NearestNodeNumberUO

This UserObject computes the closest node to a given point. (If there is a tie, then the node with the smallest ID is used.) It is used by the GeochemistryConsoleOutput object to identify the node at which output is required.

note

You will probably want to set execute_on to initial to avoid unnecessary computations, unless you have adaptive meshing, in which case set execute_on to initial and timestep_begin.

Input Parameters

pointThe point
C++ Type:libMesh::Point
Controllable:No
Description:The point

Required Parameters

blockThe list of blocks (ids or names) that this object will be applied
C++ Type:std::vector<SubdomainName>
Controllable:No
Description:The list of blocks (ids or names) that this object will be applied
boundaryThe list of boundaries (ids or names) from the mesh where this object applies
C++ Type:std::vector<BoundaryName>
Controllable:No
Description:The list of boundaries (ids or names) from the mesh where this object applies
unique_node_executeFalseWhen false (default), block restricted objects will have the execute method called multiple times on a single node if the node lies on a interface between two subdomains.
Default:False
C++ Type:bool
Controllable:No
Description:When false (default), block restricted objects will have the execute method called multiple times on a single node if the node lies on a interface between two subdomains.

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.
seed0The seed for the master random number generator
Default:0
C++ Type:unsigned int
Controllable:No
Description:The seed for the master random number generator
use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.
Default:False
C++ Type:bool
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

Input Files

(test/tests/postprocessors/nearest_node_number/nearest_node_number_2.i)
(modules/geochemistry/test/tests/geochemistry_console_output/console.i)
(modules/geochemistry/test/tests/equilibrium_models/HCl_no_action.i)
(test/tests/outputs/debug/show_execution_userobjects.i)
(test/tests/postprocessors/nearest_node_number/nearest_node_number_3.i)
(modules/geochemistry/test/tests/time_dependent_reactions/simple_no_action.i)
(test/tests/postprocessors/nearest_node_number/nearest_node_number_1.i)

(test/tests/postprocessors/nearest_node_number/nearest_node_number_2.i)

# Using NearestNodeNumber, finds the node number of the nearest node to the point in the mesh
# In this case, the mesh has two disjoint parts and the point is equidistant from the two parts, so the closest node with the smallest ID is chosen.
# This input file is run multiple times:
#  - 1 thread and 1 process
#  - 2 threads and 1 process
#  - 1 thread and 2 processes
#  - 2 threads and 2 processes
# Each time should give the same result
[Mesh]
  [left]
    type = GeneratedMeshGenerator
    dim = 1
    nx = 4
    xmin = 0
    xmax = 8
  []
  [right]
    type = GeneratedMeshGenerator
    dim = 1
    nx = 4
    xmin = 12
    xmax = 20
  []
  [combiner]
    type = CombinerGenerator
    inputs = 'left right'
  []

  # For consistency with distributed mesh
  allow_renumbering = false
[]

[UserObjects]
  [nnn_uo]
    type = NearestNodeNumberUO
    point = '10 0 0'
    execute_on = 'initial timestep_begin'
  []
[]
[Postprocessors]
  [nnn]
    type = NearestNodeNumber
    nearest_node_number_uo = nnn_uo
    execute_on = 'initial timestep_begin'
  []
[]

[Problem]
  solve = false
[]

[Executioner]
  type = Transient
  end_time = 2
[]

[Outputs]
  csv = true
[]

(modules/geochemistry/test/tests/geochemistry_console_output/console.i)

# An example of manually adding a GeochemistryConsoleOutput
[TimeDependentReactionSolver]
  model_definition = definition
  geochemistry_reactor_name = reactor_name
  charge_balance_species = "Cl-"
  constraint_species = "H2O H+ Cl- Fe+++"
  constraint_value = "  1.0 1.0E-2 1.3E-2 1.0E-3"
  constraint_meaning = "kg_solvent_water bulk_composition bulk_composition bulk_composition"
  constraint_unit = "kg moles moles moles"
  ramp_max_ionic_strength_initial = 0
  ramp_max_ionic_strength_subsequent = 1 # so can see the solver_info in the GeochemistryConsoleOutput
  kinetic_species_name = "Fe(OH)3(ppd)_nosorb"
  kinetic_species_initial_value = "1.0E-6"
  kinetic_species_unit = moles
  execute_console_output_on = 'final' # can compare with the specially_added one, below
[]

[UserObjects]
  [definition]
    type = GeochemicalModelDefinition
    database_file = "../../database/ferric_hydroxide_sorption.json"
    basis_species = "H2O H+ Cl- Fe+++"
    kinetic_minerals = "Fe(OH)3(ppd)_nosorb"
  []
  [nearest_node]
    type = NearestNodeNumberUO
    point = '0 0 0' # in this case there is no spatial dependence, so the point is rather irrelevant
  []
[]

[Executioner]
  type = Steady
[]

[Outputs]
  [specially_added]
    type = GeochemistryConsoleOutput
    geochemistry_reactor = reactor_name
    precision = 8 # 8 digits of precision
    mol_cutoff = 1E-8 # species with molality or mole-number lower than this are not outputted
    solver_info = true
    nearest_node_number_UO = nearest_node
    execute_on = 'final' # just output at the end of the simulation
  []
[]

(modules/geochemistry/test/tests/equilibrium_models/HCl_no_action.i)

# This is an example of an input file that does not utilize an action.  Its functionality is the same as HCl.i
# This solves for molalities in a system just containing HCl
[GlobalParams]
  point = '0 0 0'
[]

[Mesh]
  type = GeneratedMesh
  dim = 1
  nx= 1
[]

[Variables]
  [u]
  []
[]

[Kernels]
  [u]
    type = Diffusion
    variable = u
  []
[]

[AuxVariables]
  [solution_temperature]
  []
  [kg_solvent_H2O]
  []
  [activity_H2O]
  []
  [bulk_moles_H2O]
  []
  [pH]
  []
  [molal_H+]
  []
  [molal_Cl-]
  []
  [molal_HCl]
  []
  [molal_OH-]
  []
  [mg_per_kg_H+]
  []
  [mg_per_kg_Cl-]
  []
  [mg_per_kg_HCl]
  []
  [mg_per_kg_OH-]
  []
  [activity_H+]
  []
  [activity_Cl-]
  []
  [activity_HCl]
  []
  [activity_OH-]
  []
  [bulk_moles_H+]
  []
  [bulk_moles_Cl-]
  []
  [bulk_moles_HCl]
  []
  [bulk_moles_OH-]
  []
[]

[AuxKernels]
  [solution_temperature]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = solution_temperature
    quantity = temperature
  []
  [kg_solvent_H2O]
    type = GeochemistryQuantityAux
    species = 'H2O'
    reactor = reactor
    variable = kg_solvent_H2O
    quantity = molal
  []
  [activity_H2O]
    type = GeochemistryQuantityAux
    species = 'H2O'
    reactor = reactor
    variable = activity_H2O
    quantity = activity
  []
  [bulk_moles_H2O]
    type = GeochemistryQuantityAux
    species = 'H2O'
    reactor = reactor
    variable = bulk_moles_H2O
    quantity = bulk_moles
  []
  [pH]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = pH
    quantity = neglog10a
  []
  [molal_H+]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = 'molal_H+'
    quantity = molal
  []
  [molal_Cl-]
    type = GeochemistryQuantityAux
    species = 'Cl-'
    reactor = reactor
    variable = 'molal_Cl-'
    quantity = molal
  []
  [molal_HCl]
    type = GeochemistryQuantityAux
    species = 'HCl'
    reactor = reactor
    variable = 'molal_HCl'
    quantity = molal
  []
  [molal_OH-]
    type = GeochemistryQuantityAux
    species = 'OH-'
    reactor = reactor
    variable = 'molal_OH-'
    quantity = molal
  []
  [mg_per_kg_H+]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = 'mg_per_kg_H+'
    quantity = mg_per_kg
  []
  [mg_per_kg_Cl-]
    type = GeochemistryQuantityAux
    species = 'Cl-'
    reactor = reactor
    variable = 'mg_per_kg_Cl-'
    quantity = mg_per_kg
  []
  [mg_per_kg_HCl]
    type = GeochemistryQuantityAux
    species = 'HCl'
    reactor = reactor
    variable = 'mg_per_kg_HCl'
    quantity = mg_per_kg
  []
  [mg_per_kg_OH-]
    type = GeochemistryQuantityAux
    species = 'OH-'
    reactor = reactor
    variable = 'mg_per_kg_OH-'
    quantity = mg_per_kg
  []
  [activity_H+]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = 'activity_H+'
    quantity = activity
  []
  [activity_Cl-]
    type = GeochemistryQuantityAux
    species = 'Cl-'
    reactor = reactor
    variable = 'activity_Cl-'
    quantity = activity
  []
  [activity_HCl]
    type = GeochemistryQuantityAux
    species = 'HCl'
    reactor = reactor
    variable = 'activity_HCl'
    quantity = activity
  []
  [activity_OH-]
    type = GeochemistryQuantityAux
    species = 'OH-'
    reactor = reactor
    variable = 'activity_OH-'
    quantity = activity
  []
  [bulk_moles_H+]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = 'bulk_moles_H+'
    quantity = bulk_moles
  []
  [bulk_moles_Cl-]
    type = GeochemistryQuantityAux
    species = 'Cl-'
    reactor = reactor
    variable = 'bulk_moles_Cl-'
    quantity = bulk_moles
  []
  [bulk_moles_HCl]
    type = GeochemistryQuantityAux
    species = 'HCl'
    reactor = reactor
    variable = 'bulk_moles_HCl'
    quantity = bulk_moles
  []
  [bulk_moles_OH-]
    type = GeochemistryQuantityAux
    species = 'OH-'
    reactor = reactor
    variable = 'bulk_moles_OH-'
    quantity = bulk_moles
  []
[]

[Postprocessors]
  [pH]
    type = PointValue
    variable = 'pH'
  []
  [solvent_mass]
    type = PointValue
    variable = 'kg_solvent_H2O'
  []
  [molal_Cl-]
    type = PointValue
    variable = 'molal_Cl-'
  []
  [mg_per_kg_HCl]
    type = PointValue
    variable = 'mg_per_kg_HCl'
  []
  [activity_OH-]
    type = PointValue
    variable = 'activity_OH-'
  []
  [bulk_H+]
    type = PointValue
    variable = 'bulk_moles_H+'
  []
  [temperature]
    type = PointValue
    variable = 'solution_temperature'
  []
[]

[Executioner]
  type = Steady
[]

[UserObjects]
  [definition]
    type = GeochemicalModelDefinition
    database_file = "../../../database/moose_geochemdb.json"
    basis_species = "H2O H+ Cl-"
    piecewise_linear_interpolation = true # to reproduce the GWB result
  []
  [reactor]
    type = GeochemistryTimeDependentReactor
    model_definition = definition
    charge_balance_species = "Cl-"
    constraint_species = "H2O              H+            Cl-"
    constraint_value = "  1.0              -2            1E-2"
    constraint_meaning = "kg_solvent_water log10activity bulk_composition"
    constraint_unit = "   kg               dimensionless moles"
    ramp_max_ionic_strength_initial = 0 # max_ionic_strength in such a simple problem does not need ramping
    abs_tol = 1E-15
  []
  [nnn]
    type = NearestNodeNumberUO
  []
[]

[Outputs]
  csv = true
  [console_output]
    type = GeochemistryConsoleOutput
    geochemistry_reactor = reactor
    nearest_node_number_UO = nnn
    solver_info = true
    execute_on = initial
  []
[]

(test/tests/outputs/debug/show_execution_userobjects.i)

[Mesh]
  [cmg]
    type = CartesianMeshGenerator
    dim = 2
    dx = '1.5 2.4'
    dy = '1.3 0.9'
    ix = '3 2'
    iy = '2 3'
    subdomain_id = '0 1
                    1 0'
  []
  [add_interface]
    type = SideSetsBetweenSubdomainsGenerator
    input = 'cmg'
    primary_block = 0
    paired_block = 1
    new_boundary = 'interface'
  []
  second_order = true
[]

[Functions]
  [forcing_fnu]
    type = ParsedFunction
    expression = -5.8*(x+y)+x*x*x-x+y*y*y-y
  []
  [forcing_fnv]
    type = ParsedFunction
    expression = -4
  []

  [slnu]
    type = ParsedGradFunction
    expression = x*x*x-x+y*y*y-y
    grad_x = 3*x*x-1
    grad_y = 3*y*y-1
  []
  [slnv]
    type = ParsedGradFunction
    expression = x*x+y*y
    grad_x = 2*x
    grad_y = 2*y
  []

  # NeumannBC functions
  [bc_fnut]
    type = ParsedFunction
    expression = 3*y*y-1
  []
  [bc_fnub]
    type = ParsedFunction
    expression = -3*y*y+1
  []
  [bc_fnul]
    type = ParsedFunction
    expression = -3*x*x+1
  []
  [bc_fnur]
    type = ParsedFunction
    expression = 3*x*x-1
  []
[]

[Variables]
  [u]
    order = SECOND
    family = HIERARCHIC
  []
  [v]
    order = SECOND
    family = LAGRANGE
    initial_condition = 1
  []
[]

[AuxVariables]
  [v_elem]
    order = CONSTANT
    family = MONOMIAL
  []
[]

[Kernels]
  active = 'diff1 diff2 test1 forceu forcev react'
  [diff1]
    type = Diffusion
    variable = u
  []
  [test1]
    type = CoupledConvection
    variable = u
    velocity_vector = v
  []
  [diff2]
    type = Diffusion
    variable = v
  []
  [react]
    type = Reaction
    variable = u
  []

  [forceu]
    type = BodyForce
    variable = u
    function = forcing_fnu
  []
  [forcev]
    type = BodyForce
    variable = v
    function = forcing_fnv
  []
[]

[AuxKernels]
  [set_v_elem]
    type = FunctionAux
    variable = v_elem
    # selected not to be the solution for no particular reason
    function = forcing_fnv
  []
[]

[BCs]
  [bc_v]
    type = FunctionDirichletBC
    variable = v
    function = slnv
    boundary = 'left right top bottom'
  []
  [bc_u_tb]
    type = CoupledKernelGradBC
    variable = u
    var2 = v
    vel = '0.1 0.1'
    boundary = 'top bottom left right'
  []
  [bc_ul]
    type = FunctionNeumannBC
    variable = u
    function = bc_fnul
    boundary = 'left'
  []
  [bc_ur]
    type = FunctionNeumannBC
    variable = u
    function = bc_fnur
    boundary = 'right'
  []
  [bc_ut]
    type = FunctionNeumannBC
    variable = u
    function = bc_fnut
    boundary = 'top'
  []
  [bc_ub]
    type = FunctionNeumannBC
    variable = u
    function = bc_fnub
    boundary = 'bottom'
  []
[]

[Postprocessors]
  # Global user objects
  [dofs]
    type = NumDOFs
  []
  [h]
    type = AverageElementSize
  []

  # Elemental user objects
  [L2u]
    type = ElementL2Error
    variable = u
    function = slnu
    # Testing an option
    force_preic = true
  []
  [L2v]
    type = ElementL2Error
    variable = v
    function = slnv
    # Testing an option
    force_preaux = true
  []
  [H1error]
    type = ElementH1Error
    variable = u
    function = slnu
  []
  [H1Semierror]
    type = ElementH1SemiError
    variable = u
    function = slnu
  []
  [L2v_elem]
    type = ElementL2Error
    variable = v_elem
    function = slnv
  []
  [f_integral]
    type = FunctionElementIntegral
    function = slnv
  []
  [int_v]
    type = ElementIntegralVariablePostprocessor
    variable = v
    block = 1
    execute_on = 'TIMESTEP_END transfer'
  []
  [int_v_elem]
    type = ElementIntegralVariablePostprocessor
    variable = v_elem
    block = 1
    execute_on = 'TIMESTEP_END transfer'
  []

  # Side user objects
  [integral_v]
    type = SideIntegralVariablePostprocessor
    variable = v
    boundary = 0
  []
[]

[VectorPostprocessors]
  # General UOs
  [memory]
    type = VectorMemoryUsage
  []
  [line]
    type = LineValueSampler
    variable = v
    num_points = 10
    start_point = '0 0 0'
    end_point = '0.5 0.5 0'
    sort_by = 'x'
  []

  # Nodal UOs
  [nodal_sampler_y]
    type = NodalValueSampler
    variable = v
    sort_by = 'y'
  []
  [nodal_sampler_x]
    type = NodalValueSampler
    variable = v
    sort_by = 'x'
  []

  # Element UO
  [elem_sample]
    type = ElementValueSampler
    variable = v_elem
    sort_by = 'x'
  []
[]

[UserObjects]
  # Nodal user objects
  [find_node]
    type = NearestNodeNumberUO
    point = '0.5 0.5 0'
  []

  # Side user objects
  [side_int]
    type = LayeredSideIntegral
    variable = v
    boundary = 0
    direction = y
    num_layers = 4
  []
  [side_int_2]
    type = NearestPointLayeredSideIntegral
    variable = v
    boundary = 0
    direction = x
    num_layers = 3
    points = '1 1 0'
  []

  # Interface user objects
  [values]
    type = InterfaceQpValueUserObject
    var = v
    boundary = interface
  []

  inactive = 'prime_1 prime_2'
  # Threaded general user objects
  [prime_2]
    type = PrimeProductUserObject
  []
  [prime_1]
    type = PrimeProductUserObject
  []

  # Domain user objects
  [domain_2]
    type = InterfaceDomainUserObject
    u = u
    v = v
    block = '0'
    robin_boundaries = 'left'
    interface_boundaries = 'interface'
    interface_penalty = 1e-10
    nl_abs_tol = 1e1
  []
  [domain_1]
    type = InterfaceDomainUserObject
    u = u
    v = v
    block = '0 1'
    robin_boundaries = 'left'
    interface_boundaries = 'interface'
    interface_penalty = 1e-10
    nl_abs_tol = 1e1
  []
[]

[Executioner]
  type = Steady
  solve_type = 'PJFNK'
  nl_rel_tol = 1e-10
  nl_abs_tol = 1e-10
  l_tol = 1e-5
[]

[Problem]
  kernel_coverage_check = false
[]

[MultiApps]
  active = ''
  [full_solve]
    type = FullSolveMultiApp
    execute_on = 'initial timestep_end final'
    input_files = show_execution_userobjects.i
    cli_args = 'Problem/solve=false'
  []
[]

[Transfers]
  active = ''
  [conservative]
    type = MultiAppNearestNodeTransfer
    from_multi_app = full_solve
    source_variable = v
    variable = v_elem
    from_postprocessors_to_be_preserved = int_v
    to_postprocessors_to_be_preserved = int_v_elem
  []
[]

[Debug]
  show_execution_order = 'ALWAYS INITIAL NONLINEAR LINEAR TIMESTEP_BEGIN TIMESTEP_END FINAL'
[]

(test/tests/postprocessors/nearest_node_number/nearest_node_number_3.i)

# Using NearestNodeNumber, finds the node number of the nearest node to the point in the mesh
# In this case, the point is coincident with node number 1, but then adaptivity changes this
[Mesh]
  type = GeneratedMesh
  dim = 2
  ny = 1
  nx = 4
  xmax = 8

  # For consistency with distributed mesh
  allow_renumbering = false
[]

[Adaptivity]
  marker = marker
  [Markers]
  [marker]
    type = BoxMarker
    bottom_left = '0 0 0'
    top_right = '8 1 0'
    inside = refine
    outside = do_nothing
  []
[]
[]

[UserObjects]
  [nnn_uo]
    type = NearestNodeNumberUO
    point = '2 0 0'
    execute_on = 'initial timestep_begin'
  []
[]
[Postprocessors]
  [nnn]
    type = NearestNodeNumber
    nearest_node_number_uo = nnn_uo
    execute_on = 'initial timestep_begin'
  []
[]

[Problem]
  solve = false
[]

[Executioner]
  type = Transient
  end_time = 2
[]

[Outputs]
  csv = true
[]

(modules/geochemistry/test/tests/time_dependent_reactions/simple_no_action.i)

# This example is simple.i but without using an Action
# Simple example of time-dependent reaction path.
# This example involves an HCl solution that is initialized at pH=2, then the pH is controlled via controlled_activity, and finally HCl is titrated into the solution
[GlobalParams]
  point = '0 0 0'
[]

[Mesh]
  type = GeneratedMesh
  dim = 1
[]

[Problem]
  solve = false
[]

[AuxVariables]
  [act_H+]
  []
  [solution_temperature]
  []
  [kg_solvent_H2O]
  []
  [activity_H2O]
  []
  [bulk_moles_H2O]
  []
  [pH]
  []
  [molal_H+]
  []
  [molal_Cl-]
  []
  [molal_HCl]
  []
  [molal_OH-]
  []
  [mg_per_kg_H+]
  []
  [mg_per_kg_Cl-]
  []
  [mg_per_kg_HCl]
  []
  [mg_per_kg_OH-]
  []
  [activity_H+]
  []
  [activity_Cl-]
  []
  [activity_HCl]
  []
  [activity_OH-]
  []
  [bulk_moles_H+]
  []
  [bulk_moles_Cl-]
  []
  [bulk_moles_HCl]
  []
  [bulk_moles_OH-]
  []
[]

[AuxKernels]
  [act_H+]
    type = FunctionAux
    variable = act_H+
    function = '10^(-2 - t)'
    execute_on = timestep_begin
  []
  [solution_temperature]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = solution_temperature
    quantity = temperature
  []
  [kg_solvent_H2O]
    type = GeochemistryQuantityAux
    species = 'H2O'
    reactor = reactor
    variable = kg_solvent_H2O
    quantity = molal
  []
  [activity_H2O]
    type = GeochemistryQuantityAux
    species = 'H2O'
    reactor = reactor
    variable = activity_H2O
    quantity = activity
  []
  [bulk_moles_H2O]
    type = GeochemistryQuantityAux
    species = 'H2O'
    reactor = reactor
    variable = bulk_moles_H2O
    quantity = bulk_moles
  []
  [pH]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = pH
    quantity = neglog10a
  []
  [molal_H+]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = 'molal_H+'
    quantity = molal
  []
  [molal_Cl-]
    type = GeochemistryQuantityAux
    species = 'Cl-'
    reactor = reactor
    variable = 'molal_Cl-'
    quantity = molal
  []
  [molal_HCl]
    type = GeochemistryQuantityAux
    species = 'HCl'
    reactor = reactor
    variable = 'molal_HCl'
    quantity = molal
  []
  [molal_OH-]
    type = GeochemistryQuantityAux
    species = 'OH-'
    reactor = reactor
    variable = 'molal_OH-'
    quantity = molal
  []
  [mg_per_kg_H+]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = 'mg_per_kg_H+'
    quantity = mg_per_kg
  []
  [mg_per_kg_Cl-]
    type = GeochemistryQuantityAux
    species = 'Cl-'
    reactor = reactor
    variable = 'mg_per_kg_Cl-'
    quantity = mg_per_kg
  []
  [mg_per_kg_HCl]
    type = GeochemistryQuantityAux
    species = 'HCl'
    reactor = reactor
    variable = 'mg_per_kg_HCl'
    quantity = mg_per_kg
  []
  [mg_per_kg_OH-]
    type = GeochemistryQuantityAux
    species = 'OH-'
    reactor = reactor
    variable = 'mg_per_kg_OH-'
    quantity = mg_per_kg
  []
  [activity_H+]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = 'activity_H+'
    quantity = activity
  []
  [activity_Cl-]
    type = GeochemistryQuantityAux
    species = 'Cl-'
    reactor = reactor
    variable = 'activity_Cl-'
    quantity = activity
  []
  [activity_HCl]
    type = GeochemistryQuantityAux
    species = 'HCl'
    reactor = reactor
    variable = 'activity_HCl'
    quantity = activity
  []
  [activity_OH-]
    type = GeochemistryQuantityAux
    species = 'OH-'
    reactor = reactor
    variable = 'activity_OH-'
    quantity = activity
  []
  [bulk_moles_H+]
    type = GeochemistryQuantityAux
    species = 'H+'
    reactor = reactor
    variable = 'bulk_moles_H+'
    quantity = bulk_moles
  []
  [bulk_moles_Cl-]
    type = GeochemistryQuantityAux
    species = 'Cl-'
    reactor = reactor
    variable = 'bulk_moles_Cl-'
    quantity = bulk_moles
  []
  [bulk_moles_HCl]
    type = GeochemistryQuantityAux
    species = 'HCl'
    reactor = reactor
    variable = 'bulk_moles_HCl'
    quantity = bulk_moles
  []
  [bulk_moles_OH-]
    type = GeochemistryQuantityAux
    species = 'OH-'
    reactor = reactor
    variable = 'bulk_moles_OH-'
    quantity = bulk_moles
  []
[]

[Postprocessors]
  [pH]
    type = PointValue
    variable = 'pH'
  []
  [solvent_mass]
    type = PointValue
    variable = 'kg_solvent_H2O'
  []
  [molal_Cl-]
    type = PointValue
    variable = 'molal_Cl-'
  []
  [mg_per_kg_HCl]
    type = PointValue
    variable = 'mg_per_kg_HCl'
  []
  [activity_OH-]
    type = PointValue
    variable = 'activity_OH-'
  []
  [bulk_H+]
    type = PointValue
    variable = 'bulk_moles_H+'
  []
  [temperature]
    type = PointValue
    variable = 'solution_temperature'
  []
[]

[Executioner]
  type = Transient
  dt = 1
  end_time = 10
[]

[UserObjects]
  [definition]
    type = GeochemicalModelDefinition
    database_file = "../../../database/moose_geochemdb.json"
    basis_species = "H2O H+ Cl-"
  []
  [reactor]
    type = GeochemistryTimeDependentReactor
    model_definition = definition
    charge_balance_species = "Cl-"
    constraint_species = "H2O              H+            Cl-"
    constraint_value = "  1.0              -2            1E-2"
    constraint_meaning = "kg_solvent_water log10activity bulk_composition"
    constraint_unit = "   kg               dimensionless moles"
    ramp_max_ionic_strength_initial = 0 # max_ionic_strength in such a simple problem does not need ramping

# close the system at time = 0
    close_system_at_time = 0

# control pH.  This sets pH = 2 + t (see the act_H+ AuxKernel)
    controlled_activity_name = 'H+'
    controlled_activity_value = 'act_H+'

# remove the constraint on H+ activity at time = 5, when, from the previous time-step, pH = 2 + 4 = 6
    remove_fixed_activity_name = 'H+'
    remove_fixed_activity_time = 5

# add 1E-5 moles of HCl every second of the simulation: this has no impact before time = 5 when the fixed-activity constraint it turned off, but then, molality_H+ ~ 1E-6 + 1E-4 * (t - 4), so
# time, approx_pH
# 5, -log10(1E-4) = 4
# 10, -log10(6E-4) = 3.2
    source_species_names = 'HCl'
    source_species_rates = '1E-4'
  []
  [nnn]
    type = NearestNodeNumberUO
  []
[]

[Outputs]
  csv = true
  file_base = simple_out
  [console_output]
    type = GeochemistryConsoleOutput
    geochemistry_reactor = reactor
    nearest_node_number_UO = nnn
    solver_info = true
    execute_on = 'final'
  []
[]

(test/tests/postprocessors/nearest_node_number/nearest_node_number_1.i)

# Using NearestNodeNumber, finds the node number of the nearest node to the point in the mesh
# In this case, the point is coincident with node number 1
[Mesh]
  type = GeneratedMesh
  dim = 1
  nx = 4
  xmax = 8

  # For consistency with distributed mesh
  allow_renumbering = false
[]

[UserObjects]
  [nnn_uo]
    type = NearestNodeNumberUO
    point = '2 0 0'
    execute_on = 'initial timestep_begin'
  []
[]
[Postprocessors]
  [nnn]
    type = NearestNodeNumber
    nearest_node_number_uo = nnn_uo
    execute_on = 'initial timestep_begin'
  []
[]

[Problem]
  solve = false
[]

[Executioner]
  type = Transient
  end_time = 2
[]

[Outputs]
  csv = true
[]

Input Parameters
Input Files