# to the master app
[Mesh]
type = GeneratedMesh
dim = 2
xmin = 0.0
xmax = 0.4
nx = 6
ymin = 0.0
ymax = 10.0
ny = 20
[]
[Variables]
[./m]
[../]
[]
[Kernels]
[./diff_m]
type = HeatConduction
variable = m
[../]
[./time_diff_m]
type = HeatConductionTimeDerivative
variable = m
[../]
[./source_m]
type = BodyForce
variable = m
value = 100
[../]
[]
[Materials]
[./Impervium]
type = GenericConstantMaterial
prop_names = 'thermal_conductivity specific_heat density'
prop_values = '0.00001 50.0 100.0' # W/(cm K), J/(g K), g/cm^3
[../]
[]
[ICs]
[./start_m]
type = ConstantIC
value = 2
variable = m
[../]
[]
[BCs]
[./interface_value]
type = FXValueBC
variable = m
boundary = right
function = FX_Basis_Value_Main
[../]
[./interface_flux]
type = FXFluxBC
boundary = right
variable = m
function = FX_Basis_Flux_Main
[../]
[]
[Functions]
[./FX_Basis_Value_Main]
type = FunctionSeries
series_type = Cartesian
orders = '4'
physical_bounds = '0.0 10'
y = Legendre
[../]
[./FX_Basis_Flux_Main]
type = FunctionSeries
series_type = Cartesian
orders = '5'
physical_bounds = '0.0 10'
y = Legendre
[../]
[]
[UserObjects]
[./FX_Flux_UserObject_Main]
type = FXBoundaryFluxUserObject
function = FX_Basis_Flux_Main
variable = m
boundary = right
diffusivity = thermal_conductivity
[../]
[]
[Postprocessors]
[./average_interface_value]
type = SideAverageValue
variable = m
boundary = right
[../]
[./total_flux]
type = SideFluxIntegral
variable = m
boundary = right
diffusivity = thermal_conductivity
[../]
[./picard_iterations]
type = NumPicardIterations
execute_on = 'initial timestep_end'
[../]
[]
[Executioner]
type = Transient
num_steps = 10
dt = 1.0
solve_type = PJFNK
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
picard_max_its = 30
nl_rel_tol = 1e-8
nl_abs_tol = 1e-9
picard_rel_tol = 1e-8
picard_abs_tol = 1e-9
[]
[Outputs]
exodus = true
[]
[MultiApps]
[./FXTransferApp]
type = TransientMultiApp
input_files = sub.i
sub_cycling = true
[../]
[]
[Transfers]
[./FluxToSub]
type = MultiAppFXTransfer
direction = to_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Flux_UserObject_Main
multi_app_object_name = FX_Basis_Flux_Sub
[../]
[./ValueToMe]
type = MultiAppFXTransfer
direction = from_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Basis_Value_Main
multi_app_object_name = FX_Value_UserObject_Sub
[../]
[./FluxToMe]
type = MultiAppFXTransfer
direction = from_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Basis_Flux_Main
multi_app_object_name = FX_Flux_UserObject_Sub
[../]
[]
```

#### test/tests/misc/line_source/line_source.i

```
[Mesh]
type = FileMesh
file = line_source_cube.e
dim = 2
[]
[Variables]
[./u]
[../]
[]
[Kernels]
[./diff]
type = Diffusion
variable = u
block = bulk
[../]
[./heating]
type = BodyForce
variable = u
function = 1
block = heater
[../]
[]
[BCs]
[./outside]
type = DirichletBC
variable = u
boundary = outside
value = 0
[../]
[]
[Materials]
[./diffusivity]
type = GenericConstantMaterial
block = 'bulk heater'
prop_names = diffusivity
prop_values = 1
[../]
[]
[Postprocessors]
[./total_flux]
type = SideFluxIntegral
variable = u
boundary = outside
diffusivity = diffusivity
[../]
[]
[Executioner]
type = Steady
solve_type = PJFNK
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
[]
[Outputs]
exodus = true
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/planar_xz.i

```
# 1-D Gap Heat Transfer Test without mechanics
#
# This test exercises 1-D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of two element blocks in the x-z plane. Each element block
# is a square. They sit next to one another with a unit between them.
#
# The conductivity of both blocks is set very large to achieve a uniform temperature
# across each block. The temperature of the far bottom boundary
# is ramped from 100 to 200 over one time unit. The temperature of the far top
# boundary is held fixed at 100.
#
# A simple analytical solution is possible for the heat flux between the blocks:
#
# Flux = (T_left - T_right) * (gapK/gap_width)
#
# The gap conductivity is specified as 1, thus
#
# gapK(Tavg) = 1.0*Tavg
#
# The heat flux across the gap at time = 1 is then:
#
# Flux = 100 * (1.0/1.0) = 100
#
# For comparison, see results from the flux post processors. These results
# are the same as for the unit 1-D gap heat transfer between two unit cubes.
[Mesh]
file = simple_2D.e
[]
[MeshModifiers]
[./rotate]
type = Transform
transform = ROTATE
vector_value = '0 90 0'
[../]
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1 2'
y = '100 200 200'
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
[../]
[]
[Variables]
[./temp]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_cond]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./temp_far_bottom]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_top]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[AuxKernels]
[./conductance]
type = MaterialRealAux
property = gap_conductance
variable = gap_cond
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 100000000.0
[../]
[./density]
type = Density
block = '1 2'
density = 1.0
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-ksp_gmres_restart -pc_type -pc_hypre_type -pc_hypre_boomeramg_max_iter'
petsc_options_value = '201 hypre boomeramg 4'
line_search = 'none'
nl_rel_tol = 1e-12
l_tol = 1e-3
l_max_its = 100
dt = 1e-1
end_time = 1.0
[]
[Postprocessors]
[./temp_bottom]
type = SideAverageValue
boundary = 2
variable = temp
execute_on = 'initial timestep_end'
[../]
[./temp_top]
type = SideAverageValue
boundary = 3
variable = temp
execute_on = 'initial timestep_end'
[../]
[./flux_bottom]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[./flux_top]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[]
[Outputs]
exodus = true
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/gap_heat_transfer_htonly_test.i

```
#
# 1-D Gap Heat Transfer Test without mechanics
#
# This test exercises 1-D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of two element blocks containing one element each. Each
# element is a unit cube. They sit next to one another with a unit between them.
#
# The conductivity of both blocks is set very large to achieve a uniform temperature
# across each block. The temperature of the far left boundary
# is ramped from 100 to 200 over one time unit. The temperature of the far right
# boundary is held fixed at 100.
#
# A simple analytical solution is possible for the heat flux between the blocks:
#
# Flux = (T_left - T_right) * (gapK/gap_width)
#
# The gap conductivity is specified as 1, thus
#
# gapK(Tavg) = 1.0*Tavg
#
#
# The heat flux across the gap at time = 1 is then:
#
# Flux(2) = 100 * (1.0/1.0) = 100
#
# For comparison, see results from the flux post processors
#
# This test has been augmented with a second scalar field that solves nearly
# the same problem. The conductivity has been changed to 10. Thus, the
# flux for the second field is 1000.
#
[Mesh]
file = gap_heat_transfer_htonly_test.e
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1 2'
y = '100 200 200'
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
[../]
[./awesomium_contact]
type = GapHeatTransfer
variable = awesomium
master = 3
slave = 2
gap_conductivity = 10
appended_property_name = _awesomium
[../]
[]
[Variables]
[./temp]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[./awesomium]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_cond]
order = CONSTANT
family = MONOMIAL
[../]
[./gap_cond_awesomium]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat]
type = HeatConduction
variable = temp
[../]
[./awe]
type = HeatConduction
variable = awesomium
[../]
[]
[BCs]
[./temp_far_left]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[./awesomium_far_left]
type = FunctionPresetBC
boundary = 1
variable = awesomium
function = temp
[../]
[./awesomium_far_right]
type = PresetBC
boundary = 4
variable = awesomium
value = 100
[../]
[]
[AuxKernels]
[./conductance]
type = MaterialRealAux
property = gap_conductance
variable = gap_cond
boundary = 2
[../]
[./conductance_awe]
type = MaterialRealAux
property = gap_conductance_awesomium
variable = gap_cond_awesomium
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 100000000.0
[../]
[./density]
type = Density
block = '1 2'
density = 1.0
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-ksp_gmres_restart -pc_type -pc_hypre_type -pc_hypre_boomeramg_max_iter'
petsc_options_value = '201 hypre boomeramg 4'
line_search = 'none'
nl_rel_tol = 1e-12
l_tol = 1e-3
l_max_its = 100
dt = 1e-1
end_time = 1.0
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
execute_on = 'initial timestep_end'
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
execute_on = 'initial timestep_end'
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[./awe_left]
type = SideAverageValue
boundary = 2
variable = awesomium
execute_on = 'initial timestep_end'
[../]
[./awe_right]
type = SideAverageValue
boundary = 3
variable = awesomium
execute_on = 'initial timestep_end'
[../]
[./awe_flux_left]
type = SideFluxIntegral
variable = awesomium
boundary = 2
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[./awe_flux_right]
type = SideFluxIntegral
variable = awesomium
boundary = 3
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[]
[Outputs]
exodus = true
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/cyl2D_yz.i

```
#
# 2D Cylindrical Gap Heat Transfer Test.
#
# This test exercises 2D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of an inner solid cylinder of radius = 1 unit, and outer
# hollow cylinder with an inner radius of 2 in the y-z plane. In other words,
# the gap between them is 1 radial unit in length.
#
# The calculated results are the same as for the cyl2D.i case in the x-y plane.
[GlobalParams]
order = SECOND
family = LAGRANGE
[]
[Mesh]
file = cyl2D.e
[]
[MeshModifiers]
[./rotate]
type = Transform
transform = ROTATE
vector_value = '0 90 90'
[../]
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1'
y = '100 200'
[../]
[]
[Variables]
[./temp]
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_conductance]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat_conduction]
type = HeatConduction
variable = temp
[../]
[]
[AuxKernels]
[./gap_cond]
type = MaterialRealAux
property = gap_conductance
variable = gap_conductance
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 1000000.0
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
gap_conductivity = 1
quadrature = true
gap_geometry_type = CYLINDER
cylinder_axis_point_1 = '0 0 0'
cylinder_axis_point_2 = '1 0 0'
[../]
[]
[BCs]
[./mid]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_factor_mat_solver_package'
petsc_options_value = 'lu superlu_dist'
dt = 1
dtmin = 0.01
end_time = 1
nl_rel_tol = 1e-12
nl_abs_tol = 1e-7
[./Quadrature]
order = fifth
side_order = seventh
[../]
[]
[Outputs]
exodus = true
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
```

#### tutorials/darcy_thermo_mech/step08_postprocessors/problems/step8.i

```
[Mesh]
type = GeneratedMesh
dim = 2
nx = 200
ny = 10
xmax = 0.304 # Length of test chamber
ymax = 0.0257 # Test chamber radius
[]
[Variables]
[./pressure]
[../]
[./temperature]
initial_condition = 300 # Start at room temperature
[../]
[]
[AuxVariables]
[./velocity_x]
order = CONSTANT
family = MONOMIAL
[../]
[./velocity_y]
order = CONSTANT
family = MONOMIAL
[../]
[./velocity_z]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./darcy_pressure]
type = DarcyPressure
variable = pressure
[../]
[./heat_conduction]
type = HeatConduction
variable = temperature
[../]
[./heat_conduction_time_derivative]
type = HeatCapacityConductionTimeDerivative
variable = temperature
[../]
[./heat_convection]
type = DarcyConvection
variable = temperature
darcy_pressure = pressure
[../]
[]
[AuxKernels]
[./velocity_x]
type = DarcyVelocity
variable = velocity_x
component = x
execute_on = timestep_end
darcy_pressure = pressure
[../]
[./velocity_y]
type = DarcyVelocity
variable = velocity_y
component = y
execute_on = timestep_end
darcy_pressure = pressure
[../]
[./velocity_z]
type = DarcyVelocity
variable = velocity_z
component = z
execute_on = timestep_end
darcy_pressure = pressure
[../]
[]
[BCs]
[./inlet]
type = DirichletBC
variable = pressure
boundary = left
value = 4000 # (Pa) From Figure 2 from paper. First data point for 1mm spheres.
[../]
[./outlet]
type = DirichletBC
variable = pressure
boundary = right
value = 0 # (Pa) Gives the correct pressure drop from Figure 2 for 1mm spheres
[../]
[./inlet_temperature]
type = DirichletBC
variable = temperature
boundary = left
value = 350 # (C)
[../]
[./outlet_temperature]
type = HeatConductionOutflow
variable = temperature
boundary = right
[../]
[]
[Materials]
[./column]
type = PackedColumn
sphere_radius = 1
[../]
[]
[Postprocessors]
[./average_temperature]
type = ElementAverageValue
variable = temperature
[../]
[./outlet_heat_flux]
type = SideFluxIntegral
variable = temperature
boundary = right
diffusivity = thermal_conductivity
[../]
[]
[Problem]
type = FEProblem
coord_type = RZ
rz_coord_axis = X
[]
[Executioner]
type = Transient
num_steps = 400
dt = 0.1
solve_type = PJFNK
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
end_time = 110
[./TimeStepper]
type = SolutionTimeAdaptiveDT
dt = 0.1
[../]
[]
[Outputs]
exodus = true
[]
```

#### modules/functional_expansion_tools/examples/2D_interface_different_submesh/main.i

```
# Derived from the example '2D_interface' with the following differences:
#
# 1) The number of y divisions in the sub app is not the same as the master app
# 2) The subapp mesh is skewed in y
# 3) The Functional Expansion order for the flux term was increased to 7
[Mesh]
type = GeneratedMesh
dim = 2
xmin = 0.0
xmax = 0.4
nx = 6
ymin = 0.0
ymax = 10.0
ny = 20
[]
[Variables]
[./m]
[../]
[]
[Kernels]
[./diff_m]
type = HeatConduction
variable = m
[../]
[./time_diff_m]
type = HeatConductionTimeDerivative
variable = m
[../]
[./source_m]
type = BodyForce
variable = m
value = 100
[../]
[]
[Materials]
[./Impervium]
type = GenericConstantMaterial
prop_names = 'thermal_conductivity specific_heat density'
prop_values = '0.00001 50.0 100.0' # W/(cm K), J/(g K), g/cm^3
[../]
[]
[ICs]
[./start_m]
type = ConstantIC
value = 2
variable = m
[../]
[]
[BCs]
[./interface_value]
type = FXValueBC
variable = m
boundary = right
function = FX_Basis_Value_Main
[../]
[./interface_flux]
type = FXFluxBC
boundary = right
variable = m
function = FX_Basis_Flux_Main
[../]
[]
[Functions]
[./FX_Basis_Value_Main]
type = FunctionSeries
series_type = Cartesian
orders = '4'
physical_bounds = '0.0 10'
y = Legendre
[../]
[./FX_Basis_Flux_Main]
type = FunctionSeries
series_type = Cartesian
orders = '7'
physical_bounds = '0.0 10'
y = Legendre
[../]
[]
[UserObjects]
[./FX_Flux_UserObject_Main]
type = FXBoundaryFluxUserObject
function = FX_Basis_Flux_Main
variable = m
boundary = right
diffusivity = thermal_conductivity
[../]
[]
[Postprocessors]
[./average_interface_value]
type = SideAverageValue
variable = m
boundary = right
[../]
[./total_flux]
type = SideFluxIntegral
variable = m
boundary = right
diffusivity = thermal_conductivity
[../]
[./picard_iterations]
type = NumPicardIterations
execute_on = 'initial timestep_end'
[../]
[]
[Executioner]
type = Transient
num_steps = 10
dt = 1.0
solve_type = PJFNK
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
picard_max_its = 30
nl_rel_tol = 1e-8
nl_abs_tol = 1e-9
picard_rel_tol = 1e-8
picard_abs_tol = 1e-9
[]
[Outputs]
exodus = true
[]
[MultiApps]
[./FXTransferApp]
type = TransientMultiApp
input_files = sub.i
sub_cycling = true
[../]
[]
[Transfers]
[./FluxToSub]
type = MultiAppFXTransfer
direction = to_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Flux_UserObject_Main
multi_app_object_name = FX_Basis_Flux_Sub
[../]
[./ValueToMe]
type = MultiAppFXTransfer
direction = from_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Basis_Value_Main
multi_app_object_name = FX_Value_UserObject_Sub
[../]
[./FluxToMe]
type = MultiAppFXTransfer
direction = from_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Basis_Flux_Main
multi_app_object_name = FX_Flux_UserObject_Sub
[../]
[]
```

#### modules/heat_conduction/test/tests/heat_conduction/3d_quadrature_gap_heat_transfer/moving.i

```
[Mesh]
file = nonmatching.e
displacements = 'disp_x disp_y disp_z'
[]
[Variables]
[./temp]
[../]
[]
[AuxVariables]
[./disp_x]
[../]
[./disp_y]
[../]
[./disp_z]
[../]
[]
[Functions]
[./disp_y]
type = ParsedFunction
value = 0.1*t
[../]
[./left_temp]
type = ParsedFunction
value = 1000+t
[../]
[]
[Kernels]
[./hc]
type = HeatConduction
variable = temp
[../]
[]
[AuxKernels]
[./disp_y]
type = FunctionAux
variable = disp_y
function = disp_y
block = left
[../]
[]
[BCs]
[./left]
type = FunctionDirichletBC
variable = temp
boundary = leftleft
function = left_temp
[../]
[./right]
type = DirichletBC
variable = temp
boundary = rightright
value = 400
[../]
[]
[ThermalContact]
[./left_to_right]
type = GapHeatTransfer
variable = temp
master = rightleft
slave = leftright
quadrature = true
[../]
[]
[Materials]
[./hcm]
type = HeatConductionMaterial
block = 'left right'
specific_heat = 1
thermal_conductivity = 1
use_displaced_mesh = true
[../]
[]
[Postprocessors]
[./left]
type = SideFluxIntegral
variable = temp
boundary = leftright
diffusivity = thermal_conductivity
[../]
[./right]
type = SideFluxIntegral
variable = temp
boundary = rightleft
diffusivity = thermal_conductivity
[../]
[]
[Executioner]
type = Transient
num_steps = 9
dt = 1
#Preconditioned JFNK (default)
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
[]
[Outputs]
exodus = true
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/gap_heat_transfer_htonly_rspherical.i

```
#
# 1-D spherical Gap Heat Transfer Test
#
# This test exercises 1-D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of two "blocks" with a mesh biased toward the gap
# between them. Each block is unit length. The gap between them is one
# unit in length.
#
# The conductivity of both blocks is set very large to achieve a uniform temperature
# across each block. The temperature of the far left boundary
# is ramped from 100 to 200 over one time unit, and then held fixed for an additional
# time unit. The temperature of the far right boundary is held fixed at 100.
#
# A simple analytical solution is possible for the heat flux between the blocks, or spheres in the case of RSPHERICAL.:
#
# Flux = (T_left - T_right) * (gapK/(r^2*((1/r1)-(1/r2))))
#
# For gapK = 1 (default value)
#
# The area is taken as the area of the slave (inner) surface:
#
# Area = 4 * pi * 1 * 1
#
# The integrated heat flux across the gap at time 2 is then:
#
# 4*pi*k*delta_T/((1/r1)-(1/r2))
# 4*pi*1*100/((1/1) - (1/2)) = 2513.3 watts
#
# For comparison, see results from the flux post processors.
#
#
[Problem]
coord_type = RSPHERICAL
[]
[Mesh]
file = gap_heat_transfer_htonly_rspherical.e
construct_side_list_from_node_list = true
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1 2'
y = '100 200 200'
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
[../]
[]
[Variables]
[./temp]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_cond]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./temp_far_left]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[AuxKernels]
[./conductance]
type = MaterialRealAux
property = gap_conductance
variable = gap_cond
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 1e6
[../]
[./density]
type = Density
block = '1 2'
density = 1.0
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
# I don't know enough about this test to say why it needs such a
# loose nl_abs_tol... after timestep 10 the residual basically can't
# be reduced much beyond the initial residual. The test probably
# needs to be revisited to determine why.
nl_abs_tol = 1e-3
nl_rel_tol = 1e-10
l_tol = 1e-6
l_max_its = 100
line_search = 'none'
nl_max_its = 10
dt = 1e-1
dtmin = 1e-1
end_time = 2.0
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
execute_on = 'initial timestep_end'
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
execute_on = 'initial timestep_end'
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
[Outputs]
exodus = true
[]
```

#### modules/heat_conduction/test/tests/heat_conduction/2d_quadrature_gap_heat_transfer/moving.i

```
[Mesh]
file = nonmatching.e
displacements = 'disp_x disp_y'
[]
[Variables]
[./temp]
[../]
[]
[AuxVariables]
[./disp_x]
[../]
[./disp_y]
[../]
[]
[Functions]
[./disp_y]
type = ParsedFunction
value = 0.1*t
[../]
[./left_temp]
type = ParsedFunction
value = 1000+t
[../]
[]
[Kernels]
[./hc]
type = HeatConduction
variable = temp
[../]
[]
[AuxKernels]
[./disp_y]
type = FunctionAux
variable = disp_y
function = disp_y
block = left
[../]
[]
[BCs]
[./left]
type = FunctionDirichletBC
variable = temp
boundary = leftleft
function = left_temp
[../]
[./right]
type = DirichletBC
variable = temp
boundary = rightright
value = 400
[../]
[]
[ThermalContact]
[./left_to_right]
slave = leftright
quadrature = true
master = rightleft
variable = temp
type = GapHeatTransfer
[../]
[]
[Materials]
[./hcm]
type = HeatConductionMaterial
block = 'left right'
specific_heat = 1
thermal_conductivity = 1
use_displaced_mesh = true
[../]
[]
[Postprocessors]
[./left]
type = SideFluxIntegral
variable = temp
boundary = leftright
diffusivity = thermal_conductivity
[../]
[./right]
type = SideFluxIntegral
variable = temp
boundary = rightleft
diffusivity = thermal_conductivity
[../]
[]
[Executioner]
type = Transient
num_steps = 9
dt = 1
#Preconditioned JFNK (default)
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
[]
[Outputs]
exodus = true
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/sphere3D.i

```
#
# 3D Spherical Gap Heat Transfer Test.
#
# This test exercises 3D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of an inner solid sphere of radius = 1 unit, and outer
# hollow sphere with an inner radius of 2. In other words, the gap between
# them is 1 radial unit in length.
#
# The conductivity of both spheres is set very large to achieve a uniform
# temperature in each sphere. The temperature of the center node of the
# inner sphere is ramped from 100 to 200 over one time unit. The
# temperature of the outside of the outer, hollow sphere is held fixed
# at 100.
#
# A simple analytical solution is possible for the integrated heat flux
# between the inner and outer spheres:
#
# Integrated Flux = (T_left - T_right) * (gapK/(r^2*((1/r1)-(1/r2)))) * Area
#
# For gapK = 1 (default value)
#
# The area is taken as the area of the slave (inner) surface:
#
# Area = 4 * pi * 1^2 (4*pi*r^2)
#
# The integrated heat flux across the gap at time 1 is then:
#
# 4*pi*k*delta_T/((1/r1)-(1/r2))
# 4*pi*1*100/((1/1) - (1/2)) = 2513.3 watts
#
# For comparison, see results from the integrated flux post processors.
# This simulation makes use of symmetry, so only 1/8 of the spheres is meshed
# As such, the integrated flux from the post processors is 1/8 of the total,
# or 314.159 watts... i.e. 100*pi.
# The value coming from the post processor is slightly less than this
# but converges as mesh refinement increases.
#
# Simulating contact is challenging. Regression tests that exercise
# contact features can be difficult to solve consistently across multiple
# platforms. While designing these tests, we felt it worth while to note
# some aspects of these tests. The following applies to:
# sphere3D.i, sphere2DRZ.i, cyl2D.i, and cyl3D.i.
# 1. We decided that to perform consistently across multiple platforms we
# would use very small convergence tolerance. In this test we chose an
# nl_rel_tol of 1e-12.
# 2. Due to such a high value for thermal conductivity (used here so that the
# domains come to a uniform temperature) the integrated flux at time = 0
# was relatively large (the value coming from SideIntegralFlux =
# -_diffusion_coef[_qp]*_grad_u[_qp]*_normals[_qp] where the diffusion coefficient
# here is thermal conductivity).
# Even though _grad_u[_qp] is small, in this case the diffusion coefficient
# is large. The result is a number that isn't exactly zero and tends to
# fail exodiff. For this reason the parameter execute_on = initial should not
# be used. That parameter is left to default settings in these regression tests.
#
[GlobalParams]
order = SECOND
family = LAGRANGE
[]
[Mesh]
file = sphere3D.e
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1'
y = '100 200'
[../]
[]
[Variables]
[./temp]
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_conductance]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat_conduction]
type = HeatConduction
variable = temp
[../]
[]
[AuxKernels]
[./gap_cond]
type = MaterialRealAux
property = gap_conductance
variable = gap_conductance
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 100000000.0
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
gap_conductivity = 1
quadrature = true
gap_geometry_type = SPHERE
sphere_origin = '0 0 0'
[../]
[]
[BCs]
[./mid]
type = FunctionPresetBC
boundary = 5
variable = temp
function = temp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_factor_mat_solver_package'
petsc_options_value = 'lu superlu_dist'
dt = 1
dtmin = 0.01
end_time = 1
nl_rel_tol = 1e-12
nl_abs_tol = 1e-7
[./Quadrature]
order = fifth
side_order = seventh
[../]
[]
[Outputs]
exodus = true
[./Console]
type = Console
[../]
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/planar_xy.i

```
# 1-D Gap Heat Transfer Test without mechanics
#
# This test exercises 1-D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of two element blocks in the x-y plane. Each element block
# is a square. They sit next to one another with a unit between them.
#
# The conductivity of both blocks is set very large to achieve a uniform temperature
# across each block. The temperature of the far bottom boundary
# is ramped from 100 to 200 over one time unit. The temperature of the far top
# boundary is held fixed at 100.
#
# A simple analytical solution is possible for the heat flux between the blocks:
#
# Flux = (T_left - T_right) * (gapK/gap_width)
#
# The gap conductivity is specified as 1, thus
#
# gapK(Tavg) = 1.0*Tavg
#
# The heat flux across the gap at time = 1 is then:
#
# Flux = 100 * (1.0/1.0) = 100
#
# For comparison, see results from the flux post processors. These results
# are the same as for the unit 1-D gap heat transfer between two unit cubes.
[Mesh]
file = simple_2D.e
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1 2'
y = '100 200 200'
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
[../]
[]
[Variables]
[./temp]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_cond]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./temp_far_bottom]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_top]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[AuxKernels]
[./conductance]
type = MaterialRealAux
property = gap_conductance
variable = gap_cond
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 100000000.0
[../]
[./density]
type = Density
block = '1 2'
density = 1.0
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-ksp_gmres_restart -pc_type -pc_hypre_type -pc_hypre_boomeramg_max_iter'
petsc_options_value = '201 hypre boomeramg 4'
line_search = 'none'
nl_rel_tol = 1e-14
l_tol = 1e-3
l_max_its = 100
dt = 1e-1
end_time = 1.0
[]
[Postprocessors]
[./temp_bottom]
type = SideAverageValue
boundary = 2
variable = temp
execute_on = 'initial timestep_end'
[../]
[./temp_top]
type = SideAverageValue
boundary = 3
variable = temp
execute_on = 'initial timestep_end'
[../]
[./flux_bottom]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[./flux_top]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
execute_on = 'initial timestep_end'
[../]
[]
[Outputs]
exodus = true
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/gap_heat_transfer_htonly_it_plot_test.i

```
#
# 1-D Gap Heat Transfer Test without mechanics
#
# This test exercises 1-D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of two element blocks containing one element each. Each
# element is a unit cube. They sit next to one another with a unit between them.
#
# The conductivity of both blocks is set very large to achieve a uniform temperature
# across each block. The temperature of the far left boundary
# is ramped from 100 to 200 over one time unit, and then held fixed for an additional
# time unit. The temperature of the far right boundary is held fixed at 100.
#
# A simple analytical solution is possible for the heat flux between the blocks:
#
# Flux = (T_left - T_right) * (gapK/gap_width)
#
# The gap conductivity is specified as 1, thus
#
# gapK(Tavg) = 1.0*Tavg
#
#
# The heat flux across the gap at time = 2 is then:
#
# Flux(2) = 100 * (1.0/1.0) = 100
#
# For comparison, see results from the flux post processors
#
[Mesh]
file = gap_heat_transfer_htonly_test.e
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1 2'
y = '100 200 200'
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
[../]
[]
[Variables]
[./temp]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[]
[Kernels]
[./heat]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./temp_far_left]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 100000000.0
[../]
[./density]
type = Density
block = '1 2'
density = 1.0
[../]
[]
[Executioner]
type = Transient
#Preconditioned JFNK (default)
solve_type = 'PJFNK'
petsc_options_iname = '-ksp_gmres_restart -pc_type -pc_hypre_type -pc_hypre_boomeramg_max_iter'
petsc_options_value = '201 hypre boomeramg 4'
line_search = 'none'
nl_abs_tol = 1e-5
nl_rel_tol = 1e-12
l_tol = 1e-10
l_max_its = 100
start_time = 0.0
dt = 1e-1
end_time = 2.0
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
[Outputs]
file_base = out_it_plot
[./exodus]
type = Exodus
execute_on = 'initial timestep_end nonlinear'
nonlinear_residual_dt_divisor = 100
[../]
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/cyl2D.i

```
#
# 2D Cylindrical Gap Heat Transfer Test.
#
# This test exercises 2D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of an inner solid cylinder of radius = 1 unit, and outer
# hollow cylinder with an inner radius of 2 in the x-y plane. In other words,
# the gap between them is 1 radial unit in length.
#
# The conductivity of both cylinders is set very large to achieve a uniform
# temperature in each cylinder. The temperature of the center node of the
# inner cylinder is ramped from 100 to 200 over one time unit. The temperature
# of the outside of the outer, hollow cylinder is held fixed at 100.
#
# A simple analytical solution is possible for the integrated heat flux
# between the inner and outer cylinders:
#
# Integrated Flux = (T_left - T_right) * (gapK/(r*ln(r2/r1))) * Area
#
# For gapK = 1 (default value)
#
# The area is taken as the area of the slave (inner) surface:
#
# Area = 2 * pi * h * r, where h is the height of the cylinder.
#
# The integrated heat flux across the gap at time 1 is then:
#
# 2*pi*h*k*delta_T/(ln(r2/r1))
# 2*pi*1*1*100/(ln(2/1)) = 906.5 watts
#
# For comparison, see results from the integrated flux post processors.
# This simulation makes use of symmetry, so only 1/4 of the cylinders is meshed
# As such, the integrated flux from the post processors is 1/4 of the total,
# or 226.6 watts.
# The value coming from the post processor is slightly less than this
# but converges as mesh refinement increases.
# Note that the 2D and 3D results are the same.
#
# Simulating contact is challenging. Regression tests that exercise
# contact features can be difficult to solve consistently across multiple
# platforms. While designing these tests, we felt it worth while to note
# some aspects of these tests. The following applies to:
# sphere3D.i, sphere2DRZ.i, cyl2D.i, and cyl3D.i.
# 1. We decided that to perform consistently across multiple platforms we
# would use very small convergence tolerance. In this test we chose an
# nl_rel_tol of 1e-12.
# 2. Due to such a high value for thermal conductivity (used here so that the
# domains come to a uniform temperature) the integrated flux at time = 0
# was relatively large (the value coming from SideIntegralFlux =
# -_diffusion_coef[_qp]*_grad_u[_qp]*_normals[_qp] where the diffusion coefficient
# here is thermal conductivity).
# Even though _grad_u[_qp] is small, in this case the diffusion coefficient
# is large. The result is a number that isn't exactly zero and tends to
# fail exodiff. For this reason the parameter execute_on = initial should not
# be used. That parameter is left to default settings in these regression tests.
#
[GlobalParams]
order = SECOND
family = LAGRANGE
[]
[Mesh]
file = cyl2D.e
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1'
y = '100 200'
[../]
[]
[Variables]
[./temp]
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_conductance]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat_conduction]
type = HeatConduction
variable = temp
[../]
[]
[AuxKernels]
[./gap_cond]
type = MaterialRealAux
property = gap_conductance
variable = gap_conductance
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 1000000.0
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
gap_conductivity = 1
quadrature = true
gap_geometry_type = CYLINDER
cylinder_axis_point_1 = '0 0 0'
cylinder_axis_point_2 = '0 0 1'
[../]
[]
[BCs]
[./mid]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_factor_mat_solver_package'
petsc_options_value = 'lu superlu_dist'
dt = 1
dtmin = 0.01
end_time = 1
nl_rel_tol = 1e-12
nl_abs_tol = 1e-7
[./Quadrature]
order = fifth
side_order = seventh
[../]
[]
[Outputs]
exodus = true
[./Console]
type = Console
[../]
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/cyl2D_xz.i

```
#
# 2D Cylindrical Gap Heat Transfer Test.
#
# This test exercises 2D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of an inner solid cylinder of radius = 1 unit, and outer
# hollow cylinder with an inner radius of 2 in the x-z plane. In other words,
# the gap between them is 1 radial unit in length.
#
# The calculated results are the same as for the cyl2D.i case in the x-y plane.
[GlobalParams]
order = SECOND
family = LAGRANGE
[]
[Mesh]
file = cyl2D.e
[]
[MeshModifiers]
[./rotate]
type = Transform
transform = ROTATE
vector_value = '0 90 0'
[../]
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1'
y = '100 200'
[../]
[]
[Variables]
[./temp]
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_conductance]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat_conduction]
type = HeatConduction
variable = temp
[../]
[]
[AuxKernels]
[./gap_cond]
type = MaterialRealAux
property = gap_conductance
variable = gap_conductance
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 1000000.0
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
gap_conductivity = 1
quadrature = true
gap_geometry_type = CYLINDER
cylinder_axis_point_1 = '0 0 0'
cylinder_axis_point_2 = '0 1 0'
[../]
[]
[BCs]
[./mid]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_factor_mat_solver_package'
petsc_options_value = 'lu superlu_dist'
dt = 1
dtmin = 0.01
end_time = 1
nl_rel_tol = 1e-12
nl_abs_tol = 1e-7
[./Quadrature]
order = fifth
side_order = seventh
[../]
[]
[Outputs]
exodus = true
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/gap_heat_transfer_htonly_rz_test.i

```
#
# 2-D RZ Gap Heat Transfer Test without mechanics
#
# This test exercises 1-D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of two element blocks containing one element each. Each
# element is a unit cube. They sit next to one another with a unit between them.
#
# The conductivity of both blocks is set very large to achieve a uniform temperature
# across each block. The temperature of the far left boundary
# is ramped from 100 to 200 over one time unit, and then held fixed for an additional
# time unit. The temperature of the far right boundary is held fixed at 100.
#
# A simple analytical solution is possible for the heat flux between the blocks, or cylinders in the case of RZ.:
#
# Flux = (T_left - T_right) * (gapK/(r*ln(r2/r1)))
#
# For gapK = 1 (default value)
#
# The integrated heat flux across the gap at time 2 is then:
#
# 2*pi*h*k*delta_T/(ln(r2/r1))
# 2*pi*1*1*100/(ln(2/1)) = 906.5 watts
#
# For comparison, see results from the flux post processors.
#
# As a second test, use the rectilinear (parallel plate) form of the gap heat transfer.
#
# Flux = (T_left - T_right) * (gapK/gapL)
#
# For gapK = 1 (default value)
#
# The integrated heat flux across the gap at time 2 is then:
#
# 2*pi*h*k*delta_T/(1)
# 2*pi*1*1*100/(1) = 628.3 watts
#
# For comparison, see results from the flux post processors.
#
[Problem]
coord_type = RZ
rz_coord_axis = Y # this is modified through CLI args to test Z-R as opposed to R-Z
[]
[Mesh]
file = gap_heat_transfer_htonly_rz_test.e
[]
[MeshModifiers]
active = '' # this is modified through CLI args to test Z-R as opposed to R-Z
[rotate]
type = Transform
transform = ROTATE
vector_value = '90 0 0'
[]
[]
[Functions]
[./ramp]
type = PiecewiseLinear
x = '0 1 2'
y = '100 200 200'
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
[../]
[./thermal_contact2]
type = GapHeatTransfer
variable = temp2
master = 3
slave = 2
gap_geometry_type = PLATE
appended_property_name = 2
[../]
[]
[Variables]
[./temp]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[./temp2]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_cond]
order = CONSTANT
family = MONOMIAL
[../]
[./gap_cond2]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat]
type = HeatConduction
variable = temp
[../]
[./heat2]
type = HeatConduction
variable = temp2
[../]
[]
[BCs]
[./temp_far_left]
type = FunctionPresetBC
boundary = 1
variable = temp
function = ramp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[./temp_far_left2]
type = FunctionPresetBC
boundary = 1
variable = temp2
function = ramp
[../]
[./temp_far_right2]
type = PresetBC
boundary = 4
variable = temp2
value = 100
[../]
[]
[AuxKernels]
[./conductance]
type = MaterialRealAux
property = gap_conductance
variable = gap_cond
boundary = 2
[../]
[./conductance2]
type = MaterialRealAux
property = gap_conductance
variable = gap_cond2
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 1e6
[../]
[./density]
type = Density
block = '1 2'
density = 1.0
[../]
[]
[Executioner]
type = Transient
# petsc_options = '-snes_mf_operator -ksp_monitor -snes_ksp_ew'
#Preconditioned JFNK (default)
solve_type = 'PJFNK'
# petsc_options_iname = '-snes_type -snes_ls -snes_linesearch_type -ksp_gmres_restart -pc_type -pc_hypre_type -pc_hypre_boomeramg_max_iter'
# petsc_options_value = 'ls basic basic 201 hypre boomeramg 4'
# petsc_options_iname = '-ksp_gmres_restart -pc_type -pc_hypre_type -pc_hypre_boomeramg_max_iter'
# petsc_options_value = '201 hypre boomeramg 4'
nl_abs_tol = 1e-3
nl_rel_tol = 1e-8
l_tol = 1e-6
l_max_its = 100
start_time = 0.0
dt = 1e-1
dtmin = 1e-1
end_time = 2.0
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
execute_on = 'initial timestep_end'
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
execute_on = 'initial timestep_end'
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[./temp_left2]
type = SideAverageValue
boundary = 2
variable = temp2
execute_on = 'initial timestep_end'
[../]
[./temp_right2]
type = SideAverageValue
boundary = 3
variable = temp2
execute_on = 'initial timestep_end'
[../]
[./flux_left2]
type = SideFluxIntegral
variable = temp2
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right2]
type = SideFluxIntegral
variable = temp2
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
[Outputs]
exodus = true
[]
```

#### test/tests/postprocessors/misc_pps/misc_pps_test.i

```
[Mesh]
type = GeneratedMesh
dim = 2
xmin = -1
xmax = 1
ymin = -1
ymax = 1
nx = 10
ny = 10
elem_type = QUAD9
[]
[Variables]
[./u]
order = SECOND
family = LAGRANGE
[../]
[]
[AuxVariables]
[./aux_var]
family = SCALAR
initial_condition = 42
[../]
[]
[Functions]
[./forcing_fn]
type = ParsedFunction
value = 3*t*t*((x*x)+(y*y))-(4*t*t*t)
[../]
[./exact_fn]
type = ParsedFunction
value = t*t*t*((x*x)+(y*y))
[../]
[]
[Kernels]
[./ie]
type = TimeDerivative
variable = u
[../]
[./diff]
type = Diffusion
variable = u
[../]
[./ffn]
type = BodyForce
variable = u
function = forcing_fn
[../]
[]
[BCs]
active = 'all'
[./all]
type = FunctionDirichletBC
variable = u
boundary = '0 1 2 3'
function = exact_fn
[../]
[./left]
type = DirichletBC
variable = u
boundary = 3
value = 0
[../]
[./right]
type = DirichletBC
variable = u
boundary = 1
value = 1
[../]
[]
[Postprocessors]
# Should be zero since we aren't setting this inside any MooseObject
# This PPS will also always report zero in this test
[./num_nonlinear_its]
type = NumNonlinearIterations
[../]
[./num_linear_its]
type = NumLinearIterations
[../]
[./residual]
type = Residual
[../]
[./reporter]
type = ScalarVariable
variable = aux_var
[../]
[./empty]
type = EmptyPostprocessor
[../]
[./side_flux_integral]
type = SideFluxIntegral
diffusivity = diffusivity
variable = u
boundary = 2 # top
[../]
[]
[Materials]
[./constant_block]
type = GenericConstantMaterial
prop_names = diffusivity
prop_values = 1
block = 0
[../]
[]
[Executioner]
type = Transient
scheme = implicit-euler
solve_type = PJFNK
start_time = 0.0
num_steps = 10
dt = 0.25
[]
[Outputs]
file_base = pps_out
exodus = true
[]
```

#### modules/functional_expansion_tools/test/tests/standard_use/interface_coupled.i

```
[Mesh]
type = GeneratedMesh
dim = 2
xmin = 0.0
xmax = 0.4
nx = 6
ymin = 0.0
ymax = 10.0
ny = 20
[]
[Variables]
[./m]
[../]
[]
[Kernels]
[./diff_m]
type = Diffusion
variable = m
[../]
[./time_diff_m]
type = TimeDerivative
variable = m
[../]
[./source_m]
type = BodyForce
variable = m
value = 100
[../]
[]
[ICs]
[./start_m]
type = ConstantIC
value = 2
variable = m
[../]
[]
[BCs]
[./interface_value]
type = FXValueBC
variable = m
boundary = right
function = FX_Basis_Value_Main
[../]
[./interface_flux]
type = FXFluxBC
boundary = right
variable = m
function = FX_Basis_Flux_Main
[../]
[]
[Functions]
[./FX_Basis_Value_Main]
type = FunctionSeries
series_type = Cartesian
orders = '4'
physical_bounds = '0.0 10'
y = Legendre
[../]
[./FX_Basis_Flux_Main]
type = FunctionSeries
series_type = Cartesian
orders = '5'
physical_bounds = '0.0 10'
y = Legendre
[../]
[]
[UserObjects]
[./FX_Flux_UserObject_Main]
type = FXBoundaryFluxUserObject
function = FX_Basis_Flux_Main
variable = m
boundary = right
diffusivity = 0.1
[../]
[]
[Postprocessors]
[./average_interface_value]
type = SideAverageValue
variable = m
boundary = right
[../]
[./total_flux]
type = SideFluxIntegral
variable = m
boundary = right
diffusivity = 0.1
[../]
[./picard_iterations]
type = NumPicardIterations
execute_on = 'initial timestep_end'
[../]
[]
[Executioner]
type = Transient
num_steps = 4
dt = 1.0
solve_type = PJFNK
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
picard_max_its = 30
nl_rel_tol = 1e-8
nl_abs_tol = 1e-9
picard_rel_tol = 1e-8
picard_abs_tol = 1e-9
[]
[Outputs]
exodus = true
[]
[MultiApps]
[./FXTransferApp]
type = TransientMultiApp
input_files = interface_sub.i
sub_cycling = true
[../]
[]
[Transfers]
[./FluxToSub]
type = MultiAppFXTransfer
direction = to_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Flux_UserObject_Main
multi_app_object_name = FX_Basis_Flux_Sub
[../]
[./ValueToMe]
type = MultiAppFXTransfer
direction = from_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Basis_Value_Main
multi_app_object_name = FX_Value_UserObject_Sub
[../]
[./FluxToMe]
type = MultiAppFXTransfer
direction = from_multiapp
multi_app = FXTransferApp
this_app_object_name = FX_Basis_Flux_Main
multi_app_object_name = FX_Flux_UserObject_Sub
[../]
[]
```

#### modules/combined/test/tests/gap_heat_transfer_radiation/gap_heat_transfer_radiation_test.i

```
#
# 1-D Gap Heat Transfer Test without mechanics
#
# This test exercises 1-D gap heat transfer for a helium-filled gap including radiation.
#
# The mesh consists of two element blocks containing one element each. Each
# element is a unit cube. They sit next to one another with a unit between them.
#
# The conductivity of both blocks is set very large to achieve a uniform temperature
# across each block. The temperature of the far left boundary
# is ramped from 100 to 200 over one time unit, and then held fixed for an additional
# time unit. The temperature of the far right boundary is held fixed at 100.
#
# A simple analytical solution is possible for the heat flux between the blocks:
#
# Flux = (T_left - T_right) * h_gap
#
# where h_gap = h_gas + h_cont + h_rad
#
# By setting the contact pressure, roughnesses, and jump distances to zero, the gap
# conductance simplifies to:
#
# h_gap = gapK/d_gap + sigma*Fe*(T_left^2 + T_right^2)*(T_left + T_right)
#
# where Fe = 1/(1/eps_left + 1/eps_right - 1)
# eps = emissivity
#
# For pure helium, BISON computes the gas conductivity as:
#
# gapK(Tavg) = 2.639e-3*Tavg^0.7085
#
# For the test, the final (t=2) average gas temperature is (200 +100)/2 = 150,
# giving gapK(150) = 0.09187557
#
# Assuming ems_left = ems_right = 0.5, Fe = 1/3
#
# The heat flux across the gap at that time is then:
#
# Flux(2) = 100 * ((0.09187557/1.0) + (5.669e-8/3)*(200^2 + 100^2)*(200 + 100))
# = 37.532557
#
# The flux post processors give 37.53255
#
[Mesh]
file = gap_heat_transfer_radiation_test.e
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1'
y = '200 200'
[../]
[]
[Variables]
[./temp]
order = FIRST
family = LAGRANGE
initial_condition = 100
[../]
[]
[Kernels]
[./heat]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./temp_far_left]
type = FunctionDirichletBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_right]
type = DirichletBC
boundary = 4
variable = temp
value = 100
[../]
[]
[ThermalContact]
[./gap]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
gap_conductivity = 0.09187557
emissivity_1 = 0.5
emissivity_2 = 0.5
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 10000000.0
[../]
[./density]
type = Density
block = '1 2'
density = 1.0
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-ksp_gmres_restart -pc_type -pc_hypre_type -pc_hypre_boomeramg_max_iter'
petsc_options_value = '201 hypre boomeramg 4'
line_search = 'none'
nl_abs_tol = 1e-6
nl_rel_tol = 1e-10
l_tol = 1e-3
l_max_its = 100
start_time = 0.0
dt = 1
end_time = 1.0
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
execute_on = 'initial timestep_end'
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
execute_on = 'initial timestep_end'
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
[Outputs]
exodus = true
[]
```

#### modules/heat_conduction/test/tests/heat_conduction/3d_quadrature_gap_heat_transfer/nonmatching.i

```
[Mesh]
file = nonmatching.e
[]
[Variables]
[./temp]
[../]
[]
[Kernels]
[./hc]
type = HeatConduction
variable = temp
[../]
[]
[BCs]
[./left]
type = DirichletBC
variable = temp
boundary = leftleft
value = 1000
[../]
[./right]
type = DirichletBC
variable = temp
boundary = rightright
value = 400
[../]
[]
[ThermalContact]
[./left_to_right]
slave = leftright
quadrature = true
master = rightleft
variable = temp
type = GapHeatTransfer
[../]
[]
[Materials]
[./hcm]
type = HeatConductionMaterial
block = 'left right'
specific_heat = 1
thermal_conductivity = 1
[../]
[]
[Postprocessors]
[./left]
type = SideFluxIntegral
variable = temp
boundary = leftright
diffusivity = thermal_conductivity
[../]
[./right]
type = SideFluxIntegral
variable = temp
boundary = rightleft
diffusivity = thermal_conductivity
[../]
[]
[Executioner]
type = Steady
#Preconditioned JFNK (default)
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_hypre_type'
petsc_options_value = 'hypre boomeramg'
[]
[Outputs]
exodus = true
[]
```

#### modules/combined/test/tests/gap_heat_transfer_htonly/sphere2DRZ.i

```
#
# 2DRZ Spherical Gap Heat Transfer Test.
#
# This test exercises 2D gap heat transfer for a constant conductivity gap.
#
# The mesh consists of an inner solid sphere of radius = 1 unit, and outer
# hollow sphere with an inner radius of 2. In other words, the gap between
# them is 1 radial unit in length.
#
# The conductivity of both spheres is set very large to achieve a uniform
# temperature in each sphere. The temperature of the center node of the
# inner sphere is ramped from 100 to 200 over one time unit. The
# temperature of the outside of the outer, hollow sphere is held fixed
# at 100.
#
# A simple analytical solution is possible for the integrated heat flux
# between the inner and outer spheres:
#
# Integrated Flux = (T_left - T_right) * (gapK/(r^2*((1/r1)-(1/r2)))) * Area
#
# For gapK = 1 (default value)
#
# The area is taken as the area of the slave (inner) surface:
#
# Area = 4 * pi * 1^2 (4*pi*r^2)
#
# The integrated heat flux across the gap at time 1 is then:
#
# 4*pi*k*delta_T/((1/r1)-(1/r2))
# 4*pi*1*100/((1/1) - (1/2)) = 2513.3 watts
#
# For comparison, see results from the integrated flux post processors.
# This simulation makes use of symmetry, so only 1/2 of the spheres is meshed
# As such, the integrated flux from the post processors is 1/2 of the total,
# or 1256.6 watts... i.e. 400*pi.
# The value coming from the post processor is slightly less than this
# but converges as mesh refinement increases.
#
# Simulating contact is challenging. Regression tests that exercise
# contact features can be difficult to solve consistently across multiple
# platforms. While designing these tests, we felt it worth while to note
# some aspects of these tests. The following applies to:
# sphere3D.i, sphere2DRZ.i, cyl2D.i, and cyl3D.i.
# 1. We decided that to perform consistently across multiple platforms we
# would use very small convergence tolerance. In this test we chose an
# nl_rel_tol of 1e-12.
# 2. Due to such a high value for thermal conductivity (used here so that the
# domains come to a uniform temperature) the integrated flux at time = 0
# was relatively large (the value coming from SideIntegralFlux =
# -_diffusion_coef[_qp]*_grad_u[_qp]*_normals[_qp] where the diffusion coefficient
# here is thermal conductivity).
# Even though _grad_u[_qp] is small, in this case the diffusion coefficient
# is large. The result is a number that isn't exactly zero and tends to
# fail exodiff. For this reason the parameter execute_on = initial should not
# be used. That parameter is left to default settings in these regression tests.
#
[GlobalParams]
order = SECOND
family = LAGRANGE
[]
[Problem]
coord_type = RZ
[]
[Mesh]
file = cyl2D.e
[]
[Functions]
[./temp]
type = PiecewiseLinear
x = '0 1'
y = '100 200'
[../]
[]
[Variables]
[./temp]
initial_condition = 100
[../]
[]
[AuxVariables]
[./gap_conductance]
order = CONSTANT
family = MONOMIAL
[../]
[]
[Kernels]
[./heat_conduction]
type = HeatConduction
variable = temp
[../]
[]
[AuxKernels]
[./gap_cond]
type = MaterialRealAux
property = gap_conductance
variable = gap_conductance
boundary = 2
[../]
[]
[Materials]
[./heat1]
type = HeatConductionMaterial
block = '1 2'
specific_heat = 1.0
thermal_conductivity = 1000000.0
[../]
[]
[ThermalContact]
[./thermal_contact]
type = GapHeatTransfer
variable = temp
master = 3
slave = 2
gap_conductivity = 1
quadrature = true
gap_geometry_type = SPHERE
sphere_origin = '0 0 0'
[../]
[]
[BCs]
[./mid]
type = FunctionPresetBC
boundary = 1
variable = temp
function = temp
[../]
[./temp_far_right]
type = PresetBC
boundary = 4
variable = temp
value = 100
[../]
[]
[Executioner]
type = Transient
solve_type = 'PJFNK'
petsc_options_iname = '-pc_type -pc_factor_mat_solver_package'
petsc_options_value = 'lu superlu_dist'
dt = 1
dtmin = 0.01
end_time = 1
nl_rel_tol = 1e-12
nl_abs_tol = 1e-7
[./Quadrature]
order = fifth
side_order = seventh
[../]
[]
[Outputs]
exodus = true
[./Console]
type = Console
[../]
[]
[Postprocessors]
[./temp_left]
type = SideAverageValue
boundary = 2
variable = temp
[../]
[./temp_right]
type = SideAverageValue
boundary = 3
variable = temp
[../]
[./flux_left]
type = SideFluxIntegral
variable = temp
boundary = 2
diffusivity = thermal_conductivity
[../]
[./flux_right]
type = SideFluxIntegral
variable = temp
boundary = 3
diffusivity = thermal_conductivity
[../]
[]
```

## Child Objects

#### framework/include/postprocessors/SideFluxAverage.h

```
// This file is part of the MOOSE framework
// https://www.mooseframework.org
//
// All rights reserved, see COPYRIGHT for full restrictions
// https://github.com/idaholab/moose/blob/master/COPYRIGHT
//
// Licensed under LGPL 2.1, please see LICENSE for details
// https://www.gnu.org/licenses/lgpl-2.1.html
#ifndef SIDEFLUXAVERAGE_H
#define SIDEFLUXAVERAGE_H
#include "SideFluxIntegral.h"
// Forward Declarations
class SideFluxAverage;
template <>
InputParameters validParams<SideFluxAverage>();
class SideFluxAverage : public SideFluxIntegral
{
public:
SideFluxAverage(const InputParameters & parameters);
virtual void initialize() override;
virtual void execute() override;
virtual Real getValue() override;
virtual void threadJoin(const UserObject & y) override;
protected:
Real _volume;
};
#endif
```