PressureDrop

Computes the pressure drop between an upstream and a downstream boundary.

The convention used is that if the pressure is decreasing from the upstream to downstream boundaries, then the pressure drop is positive.

note

If using mesh refinement, and if the upstream and downstream boundary are touching, the boundary between the two may not lie within a refined element, on a node inside a refined side.

Using a weighting functor on local pressures

The weighting functor, a vector, is dotted with the normal of the boundary and can help compute more representative pressure drops for the cases of non-constant pressure profiles across a boundary or for handling multiple upstream/downstream boundaries. This is effectively a weighting flux, which should usually be set to a momentum functor so that the effective weighting factor is the local mass flux.

$var element = document.getElementById("moose-equation-eec7f7b2-92a2-4658-b1bd-31e952ee906f");katex.render("\\begin{split} P_{upstream} &= \\dfrac{\\int_{\\delta \\Omega} P(x,y,z) \\vec{W}(x,y,z) \\cdot \\vec{n} }{ \\int_{\\delta \\Omega} \\vec{W}(x,y,z) \\cdot \\vec{n} } \\\\ P_{downstream} &= \\ ... \\\\ P_{drop} &= P_{upstream} - P_{downstream} \\end{split}", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$

where $var element = document.getElementById("moose-equation-5409ad1e-7b29-4edd-b7f0-caa2ec542030");katex.render("\\delta \\Omega", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the boundary (upstream or downstream) of interest for each pressure evaluation, $var element = document.getElementById("moose-equation-444541f0-1c12-4d9c-99f1-9f30132b0f59");katex.render("P", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the local pressure (on the element side on the boundary for finite volume variables), $var element = document.getElementById("moose-equation-2814ba81-949a-4694-ab7b-f373c5d016f4");katex.render("\\vec{W}", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the vector weighting functor and $var element = document.getElementById("moose-equation-a140b154-7b4c-4340-8d9e-2eb7d170be04");katex.render("\\vec{n}", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the local element side normal.

Example input syntax

In this example, we measure the pressure drop between the inlet and outlet of a flow channel, as well as between the inlet and a midsection.

[Postprocessors<<<{"href": "../../syntax/Postprocessors/index.html"}>>>]
  [pdrop_total]
    type = PressureDrop<<<{"description": "Computes the pressure drop between an upstream and a downstream boundary.", "href": "PressureDrop.html"}>>>
    pressure<<<{"description": "The pressure functor. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number."}>>> = pressure
    upstream_boundary<<<{"description": "The upstream surface (must also be specified in 'boundary' parameter"}>>> = 'bottom'
    downstream_boundary<<<{"description": "The downstream surface (must also be specified in 'boundary' parameter"}>>> = 'top'
    boundary<<<{"description": "The list of boundary IDs from the mesh where this object applies"}>>> = 'top bottom'
  []
  [pdrop_mid1]
    type = PressureDrop<<<{"description": "Computes the pressure drop between an upstream and a downstream boundary.", "href": "PressureDrop.html"}>>>
    pressure<<<{"description": "The pressure functor. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number."}>>> = pressure
    upstream_boundary<<<{"description": "The upstream surface (must also be specified in 'boundary' parameter"}>>> = 'bottom'
    downstream_boundary<<<{"description": "The downstream surface (must also be specified in 'boundary' parameter"}>>> = 'internal_bot'
    boundary<<<{"description": "The list of boundary IDs from the mesh where this object applies"}>>> = 'bottom internal_bot'
  []
  [pdrop_mid2]
    type = PressureDrop<<<{"description": "Computes the pressure drop between an upstream and a downstream boundary.", "href": "PressureDrop.html"}>>>
    pressure<<<{"description": "The pressure functor. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number."}>>> = pressure
    upstream_boundary<<<{"description": "The upstream surface (must also be specified in 'boundary' parameter"}>>> = 'internal_bot'
    downstream_boundary<<<{"description": "The downstream surface (must also be specified in 'boundary' parameter"}>>> = 'internal_top'
    boundary<<<{"description": "The list of boundary IDs from the mesh where this object applies"}>>> = 'internal_top internal_bot'
  []
  [pdrop_mid3]
    type = PressureDrop<<<{"description": "Computes the pressure drop between an upstream and a downstream boundary.", "href": "PressureDrop.html"}>>>
    pressure<<<{"description": "The pressure functor. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number."}>>> = pressure
    upstream_boundary<<<{"description": "The upstream surface (must also be specified in 'boundary' parameter"}>>> = 'internal_top'
    downstream_boundary<<<{"description": "The downstream surface (must also be specified in 'boundary' parameter"}>>> = 'top'
    boundary<<<{"description": "The list of boundary IDs from the mesh where this object applies"}>>> = 'top internal_top'
  []
  [sum_drops]
    type = ParsedPostprocessor<<<{"description": "Computes a parsed expression with post-processors", "href": "ParsedPostprocessor.html"}>>>
    expression<<<{"description": "function expression"}>>> = 'pdrop_mid1 + pdrop_mid2 + pdrop_mid3'
    pp_names<<<{"description": "Post-processors arguments"}>>> = 'pdrop_mid1 pdrop_mid2 pdrop_mid3'
  []

  [p_upstream]
    type = SideAverageValue<<<{"description": "Computes the average value of a variable on a sideset. Note that this cannot be used on the centerline of an axisymmetric model.", "href": "SideAverageValue.html"}>>>
    variable<<<{"description": "The name of the variable which this postprocessor integrates"}>>> = pressure
    boundary<<<{"description": "The list of boundary IDs from the mesh where this object applies"}>>> = 'bottom'
  []
  [p_downstream]
    type = SideAverageValue<<<{"description": "Computes the average value of a variable on a sideset. Note that this cannot be used on the centerline of an axisymmetric model.", "href": "SideAverageValue.html"}>>>
    variable<<<{"description": "The name of the variable which this postprocessor integrates"}>>> = pressure
    boundary<<<{"description": "The list of boundary IDs from the mesh where this object applies"}>>> = 'top'
  []
[]

Input Parameters

boundaryThe list of boundary IDs from the mesh where this object applies
C++ Type:std::vector<BoundaryName>
Controllable:No
Description:The list of boundary IDs from the mesh where this object applies
downstream_boundaryThe downstream surface (must also be specified in 'boundary' parameter
C++ Type:std::vector<BoundaryName>
Controllable:No
Description:The downstream surface (must also be specified in 'boundary' parameter
pressureThe pressure functor. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number.
C++ Type:MooseFunctorName
Unit:(no unit assumed)
Controllable:No
Description:The pressure functor. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number.
upstream_boundaryThe upstream surface (must also be specified in 'boundary' parameter
C++ Type:std::vector<BoundaryName>
Controllable:No
Description:The upstream surface (must also be specified in 'boundary' parameter

Required Parameters

weighting_functorA vector functor to compute a flux to weigh the pressure for the pressure average computations. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number.
C++ Type:MooseFunctorName
Unit:(no unit assumed)
Controllable:No
Description:A vector functor to compute a flux to weigh the pressure for the pressure average computations. A functor is any of the following: a variable, a functor material property, a function, a postprocessor or a number.
weighting_interp_methodupwindThe interpolation to use for the weighting functor.
Default:upwind
C++ Type:MooseEnum
Options:average, upwind, sou, min_mod, vanLeer, quick, venkatakrishnan, skewness-corrected
Controllable:No
Description:The interpolation to use for the weighting functor.

Optional Parameters

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
Controllable:No
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).
execute_onTIMESTEP_ENDThe list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.
Default:TIMESTEP_END
C++ Type:ExecFlagEnum
Options:XFEM_MARK, FORWARD, ADJOINT, HOMOGENEOUS_FORWARD, ADJOINT_TIMESTEP_BEGIN, ADJOINT_TIMESTEP_END, NONE, INITIAL, LINEAR, LINEAR_CONVERGENCE, NONLINEAR, NONLINEAR_CONVERGENCE, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, MULTIAPP_FIXED_POINT_CONVERGENCE, FINAL, CUSTOM, TRANSFER
Controllable:No
Description:The list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.
execution_order_group0Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.
Default:0
C++ Type:int
Controllable:No
Description:Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.
force_postauxFalseForces the UserObject to be executed in POSTAUX
Default:False
C++ Type:bool
Controllable:No
Description:Forces the UserObject to be executed in POSTAUX
force_preauxFalseForces the UserObject to be executed in PREAUX
Default:False
C++ Type:bool
Controllable:No
Description:Forces the UserObject to be executed in PREAUX
force_preicFalseForces the UserObject to be executed in PREIC during initial setup
Default:False
C++ Type:bool
Controllable:No
Description:Forces the UserObject to be executed in PREIC during initial setup

Execution Scheduling Parameters

control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Controllable:No
Description:Adds user-defined labels for accessing object parameters via control logic.
enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Controllable:Yes
Description:Set the enabled status of the MooseObject.
outputsVector of output names where you would like to restrict the output of variables(s) associated with this object
C++ Type:std::vector<OutputName>
Controllable:No
Description:Vector of output names where you would like to restrict the output of variables(s) associated with this object
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
Controllable:No
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

prop_getter_suffixAn optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.
C++ Type:MaterialPropertyName
Unit:(no unit assumed)
Controllable:No
Description:An optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.
use_interpolated_stateFalseFor the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.
Default:False
C++ Type:bool
Controllable:No
Description:For the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.

Material Property Retrieval Parameters

Input Files

(modules/navier_stokes/test/tests/finite_volume/two_phase/mixture_model/channel-drift-flux-physics.i)
(modules/navier_stokes/test/tests/finite_volume/ins/channel-flow/friction/2d-rc-friction-standard-linear-physics.i)
(modules/navier_stokes/test/tests/finite_volume/two_phase/mixture_model/segregated/channel-drift-flux.i)
(modules/navier_stokes/test/tests/finite_volume/two_phase/mixture_model/segregated/channel-drift-flux-physics.i)
(modules/navier_stokes/test/tests/finite_volume/materials/flow_diode/transient_operation.i)
(modules/navier_stokes/test/tests/postprocessors/pressure_drop/drop_insad.i)
(modules/navier_stokes/test/tests/finite_volume/ins/channel-flow/friction/2d-rc-friction-standard-nonlinear-physics.i)
(modules/navier_stokes/test/tests/postprocessors/pressure_drop/drop_insfv.i)

(modules/navier_stokes/test/tests/postprocessors/pressure_drop/drop_insfv.i)

mu=1
rho=1
advected_interp_method='average'
velocity_interp_method='rc'

[GlobalParams]
  rhie_chow_user_object = 'rc'
  advected_interp_method = ${advected_interp_method}
  velocity_interp_method = ${velocity_interp_method}
[]

[UserObjects]
  [rc]
    type = INSFVRhieChowInterpolator
    u = u
    v = v
    pressure = pressure
  []
[]

[Mesh]
  inactive = 'mesh internal_boundary_bot internal_boundary_top'
  [mesh]
    type = CartesianMeshGenerator
    dim = 2
    dx = '1'
    dy = '1 1 1'
    ix = '5'
    iy = '5 5 5'
    subdomain_id = '1
                    2
                    3'
  []
  [internal_boundary_bot]
    type = SideSetsBetweenSubdomainsGenerator
    input = mesh
    new_boundary = 'internal_bot'
    primary_block = 1
    paired_block = 2
  []
  [internal_boundary_top]
    type = SideSetsBetweenSubdomainsGenerator
    input = internal_boundary_bot
    new_boundary = 'internal_top'
    primary_block = 2
    paired_block = 3
  []
  [diverging_mesh]
    type = FileMeshGenerator
    file = 'expansion_quad.e'
  []
[]

[Variables]
  [u]
    type = INSFVVelocityVariable
    initial_condition = 0
  []
  [v]
    type = INSFVVelocityVariable
    initial_condition = 1
  []
  [pressure]
    type = INSFVPressureVariable
  []
  [temperature]
    type = INSFVEnergyVariable
  []
[]

[AuxVariables]
  [advected_density]
    type = MooseVariableFVReal
    initial_condition = ${rho}
  []
[]

[FVKernels]
  [mass]
    type = INSFVMassAdvection
    variable = pressure
    rho = ${rho}
  []

  [u_advection]
    type = INSFVMomentumAdvection
    variable = u
    rho = ${rho}
    momentum_component = 'x'
  []
  [u_viscosity]
    type = INSFVMomentumDiffusion
    variable = u
    mu = ${mu}
    force_boundary_execution = true
    momentum_component = 'x'
  []
  [u_pressure]
    type = INSFVMomentumPressure
    variable = u
    momentum_component = 'x'
    pressure = pressure
  []

  [v_advection]
    type = INSFVMomentumAdvection
    variable = v
    rho = ${rho}
    momentum_component = 'y'
  []
  [v_viscosity]
    type = INSFVMomentumDiffusion
    variable = v
    mu = ${mu}
    force_boundary_execution = true
    momentum_component = 'y'
  []
  [v_pressure]
    type = INSFVMomentumPressure
    variable = v
    momentum_component = 'y'
    pressure = pressure
  []

  [temp_advection]
    type = INSFVEnergyAdvection
    variable = temperature
    advected_interp_method = 'upwind'
  []
  [temp_source]
    type = FVBodyForce
    variable = temperature
    function = 10
    block = 1
  []
[]

[FVBCs]
  [inlet-u]
    type = INSFVInletVelocityBC
    boundary = 'bottom'
    variable = u
    function = 0
  []
  [inlet-v]
    type = INSFVInletVelocityBC
    boundary = 'bottom'
    variable = v
    function = 1
  []
  [noslip-u]
    type = INSFVNoSlipWallBC
    boundary = 'right'
    variable = u
    function = 0
  []
  [noslip-v]
    type = INSFVNoSlipWallBC
    boundary = 'right'
    variable = v
    function = 0
  []
  [axis-u]
    type = INSFVSymmetryVelocityBC
    boundary = 'left'
    variable = u
    u = u
    v = v
    mu = ${mu}
    momentum_component = x
  []
  [axis-v]
    type = INSFVSymmetryVelocityBC
    boundary = 'left'
    variable = v
    u = u
    v = v
    mu = ${mu}
    momentum_component = y
  []
  [axis-p]
    type = INSFVSymmetryPressureBC
    boundary = 'left'
    variable = pressure
  []
  [outlet_p]
    type = INSFVOutletPressureBC
    boundary = 'top'
    variable = pressure
    function = 0
  []
  [inlet_temp]
    type = FVNeumannBC
    boundary = 'bottom'
    variable = temperature
    value = 300
  []
[]

[FunctorMaterials]
  [ins_fv]
    type = INSFVEnthalpyFunctorMaterial
    temperature = 'temperature'
    rho = ${rho}
  []
  [advected_material_property]
    type = ADGenericFunctorMaterial
    prop_names = 'advected_rho cp'
    prop_values ='${rho} 1'
  []
  [vel_functor]
    type = ADGenericVectorFunctorMaterial
    prop_names = 'velocity'
    prop_values = 'u v 0'
  []
[]

[Executioner]
  type = Steady
  solve_type = 'NEWTON'
  petsc_options_iname = '-pc_type -ksp_gmres_restart -sub_pc_type -sub_pc_factor_shift_type'
  petsc_options_value = 'asm      200                lu           NONZERO'
  line_search = 'none'
  nl_rel_tol = 1e-12
[]

[Postprocessors]
  [pdrop_total]
    type = PressureDrop
    pressure = pressure
    upstream_boundary = 'bottom'
    downstream_boundary = 'top'
    boundary = 'top bottom'
  []
  [pdrop_mid1]
    type = PressureDrop
    pressure = pressure
    upstream_boundary = 'bottom'
    downstream_boundary = 'internal_bot'
    boundary = 'bottom internal_bot'
  []
  [pdrop_mid2]
    type = PressureDrop
    pressure = pressure
    upstream_boundary = 'internal_bot'
    downstream_boundary = 'internal_top'
    boundary = 'internal_top internal_bot'
  []
  [pdrop_mid3]
    type = PressureDrop
    pressure = pressure
    upstream_boundary = 'internal_top'
    downstream_boundary = 'top'
    boundary = 'top internal_top'
  []
  [sum_drops]
    type = ParsedPostprocessor
    expression = 'pdrop_mid1 + pdrop_mid2 + pdrop_mid3'
    pp_names = 'pdrop_mid1 pdrop_mid2 pdrop_mid3'
  []

  [p_upstream]
    type = SideAverageValue
    variable = pressure
    boundary = 'bottom'
  []
  [p_downstream]
    type = SideAverageValue
    variable = pressure
    boundary = 'top'
  []
[]

[Outputs]
  csv = true
[]

(modules/navier_stokes/test/tests/finite_volume/two_phase/mixture_model/channel-drift-flux-physics.i)

mu = 1.0
rho = 10.0
mu_d = 0.1
rho_d = 1.0
l = 2
U = 1
dp = 0.01
inlet_phase_2 = 0.1
advected_interp_method = 'average'
velocity_interp_method = 'rc'

# TODO remove need for those
cp = 1
k = 1
cp_d = 1
k_d = 1

[Mesh]
  [gen]
    type = GeneratedMeshGenerator
    dim = 2
    xmin = 0
    xmax = '${fparse l * 5}'
    ymin = '${fparse -l / 2}'
    ymax = '${fparse l / 2}'
    nx = 10
    ny = 4
  []
  uniform_refine = 0
[]

[Physics]
  [NavierStokes]
    [Flow]
      [flow]
        compressibility = 'incompressible'

        density = 'rho_mixture'
        dynamic_viscosity = 'mu_mixture'

        # Initial conditions
        initial_velocity = '0 0 0'
        initial_pressure = 0

        # Boundary conditions
        inlet_boundaries = 'left'
        momentum_inlet_types = 'fixed-velocity'
        momentum_inlet_functors = '${U} 0'

        wall_boundaries = 'top bottom'
        momentum_wall_types = 'noslip noslip'

        outlet_boundaries = 'right'
        momentum_outlet_types = 'fixed-pressure'
        pressure_functors = '0'

        # Friction is done in drift flux term
        friction_types = "Darcy"
        friction_coeffs = "Darcy_coefficient_vec"
        standard_friction_formulation = true

        mass_advection_interpolation = '${advected_interp_method}'
        momentum_advection_interpolation = '${advected_interp_method}'
        velocity_interpolation = '${velocity_interp_method}'
        mu_interp_method = 'average'
      []
    []
    [TwoPhaseMixture]
      [mixture]
        phase_1_fraction_name = 'phase_1'
        phase_2_fraction_name = 'phase_2'

        # Phase transport equation
        add_phase_transport_equation = true
        alpha_exchange = 0.1
        phase_advection_interpolation = 'upwind'

        # see flow for inlet boundaries
        phase_fraction_inlet_type = 'fixed-value'
        phase_fraction_inlet_functors = '${inlet_phase_2}'

        # Needed for some reason
        ghost_layers = 5

        # Drift flux parameters
        add_drift_flux_momentum_terms = true
        density_interp_method = 'average'
        # This has to be consistent with the friction model
        slip_linear_friction_name = 'Darcy_coefficient'

        # Base phase material properties
        phase_1_density_name = ${rho}
        phase_1_viscosity_name = ${mu}
        phase_1_specific_heat_name = ${cp}
        phase_1_thermal_conductivity_name = ${k}

        # Not used because the 'slip_linear_friction_name' is set
        use_dispersed_phase_drag_model = true
        particle_diameter = ${dp}

        # Other phase material properties
        phase_2_density_name = ${rho_d}
        phase_2_viscosity_name = ${mu_d}
        phase_2_specific_heat_name = ${cp_d}
        phase_2_thermal_conductivity_name = ${k_d}
        output_all_properties = true
      []
    []
  []
[]

[Executioner]
  type = Steady
  solve_type = 'NEWTON'
  nl_rel_tol = 1e-10
[]

[Preconditioning]
  [SMP]
    type = SMP
    full = true
    petsc_options_iname = '-pc_type -pc_factor_shift_type'
    petsc_options_value = 'lu       NONZERO'
  []
[]

[Outputs]
  print_linear_residuals = true
  print_nonlinear_residuals = true
  dofmap = true
  [out]
    type = Exodus
    hide = 'Re lin cum_lin dp'
  []
  [perf]
    type = PerfGraphOutput
  []
[]

[Postprocessors]
  [Re]
    type = ParsedPostprocessor
    expression = '${rho} * ${l} * ${U}'
  []
  [lin]
    type = NumLinearIterations
  []
  [cum_lin]
    type = CumulativeValuePostprocessor
    postprocessor = lin
  []
  [dp]
    type = PressureDrop
    pressure = 'pressure'
    upstream_boundary = 'left'
    downstream_boundary = 'right'
    boundary = 'left right'
  []
[]

(modules/navier_stokes/test/tests/finite_volume/ins/channel-flow/friction/2d-rc-friction-standard-linear-physics.i)

mu = 1.1
rho = 1.1

[Mesh]
  [gen]
    type = GeneratedMeshGenerator
    dim = 2
    xmin = 0
    xmax = 5
    ymin = -1
    ymax = 1
    nx = 50
    ny = 10
  []
[]

[Physics]
  [NavierStokes]
    [FlowSegregated]
      [flow]
        compressibility = 'incompressible'

        density = 'rho'
        dynamic_viscosity = 'mu'

        initial_velocity = '1 1 0'
        initial_pressure = 0.0

        inlet_boundaries = 'left'
        momentum_inlet_types = 'fixed-velocity'
        momentum_inlet_function = '1 0'
        wall_boundaries = 'top bottom'
        momentum_wall_types = 'noslip noslip'
        outlet_boundaries = 'right'
        momentum_outlet_types = 'fixed-pressure'
        pressure_function = '0'

        friction_types = 'darcy'
        friction_coeffs = 'friction_coefficient'

        momentum_advection_interpolation = 'average'
      []
    []
  []
[]

[FunctorMaterials]
  [const]
    type = ADGenericFunctorMaterial
    prop_names = 'rho mu'
    prop_values = '${rho} ${mu}'
  []
  [friction_coefficient]
    type = ADGenericVectorFunctorMaterial
    prop_names = 'friction_coefficient'
    prop_values = '25 25 25'
  []
[]

[Problem]
  linear_sys_names = 'u_system v_system pressure_system'
[]

[Executioner]
  type = SIMPLE
  rhie_chow_user_object = 'ins_rhie_chow_interpolator'

  # Systems
  momentum_systems = 'u_system v_system'
  pressure_system = 'pressure_system'
  momentum_equation_relaxation = 0.8
  pressure_variable_relaxation = 0.3

  # We need to converge the problem to show conservation
  num_iterations = 200
  pressure_absolute_tolerance = 1e-10
  momentum_absolute_tolerance = 1e-10
  momentum_petsc_options_iname = '-pc_type -pc_hypre_type'
  momentum_petsc_options_value = 'hypre boomeramg'
  pressure_petsc_options_iname = '-pc_type -pc_hypre_type'
  pressure_petsc_options_value = 'hypre boomeramg'
  momentum_l_abs_tol = 1e-13
  pressure_l_abs_tol = 1e-13
  momentum_l_tol = 0
  pressure_l_tol = 0
  # print_fields = true
  continue_on_max_its = true
[]

[Outputs]
  exodus = true
  csv = true
[]

[Postprocessors]
  [dp]
    type = PressureDrop
    pressure = 'pressure'
    upstream_boundary = 'left'
    downstream_boundary = 'right'
    boundary = 'left right'
  []
[]

(modules/navier_stokes/test/tests/finite_volume/two_phase/mixture_model/segregated/channel-drift-flux.i)

mu = 1.0
rho = 10.0
mu_d = 0.1
rho_d = 1.0
l = 2
# 'average' leads to slight oscillations, upwind may be preferred
# This method is selected for consistency with the original nonlinear input
advected_interp_method = 'average'

# TODO remove need for those
cp = 1
k = 1
cp_d = 1
k_d = 1

[Mesh]
  [gen]
    type = GeneratedMeshGenerator
    dim = 2
    xmin = 0
    xmax = '${fparse l * 5}'
    ymin = '${fparse -l / 2}'
    ymax = '${fparse l / 2}'
    nx = 10
    ny = 4
  []
  uniform_refine = 0
[]

[Problem]
  linear_sys_names = 'u_system v_system pressure_system phi_system'
  previous_nl_solution_required = true
[]

[Variables]
  [vel_x]
    type = MooseLinearVariableFVReal
    solver_sys = u_system
    initial_condition = 1
  []
  [vel_y]
    type = MooseLinearVariableFVReal
    solver_sys = v_system
  []
  [pressure]
    type = MooseLinearVariableFVReal
    solver_sys = pressure_system
  []
  [phase_2]
    type = MooseLinearVariableFVReal
    solver_sys = phi_system
  []
[]

[LinearFVKernels]
  [flow_p_diffusion]
    type = LinearFVAnisotropicDiffusion
    diffusion_tensor = Ainv
    use_nonorthogonal_correction = false
    variable = pressure
  []
  [flow_HbyA_divergence]
    type = LinearFVDivergence
    face_flux = HbyA
    force_boundary_execution = true
    variable = pressure
  []
  [flow_ins_momentum_flux_x]
    type = LinearWCNSFVMomentumFlux
    advected_interp_method = ${advected_interp_method}
    momentum_component = x
    mu = mu_mixture
    rhie_chow_user_object = ins_rhie_chow_interpolator
    u = vel_x
    use_deviatoric_terms = false
    use_nonorthogonal_correction = false
    v = vel_y
    variable = vel_x
  []
  [flow_ins_momentum_flux_y]
    type = LinearWCNSFVMomentumFlux
    advected_interp_method = ${advected_interp_method}
    momentum_component = y
    mu = mu_mixture
    rhie_chow_user_object = ins_rhie_chow_interpolator
    u = vel_x
    use_deviatoric_terms = false
    use_nonorthogonal_correction = false
    v = vel_y
    variable = vel_y
  []
  [mixture_drift_flux_x]
    type = LinearWCNSFV2PMomentumDriftFlux
    density_interp_method = average
    fraction_dispersed = phase_2
    momentum_component = x
    rhie_chow_user_object = ins_rhie_chow_interpolator
    rho_d = ${rho_d}
    u_slip = vel_slip_x
    v_slip = vel_slip_y
    variable = vel_x
  []
  [mixture_drift_flux_y]
    type = LinearWCNSFV2PMomentumDriftFlux
    density_interp_method = average
    fraction_dispersed = phase_2
    momentum_component = y
    rhie_chow_user_object = ins_rhie_chow_interpolator
    rho_d = ${rho_d}
    u_slip = vel_slip_x
    v_slip = vel_slip_y
    variable = vel_y
  []
  [flow_ins_momentum_pressure_x]
    type = LinearFVMomentumPressure
    momentum_component = x
    pressure = pressure
    variable = vel_x
  []
  [flow_ins_momentum_pressure_y]
    type = LinearFVMomentumPressure
    momentum_component = y
    pressure = pressure
    variable = vel_y
  []
  [flow_momentum_friction_0_x]
    type = LinearFVMomentumFriction
    Darcy_name = Darcy_coefficient_vec
    momentum_component = x
    mu = mu_mixture
    variable = vel_x
  []
  [flow_momentum_friction_0_y]
    type = LinearFVMomentumFriction
    Darcy_name = Darcy_coefficient_vec
    momentum_component = y
    mu = mu_mixture
    variable = vel_y
  []

  # Mixture phase equation
  [mixture_ins_phase_2_advection]
    type = LinearFVScalarAdvection
    advected_interp_method = upwind
    rhie_chow_user_object = ins_rhie_chow_interpolator
    u_slip = vel_slip_x
    v_slip = vel_slip_y
    variable = phase_2
  []
  [mixture_phase_interface_reaction]
    type = LinearFVReaction
    coeff = 0.1
    variable = phase_2
  []
  [mixture_phase_interface_source]
    type = LinearFVSource
    scaling_factor = 0.1
    source_density = phase_1
    variable = phase_2
  []
[]

[LinearFVBCs]
  [vel_x_left]
    type = LinearFVAdvectionDiffusionFunctorDirichletBC
    boundary = left
    functor = 1
    variable = vel_x
  []
  [vel_y_left]
    type = LinearFVAdvectionDiffusionFunctorDirichletBC
    boundary = left
    functor = 0
    variable = vel_y
  []
  [pressure_extrapolation_inlet_left]
    type = LinearFVExtrapolatedPressureBC
    boundary = left
    use_two_term_expansion = true
    variable = pressure
  []
  [vel_x_right]
    type = LinearFVAdvectionDiffusionOutflowBC
    boundary = right
    use_two_term_expansion = true
    variable = vel_x
  []
  [vel_y_right]
    type = LinearFVAdvectionDiffusionOutflowBC
    boundary = right
    use_two_term_expansion = true
    variable = vel_y
  []
  [pressure_right]
    type = LinearFVAdvectionDiffusionFunctorDirichletBC
    boundary = right
    functor = 0
    variable = pressure
  []
  [vel_x_bottom]
    type = LinearFVAdvectionDiffusionFunctorDirichletBC
    boundary = bottom
    functor = 0
    variable = vel_x
  []
  [vel_y_bottom]
    type = LinearFVAdvectionDiffusionFunctorDirichletBC
    boundary = bottom
    functor = 0
    variable = vel_y
  []
  [vel_x_top]
    type = LinearFVAdvectionDiffusionFunctorDirichletBC
    boundary = top
    functor = 0
    variable = vel_x
  []
  [vel_y_top]
    type = LinearFVAdvectionDiffusionFunctorDirichletBC
    boundary = top
    functor = 0
    variable = vel_y
  []
  [pressure_extrapolation_top_bottom]
    type = LinearFVExtrapolatedPressureBC
    boundary = 'top bottom'
    use_two_term_expansion = true
    variable = pressure
  []

  [phase_2_left]
    type = LinearFVAdvectionDiffusionFunctorDirichletBC
    boundary = left
    functor = 0.1
    variable = phase_2
  []
  [phase_2_right]
    type = LinearFVAdvectionDiffusionOutflowBC
    boundary = right
    use_two_term_expansion = true
    variable = phase_2
  []
[]

[FunctorMaterials]
  [flow_ins_speed_material]
    type = ADVectorMagnitudeFunctorMaterial
    execute_on = ALWAYS
    outputs = none
    vector_magnitude_name = speed
    x_functor = vel_x
    y_functor = vel_y
  []

  [mixture_phase_1_fraction]
    type = ParsedFunctorMaterial
    execute_on = ALWAYS
    expression = '1 - phase_2'
    functor_names = phase_2
    output_properties = phase_1
    outputs = all
    property_name = phase_1
  []
  [mixture_mixture_material]
    type = WCNSLinearFVMixtureFunctorMaterial
    execute_on = ALWAYS
    limit_phase_fraction = true
    outputs = all
    phase_1_fraction = phase_2
    phase_1_names = '${rho_d} ${mu_d} ${cp_d} ${k_d}'
    phase_2_names = '${rho}   ${mu}   ${cp}   ${k}'
    prop_names = 'rho_mixture mu_mixture cp_mixture k_mixture'
  []
  [mixture_slip_x]
    type = WCNSFV2PSlipVelocityFunctorMaterial
    execute_on = ALWAYS
    gravity = '0 0 0'
    linear_coef_name = Darcy_coefficient
    momentum_component = x
    mu = mu_mixture
    outputs = all
    particle_diameter = 0.01
    rho = ${rho}
    rho_d = ${rho_d}
    slip_velocity_name = vel_slip_x
    u = vel_x
    v = vel_y
  []
  [mixture_slip_y]
    type = WCNSFV2PSlipVelocityFunctorMaterial
    execute_on = ALWAYS
    gravity = '0 0 0'
    linear_coef_name = Darcy_coefficient
    momentum_component = y
    mu = mu_mixture
    outputs = all
    particle_diameter = 0.01
    rho = ${rho}
    rho_d = ${rho_d}
    slip_velocity_name = vel_slip_y
    u = vel_x
    v = vel_y
  []
  [mixture_dispersed_drag]
    type = NSFVDispersePhaseDragFunctorMaterial
    drag_coef_name = Darcy_coefficient
    execute_on = ALWAYS
    mu = mu_mixture
    outputs = all
    particle_diameter = 0.01
    rho = rho_mixture
    u = vel_x
    v = vel_y
  []
[]

[UserObjects]
  [ins_rhie_chow_interpolator]
    type = RhieChowMassFlux
    p_diffusion_kernel = flow_p_diffusion
    pressure = pressure
    rho = rho_mixture
    u = vel_x
    v = vel_y
  []
[]

[Executioner]
  type = SIMPLE
  rhie_chow_user_object = 'ins_rhie_chow_interpolator'

  # Systems
  momentum_systems = 'u_system v_system'
  pressure_system = 'pressure_system'
  active_scalar_systems = 'phi_system'
  momentum_equation_relaxation = 0.8
  active_scalar_equation_relaxation = '0.7'
  pressure_variable_relaxation = 0.3

  # We need to converge the problem to show conservation
  num_iterations = 200
  pressure_absolute_tolerance = 1e-10
  momentum_absolute_tolerance = 1e-10
  active_scalar_absolute_tolerance = '1e-10'
  momentum_petsc_options_iname = '-pc_type -pc_hypre_type'
  momentum_petsc_options_value = 'hypre boomeramg'
  pressure_petsc_options_iname = '-pc_type -pc_hypre_type'
  pressure_petsc_options_value = 'hypre boomeramg'
  active_scalar_petsc_options_iname = '-pc_type -pc_hypre_type'
  active_scalar_petsc_options_value = 'hypre boomeramg'
  momentum_l_abs_tol = 1e-13
  pressure_l_abs_tol = 1e-13
  active_scalar_l_abs_tol = 1e-13
  momentum_l_tol = 0
  pressure_l_tol = 0
  active_scalar_l_tol = 0
  # print_fields = true
  continue_on_max_its = true
[]

[Outputs]
  csv = true
[]

[Postprocessors]
  [Re]
    type = ParsedPostprocessor
    expression = '10.0 * 2 * 1'
  []
  [average_phase2]
    type = ElementAverageValue
    variable = phase_2
  []
  [dp]
    type = PressureDrop
    boundary = 'left right'
    downstream_boundary = right
    pressure = pressure
    upstream_boundary = left
  []
  [max_phase2]
    type = ElementExtremeValue
    variable = phase_2
  []
[]

(modules/navier_stokes/test/tests/finite_volume/two_phase/mixture_model/segregated/channel-drift-flux-physics.i)

mu = 1.0
rho = 10.0
mu_d = 0.1
rho_d = 1.0
l = 2
U = 1
dp = 0.01
inlet_phase_2 = 0.1
# 'average' leads to slight oscillations, upwind may be preferred
advected_interp_method = 'average'

# TODO remove need for those
cp = 1
k = 1
cp_d = 1
k_d = 1

[Mesh]
  [gen]
    type = GeneratedMeshGenerator
    dim = 2
    xmin = 0
    xmax = '${fparse l * 5}'
    ymin = '${fparse -l / 2}'
    ymax = '${fparse l / 2}'
    nx = 10
    ny = 4
  []
  uniform_refine = 0
[]

[Problem]
  linear_sys_names = 'u_system v_system pressure_system phi_system'
[]

[Physics]
  [NavierStokes]
    [FlowSegregated]
      [flow]
        compressibility = 'incompressible'

        density = 'rho_mixture'
        dynamic_viscosity = 'mu_mixture'

        # Initial conditions
        initial_velocity = '${U} 0 0'
        initial_pressure = 0

        # Boundary conditions
        inlet_boundaries = 'left'
        momentum_inlet_types = 'fixed-velocity'
        momentum_inlet_functors = '${U} 0'

        wall_boundaries = 'top bottom'
        momentum_wall_types = 'noslip noslip'

        outlet_boundaries = 'right'
        momentum_outlet_types = 'fixed-pressure'
        pressure_functors = '0'

        # Friction is done in drift flux term
        friction_types = "Darcy"
        friction_coeffs = "Darcy_coefficient_vec"
        standard_friction_formulation = true

        momentum_advection_interpolation = '${advected_interp_method}'
        orthogonality_correction = false

        # To match reference better
        pressure_two_term_bc_expansion = true
        momentum_two_term_bc_expansion = true
      []
    []
    [TwoPhaseMixtureSegregated]
      [mixture]
        system_names = 'phi_system'
        phase_1_fraction_name = 'phase_1'
        phase_2_fraction_name = 'phase_2'

        # Phase transport equation
        add_phase_transport_equation = true
        alpha_exchange = 0.1
        phase_advection_interpolation = 'upwind'

        # see flow for inlet boundaries
        phase_fraction_inlet_type = 'fixed-value'
        phase_fraction_inlet_functors = '${inlet_phase_2}'

        # Drift flux parameters
        add_drift_flux_momentum_terms = true
        density_interp_method = 'average'
        # This has to be consistent with the friction model
        slip_linear_friction_name = 'Darcy_coefficient'

        # Base phase material properties
        phase_1_density_name = ${rho}
        phase_1_viscosity_name = ${mu}
        phase_1_specific_heat_name = ${cp}
        phase_1_thermal_conductivity_name = ${k}

        # Other phase material properties
        phase_2_density_name = ${rho_d}
        phase_2_viscosity_name = ${mu_d}
        phase_2_specific_heat_name = ${cp_d}
        phase_2_thermal_conductivity_name = ${k_d}
        output_all_properties = true

        # Friction model
        use_dispersed_phase_drag_model = true
        particle_diameter = ${dp}
        add_advection_slip_term = false
      []
    []
  []
[]

[Executioner]
  type = SIMPLE
  rhie_chow_user_object = 'ins_rhie_chow_interpolator'

  # Systems
  momentum_systems = 'u_system v_system'
  pressure_system = 'pressure_system'
  active_scalar_systems = 'phi_system'
  momentum_equation_relaxation = 0.8
  active_scalar_equation_relaxation = '0.7'
  pressure_variable_relaxation = 0.3

  # We need to converge the problem to show conservation
  num_iterations = 200
  pressure_absolute_tolerance = 1e-10
  momentum_absolute_tolerance = 1e-10
  active_scalar_absolute_tolerance = '1e-10'
  momentum_petsc_options_iname = '-pc_type -pc_hypre_type'
  momentum_petsc_options_value = 'hypre boomeramg'
  pressure_petsc_options_iname = '-pc_type -pc_hypre_type'
  pressure_petsc_options_value = 'hypre boomeramg'
  active_scalar_petsc_options_iname = '-pc_type -pc_hypre_type'
  active_scalar_petsc_options_value = 'hypre boomeramg'
  momentum_l_abs_tol = 1e-13
  pressure_l_abs_tol = 1e-13
  active_scalar_l_abs_tol = 1e-13
  momentum_l_tol = 0
  pressure_l_tol = 0
  active_scalar_l_tol = 0
  # print_fields = true
  continue_on_max_its = true
[]

[Outputs]
  print_linear_residuals = true
  print_nonlinear_residuals = true
  csv = true
  [out]
    type = Exodus
    hide = 'Re dp'
  []
  execute_on = 'INITIAL TIMESTEP_END'
[]

[Postprocessors]
  [Re]
    type = ParsedPostprocessor
    expression = '${rho} * ${l} * ${U}'
  []
  [dp]
    type = PressureDrop
    pressure = 'pressure'
    upstream_boundary = 'left'
    downstream_boundary = 'right'
    boundary = 'left right'
  []
  [average_phase2]
    type = ElementAverageValue
    variable = 'phase_2'
  []
  [max_phase2]
    type = ElementExtremeValue
    variable = 'phase_2'
  []
[]

(modules/navier_stokes/test/tests/finite_volume/materials/flow_diode/transient_operation.i)

# Horizontal H junction with flow in different directions in the two branches
# One of the branches has a diode against the direction of the flow that can
# be triggered using the Controls
# There are 3 different strategies available for the diode blocking the flow
# - based on a time trigger
# - based on a pressure drop (here chosen across the diode)
# - based on a mass flow rate (here chosen through the diode)

mu = 0.1
rho = 10

nx = 10
ny = 5

[Mesh]
  [cmg]
    type = CartesianMeshGenerator
    dim = 2
    dx = '1 0.3 1'
    dy = '0.5 0.2 0.5'
    ix = '${nx} ${fparse nx/2} ${nx}'
    iy = '${ny} ${ny} ${ny}'
    subdomain_id = '1 1 1
                    2 1 2
                    3 4 1'
  []

  [add_walls]
    type = SideSetsBetweenSubdomainsGenerator
    input = 'cmg'
    primary_block = '1 3 4'
    paired_block = '2'
    new_boundary = 'walls'
  []
  [remove_wall_blocks]
    type = BlockDeletionGenerator
    input = add_walls
    block = 2
  []

  # Add inlets and outlets
  [top_left]
    type = ParsedGenerateSideset
    input = remove_wall_blocks
    combinatorial_geometry = 'x<0.001 & y>0.6'
    new_sideset_name = top_left
  []
  [bottom_left]
    type = ParsedGenerateSideset
    input = top_left
    combinatorial_geometry = 'x<0.001 & y<0.6'
    new_sideset_name = bottom_left
  []
  [top_right]
    type = ParsedGenerateSideset
    input = bottom_left
    combinatorial_geometry = 'x>2.299 & y>0.6'
    new_sideset_name = top_right
  []
  [bottom_right]
    type = ParsedGenerateSideset
    input = top_right
    combinatorial_geometry = 'x>2.299 & y<0.6'
    new_sideset_name = bottom_right
  []

  # Extra surfaces
  [diode_inlet]
    type = SideSetsBetweenSubdomainsGenerator
    input = bottom_right
    primary_block = 4
    paired_block = 3
    new_boundary = 'diode_inlet'
  []
  [mid_section]
    type = SideSetsBetweenSubdomainsGenerator
    input = diode_inlet
    primary_block = 4
    paired_block = 1
    new_boundary = 'mid_connection'
  []

  [reduce_blocks]
    type = RenameBlockGenerator
    input = 'mid_section'
    old_block = '4 3 1'
    new_block = '1 diode fluid'
  []
[]

[GlobalParams]
  rhie_chow_user_object = 'pins_rhie_chow_interpolator'
  advected_interp_method = 'upwind'
  velocity_interp_method = 'rc'
[]

[Modules]
  [NavierStokesFV]
    compressibility = 'incompressible'
    porous_medium_treatment = true

    density = ${rho}
    dynamic_viscosity = ${mu}

    initial_velocity = '1e-6 1e-6 0'
    initial_pressure = 0.0

    inlet_boundaries = 'bottom_left top_right'
    momentum_inlet_types = 'fixed-velocity fixed-velocity'
    momentum_inlet_function = '1 0; -1 0'

    wall_boundaries = 'top bottom walls'
    momentum_wall_types = 'noslip noslip noslip'

    outlet_boundaries = 'bottom_right top_left'
    momentum_outlet_types = 'fixed-pressure fixed-pressure'
    pressure_function = '1 1'

    friction_blocks = 'fluid; diode'
    friction_types = 'darcy forchheimer; darcy forchheimer'
    standard_friction_formulation = true
    # Base friction
    # friction_coeffs = 'Darcy Forchheimer; Darcy Forchheimer'
    # Combined with diode
    friction_coeffs = 'combined_linear combined_quadratic; combined_linear combined_quadratic'

    # Porosity jump treatment
    # Option 1: diffusion correction
    use_friction_correction = true
    consistent_scaling = 10

    # Option 2: bernouilli jump
    # porosity_interface_pressure_treatment = bernoulli

    mass_advection_interpolation = 'average'
    momentum_advection_interpolation = 'average'
  []
[]

[FunctorMaterials]
  [porosity]
    type = ADGenericFunctorMaterial
    prop_names = 'porosity'
    prop_values = '0.5'
  []
  [base_friction]
    type = ADGenericVectorFunctorMaterial
    prop_names = 'Darcy Forchheimer'
    prop_values = '220 240 260 0 0 0'
  []

  # Material definitions needed for the diode
  [diode]
    type = NSFVFrictionFlowDiodeFunctorMaterial
    # Friction only in X direction
    direction = '-1 0 0'
    additional_linear_resistance = '20000 0 0'
    additional_quadratic_resistance = '0 0 0'
    base_linear_friction_coefs = 'Darcy'
    base_quadratic_friction_coefs = 'Forchheimer'
    sum_linear_friction_name = 'diode_linear'
    sum_quadratic_friction_name = 'diode_quad'
    block = 'diode'
    turn_on_diode = false
  []
  [combine_linear_friction]
    type = ADPiecewiseByBlockVectorFunctorMaterial
    prop_name = 'combined_linear'
    subdomain_to_prop_value = 'fluid Darcy
                               diode diode_linear'
  []
  [combine_quadratic_friction]
    type = ADPiecewiseByBlockVectorFunctorMaterial
    prop_name = 'combined_quadratic'
    subdomain_to_prop_value = 'fluid Forchheimer
                               diode diode_quad'
  []

  # density is constant
  [momentum]
    type = ADGenericVectorFunctorMaterial
    prop_names = 'momentum'
    prop_values = 'superficial_vel_x superficial_vel_y 0'
  []
[]

[Executioner]
  type = Transient
  solve_type = NEWTON
  petsc_options_iname = '-pc_type -pc_factor_shift_type -ksp_gmres_restart'
  petsc_options_value = 'lu       NONZERO               200'
  line_search = 'none'

  end_time = 0.2
  dt = 0.015
  nl_abs_tol = 1e-12
[]

[Controls]
  active = 'pdrop_based'
  # Case 1: Diode turns on at a certain time and blocks (adds friction) flow at a given time
  [time_based]
    type = BoolFunctionControl
    function = time_function
    parameter = 'FunctorMaterials/diode/turn_on_diode'
    execute_on = timestep_begin
  []

  # Case 2: Diode looks at pressure drop, reduces flow if positive pressure drop
  # This will not oscillate as the diode increases the pressure drop
  [pdrop_based]
    type = BoolFunctionControl
    function = pdrop_positive
    parameter = 'FunctorMaterials/diode/turn_on_diode'
    execute_on = timestep_begin
  []

  # Case 3: Diode looks at flow direction & quantity, reduces flow if too much flow
  # in a given direction
  # This will oscillate (turn on/off on each step) if the action of turning the diode
  # makes the amount of flow smaller than the threshold for turning on the diode
  [flow_based]
    type = BoolFunctionControl
    function = velocity_big_enough
    parameter = 'FunctorMaterials/diode/turn_on_diode'
    execute_on = timestep_begin
  []
[]

[Functions]
  # Functions are used to parse postprocessors and provide them to a BoolFunctionControl
  [time_function]
    type = ParsedFunction
    expression = 'if(t<0.1, 0, 1)'
  []
  [pdrop_positive]
    type = ParsedFunction
    expression = 'if(pdrop_diode>100, 1, 0)'
    symbol_names = pdrop_diode
    symbol_values = pdrop_diode
  []
  [velocity_big_enough]
    type = ParsedFunction
    expression = 'if(flow_diode<-0.4, 1, 0)'
    symbol_names = flow_diode
    symbol_values = flow_diode
  []
[]

[Postprocessors]
  # Analysis of the simulation
  [mdot_top]
    type = VolumetricFlowRate
    boundary = 'top_right'
    vel_x = superficial_vel_x
    vel_y = superficial_vel_y
    advected_quantity = ${rho}
  []
  [mdot_bottom]
    type = VolumetricFlowRate
    boundary = 'bottom_right'
    vel_x = superficial_vel_x
    vel_y = superficial_vel_y
    advected_quantity = ${rho}
  []
  [mdot_middle]
    type = VolumetricFlowRate
    boundary = 'mid_connection'
    vel_x = superficial_vel_x
    vel_y = superficial_vel_y
    advected_quantity = ${rho}
  []
  [pdrop_top_channel]
    type = PressureDrop
    upstream_boundary = 'top_left'
    downstream_boundary = 'top_right'
    weighting_functor = 'momentum'
    boundary = 'top_left top_right'
    pressure = pressure
  []
  [pdrop_bottom_channel]
    type = PressureDrop
    upstream_boundary = 'bottom_left'
    downstream_boundary = 'bottom_right'
    weighting_functor = 'momentum'
    boundary = 'bottom_left bottom_right'
    pressure = pressure
  []

  # Diode operation
  [pdrop_diode]
    type = PressureDrop
    upstream_boundary = 'diode_inlet'
    downstream_boundary = 'top_left'
    weighting_functor = 'momentum'
    boundary = 'diode_inlet top_left'
    pressure = pressure
  []
  [flow_diode]
    type = VolumetricFlowRate
    boundary = 'diode_inlet'
    vel_x = superficial_vel_x
    vel_y = superficial_vel_y
    advected_quantity = ${rho}
  []
[]

[Outputs]
  exodus = true
  csv = true
[]

(modules/navier_stokes/test/tests/postprocessors/pressure_drop/drop_insad.i)

[Mesh]
  second_order = true
  inactive = 'mesh internal_boundary_bot internal_boundary_top'
  [mesh]
    type = CartesianMeshGenerator
    dim = 2
    dx = '1'
    dy = '1 1 1'
    ix = '5'
    iy = '5 5 5'
    subdomain_id = '1
                    2
                    3'
  []
  [internal_boundary_bot]
    type = SideSetsBetweenSubdomainsGenerator
    input = mesh
    new_boundary = 'internal_bot'
    primary_block = 1
    paired_block = 2
  []
  [internal_boundary_top]
    type = SideSetsBetweenSubdomainsGenerator
    input = internal_boundary_bot
    new_boundary = 'internal_top'
    primary_block = 2
    paired_block = 3
  []
  [diverging_mesh]
    type = FileMeshGenerator
    file = 'expansion_quad.e'
  []
[]

[Modules]
  [IncompressibleNavierStokes]
    equation_type = steady-state

    # no slip BCs
    velocity_boundary = 'bottom right left'
    velocity_function = '0 1    0 0   0 0'
    pressure_boundary = 'top'
    pressure_function = '1'

    density_name = rho
    dynamic_viscosity_name = mu

    integrate_p_by_parts = false
    order = SECOND
  []
[]

[Materials]
  [const]
    type = GenericConstantMaterial
    block = '1 2 3'
    prop_names = 'rho mu'
    prop_values = '1  1'
  []
[]

[FunctorMaterials]
  [ADconst]
    type = ADGenericFunctorMaterial
    block = '1 2 3'
    prop_names = 'rho_ad'
    prop_values = '1'
  []
  [vel_functor]
    type = ADGenericVectorFunctorMaterial
    prop_names = 'velocity'
    prop_values = 'vel_x vel_y 0'
  []
[]

[Preconditioning]
  [SMP_PJFNK]
    type = SMP
    full = true
  []
[]

[Executioner]
  type = Steady
  solve_type = PJFNK
  petsc_options_iname = '-ksp_gmres_restart -pc_type -sub_pc_type -sub_pc_factor_levels'
  petsc_options_value = '300                bjacobi  ilu          4'
  line_search = none
  nl_rel_tol = 1e-12
  nl_max_its = 6
  l_tol = 1e-6
  l_max_its = 300
[]

[Postprocessors]
  [pdrop_total]
    type = PressureDrop
    pressure = p
    upstream_boundary = 'bottom'
    downstream_boundary = 'top'
    boundary = 'top bottom'
  []
  [pdrop_mid1]
    type = PressureDrop
    pressure = p
    upstream_boundary = 'bottom'
    downstream_boundary = 'internal_bot'
    boundary = 'bottom internal_bot'
  []
  [pdrop_mid2]
    type = PressureDrop
    pressure = p
    upstream_boundary = 'internal_bot'
    downstream_boundary = 'internal_top'
    boundary = 'internal_top internal_bot'
  []
  [pdrop_mid3]
    type = PressureDrop
    pressure = p
    upstream_boundary = 'internal_top'
    downstream_boundary = 'top'
    boundary = 'top internal_top'
  []
  [sum_drops]
    type = ParsedPostprocessor
    expression = 'pdrop_mid1 + pdrop_mid2 + pdrop_mid3'
    pp_names = 'pdrop_mid1 pdrop_mid2 pdrop_mid3'
  []

  [p_upstream]
    type = SideAverageValue
    variable = p
    boundary = 'bottom'
  []
  [p_downstream]
    type = SideAverageValue
    variable = p
    boundary = 'top'
  []
[]

[Outputs]
  exodus = false
  csv = true
[]

(modules/navier_stokes/test/tests/finite_volume/ins/channel-flow/friction/2d-rc-friction-standard-nonlinear-physics.i)

mu = 1.1
rho = 1.1

[Mesh]
  [gen]
    type = GeneratedMeshGenerator
    dim = 2
    xmin = 0
    xmax = 5
    ymin = -1
    ymax = 1
    nx = 50
    ny = 10
  []
[]

[Physics]
  [NavierStokes]
    [Flow]
      [flow]
        compressibility = 'incompressible'

        density = 'rho'
        dynamic_viscosity = 'mu'

        initial_velocity = '1 0 0'
        initial_pressure = 0.0

        inlet_boundaries = 'left'
        momentum_inlet_types = 'fixed-velocity'
        momentum_inlet_function = '1 0'
        wall_boundaries = 'top bottom'
        momentum_wall_types = 'noslip noslip'
        outlet_boundaries = 'right'
        momentum_outlet_types = 'fixed-pressure'
        pressure_function = '0'

        friction_types = 'darcy'
        friction_coeffs = 'friction_coefficient'

        mass_advection_interpolation = 'average'
        momentum_advection_interpolation = 'average'
        standard_friction_formulation = true
      []
    []
  []
[]

[FunctorMaterials]
  [const]
    type = ADGenericFunctorMaterial
    prop_names = 'rho mu'
    prop_values = '${rho} ${mu}'
  []
  [friction_coefficient]
    type = ADGenericVectorFunctorMaterial
    prop_names = 'friction_coefficient'
    prop_values = '25 25 25'
  []
[]

[Executioner]
  type = Steady
  solve_type = 'NEWTON'
  petsc_options_iname = '-pc_type -pc_factor_shift_type'
  petsc_options_value = 'lu NONZERO'
  nl_rel_tol = 1e-12
[]

[Outputs]
  exodus = true
  csv = true
[]

[Postprocessors]
  [dp]
    type = PressureDrop
    pressure = 'pressure'
    upstream_boundary = 'left'
    downstream_boundary = 'right'
    boundary = 'left right'
  []
[]

(modules/navier_stokes/test/tests/postprocessors/pressure_drop/drop_insfv.i)

mu=1
rho=1
advected_interp_method='average'
velocity_interp_method='rc'

[GlobalParams]
  rhie_chow_user_object = 'rc'
  advected_interp_method = ${advected_interp_method}
  velocity_interp_method = ${velocity_interp_method}
[]

[UserObjects]
  [rc]
    type = INSFVRhieChowInterpolator
    u = u
    v = v
    pressure = pressure
  []
[]

[Mesh]
  inactive = 'mesh internal_boundary_bot internal_boundary_top'
  [mesh]
    type = CartesianMeshGenerator
    dim = 2
    dx = '1'
    dy = '1 1 1'
    ix = '5'
    iy = '5 5 5'
    subdomain_id = '1
                    2
                    3'
  []
  [internal_boundary_bot]
    type = SideSetsBetweenSubdomainsGenerator
    input = mesh
    new_boundary = 'internal_bot'
    primary_block = 1
    paired_block = 2
  []
  [internal_boundary_top]
    type = SideSetsBetweenSubdomainsGenerator
    input = internal_boundary_bot
    new_boundary = 'internal_top'
    primary_block = 2
    paired_block = 3
  []
  [diverging_mesh]
    type = FileMeshGenerator
    file = 'expansion_quad.e'
  []
[]

[Variables]
  [u]
    type = INSFVVelocityVariable
    initial_condition = 0
  []
  [v]
    type = INSFVVelocityVariable
    initial_condition = 1
  []
  [pressure]
    type = INSFVPressureVariable
  []
  [temperature]
    type = INSFVEnergyVariable
  []
[]

[AuxVariables]
  [advected_density]
    type = MooseVariableFVReal
    initial_condition = ${rho}
  []
[]

[FVKernels]
  [mass]
    type = INSFVMassAdvection
    variable = pressure
    rho = ${rho}
  []

  [u_advection]
    type = INSFVMomentumAdvection
    variable = u
    rho = ${rho}
    momentum_component = 'x'
  []
  [u_viscosity]
    type = INSFVMomentumDiffusion
    variable = u
    mu = ${mu}
    force_boundary_execution = true
    momentum_component = 'x'
  []
  [u_pressure]
    type = INSFVMomentumPressure
    variable = u
    momentum_component = 'x'
    pressure = pressure
  []

  [v_advection]
    type = INSFVMomentumAdvection
    variable = v
    rho = ${rho}
    momentum_component = 'y'
  []
  [v_viscosity]
    type = INSFVMomentumDiffusion
    variable = v
    mu = ${mu}
    force_boundary_execution = true
    momentum_component = 'y'
  []
  [v_pressure]
    type = INSFVMomentumPressure
    variable = v
    momentum_component = 'y'
    pressure = pressure
  []

  [temp_advection]
    type = INSFVEnergyAdvection
    variable = temperature
    advected_interp_method = 'upwind'
  []
  [temp_source]
    type = FVBodyForce
    variable = temperature
    function = 10
    block = 1
  []
[]

[FVBCs]
  [inlet-u]
    type = INSFVInletVelocityBC
    boundary = 'bottom'
    variable = u
    function = 0
  []
  [inlet-v]
    type = INSFVInletVelocityBC
    boundary = 'bottom'
    variable = v
    function = 1
  []
  [noslip-u]
    type = INSFVNoSlipWallBC
    boundary = 'right'
    variable = u
    function = 0
  []
  [noslip-v]
    type = INSFVNoSlipWallBC
    boundary = 'right'
    variable = v
    function = 0
  []
  [axis-u]
    type = INSFVSymmetryVelocityBC
    boundary = 'left'
    variable = u
    u = u
    v = v
    mu = ${mu}
    momentum_component = x
  []
  [axis-v]
    type = INSFVSymmetryVelocityBC
    boundary = 'left'
    variable = v
    u = u
    v = v
    mu = ${mu}
    momentum_component = y
  []
  [axis-p]
    type = INSFVSymmetryPressureBC
    boundary = 'left'
    variable = pressure
  []
  [outlet_p]
    type = INSFVOutletPressureBC
    boundary = 'top'
    variable = pressure
    function = 0
  []
  [inlet_temp]
    type = FVNeumannBC
    boundary = 'bottom'
    variable = temperature
    value = 300
  []
[]

[FunctorMaterials]
  [ins_fv]
    type = INSFVEnthalpyFunctorMaterial
    temperature = 'temperature'
    rho = ${rho}
  []
  [advected_material_property]
    type = ADGenericFunctorMaterial
    prop_names = 'advected_rho cp'
    prop_values ='${rho} 1'
  []
  [vel_functor]
    type = ADGenericVectorFunctorMaterial
    prop_names = 'velocity'
    prop_values = 'u v 0'
  []
[]

[Executioner]
  type = Steady
  solve_type = 'NEWTON'
  petsc_options_iname = '-pc_type -ksp_gmres_restart -sub_pc_type -sub_pc_factor_shift_type'
  petsc_options_value = 'asm      200                lu           NONZERO'
  line_search = 'none'
  nl_rel_tol = 1e-12
[]

[Postprocessors]
  [pdrop_total]
    type = PressureDrop
    pressure = pressure
    upstream_boundary = 'bottom'
    downstream_boundary = 'top'
    boundary = 'top bottom'
  []
  [pdrop_mid1]
    type = PressureDrop
    pressure = pressure
    upstream_boundary = 'bottom'
    downstream_boundary = 'internal_bot'
    boundary = 'bottom internal_bot'
  []
  [pdrop_mid2]
    type = PressureDrop
    pressure = pressure
    upstream_boundary = 'internal_bot'
    downstream_boundary = 'internal_top'
    boundary = 'internal_top internal_bot'
  []
  [pdrop_mid3]
    type = PressureDrop
    pressure = pressure
    upstream_boundary = 'internal_top'
    downstream_boundary = 'top'
    boundary = 'top internal_top'
  []
  [sum_drops]
    type = ParsedPostprocessor
    expression = 'pdrop_mid1 + pdrop_mid2 + pdrop_mid3'
    pp_names = 'pdrop_mid1 pdrop_mid2 pdrop_mid3'
  []

  [p_upstream]
    type = SideAverageValue
    variable = pressure
    boundary = 'bottom'
  []
  [p_downstream]
    type = SideAverageValue
    variable = pressure
    boundary = 'top'
  []
[]

[Outputs]
  csv = true
[]

Using a weighting functor on local pressures
Example input syntax
Input Parameters
Input Files