MultiPostprocessorConvergence

This Convergence derives from IterationCountConvergence and checks multiple post-processor values against tolerances:

var element = document.getElementById("moose-equation-2969d28d-8f7a-4369-8372-4f8c73793508");katex.render("|y| < \\tau_y", 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 $var element = document.getElementById("moose-equation-b90211aa-8305-4f02-8113-39ae74d53d2f");katex.render("y", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the checked post-processor quantity, and $var element = document.getElementById("moose-equation-6f36d0d8-a3f7-4bf5-b17e-c24faae8d217");katex.render("\\tau_y", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the associated tolerance.

The object returns CONVERGED if all of the checks are true and ITERATING otherwise.

For this to work as expected, the execute_on parameter of the post-processors must include values that trigger execution before the desired check. The following table lists general recommendations for which execute_on flags to include for each type of convergence check. See SetupInterface for details on different execution points.

Convergence Check	Recommended `execute_on`
Nonlinear	`NONLINEAR_CONVERGENCE`
Steady-state	`TIMESTEP_END`
MultiApp fixed point	`MULTIAPP_FIXED_POINT_CONVERGENCE` (see Residual for specific guidance for `Residual`)
Multi-system fixed point	`MULTISYSTEM_FIXED_POINT_CONVERGENCE`

note

The parameter "min_iterations" is recommended to be set $var element = document.getElementById("moose-equation-7ff6383f-2b8a-47b0-8c1d-30c150ad7112");katex.render("\\geq 1", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ whenever step criteria are used, since the step in the first iteration is always zero.

Input Parameters

postprocessorsPostprocessors to check
C++ Type:std::vector<PostprocessorName>
Unit:(no unit assumed)
Controllable:No
Description:Postprocessors to check
tolerancesTolerance for each Postprocessor
C++ Type:std::vector<double>
Unit:(no unit assumed)
Controllable:No
Description:Tolerance for each Postprocessor

Required Parameters

converge_at_max_iterationsFalseConverge at 'max_iterations' instead of diverging
Default:False
C++ Type:bool
Controllable:No
Description:Converge at 'max_iterations' instead of diverging
descriptionsDescription of each Postprocessor. If not provided, the Postprocessor names are used as their descriptions.
C++ Type:std::vector<std::string>
Controllable:No
Description:Description of each Postprocessor. If not provided, the Postprocessor names are used as their descriptions.
max_iterations50Maximum number of iterations
Default:50
C++ Type:unsigned int
Controllable:No
Description:Maximum number of iterations
min_iterations0Minimum number of iterations
Default:0
C++ Type:unsigned int
Controllable:No
Description:Minimum number of iterations
verboseFalseEnable printing of additional information, including convergence and divergence reasons.
Default:False
C++ Type:bool
Controllable:No
Description:Enable printing of additional information, including convergence and divergence reasons.

Optional 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:No
Description:Set the enabled status of the MooseObject.
implicitTrueDetermines whether this object is calculated using an implicit or explicit form
Default:True
C++ Type:bool
Controllable:No
Description:Determines whether this object is calculated using an implicit or explicit form

Advanced Parameters

Input Files

(test/tests/convergence/multi_postprocessor_convergence/multi_postprocessor_convergence.i)

(test/tests/convergence/multi_postprocessor_convergence/multi_postprocessor_convergence.i)

# pp1 converges (< 1e-6) at t=2
# pp2 converges (< 1e-7) at t=3
# Therefore, all converge at t=3, so expected number of dt=1 steps is 3.

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

[Functions]
  [pp1_fn]
    type = PiecewiseLinear
    x = '0    1    2    3    4    5'
    y = '1e-6 1e-3 1e-6 1e-7 1e-8 1e-9'
  []
  [pp2_fn]
    type = PiecewiseLinear
    x = '0    1    2    3    4    5'
    y = '1e-8 1e-6 1e-6 1e-8 1e-9 1e-9'
  []
[]

[Postprocessors]
  [pp1]
    type = FunctionValuePostprocessor
    function = pp1_fn
    execute_on = 'INITIAL TIMESTEP_END'
  []
  [pp2]
    type = FunctionValuePostprocessor
    function = pp2_fn
    execute_on = 'INITIAL TIMESTEP_END'
  []
[]

[Convergence]
  [ss_conv_with_descriptions]
    type = MultiPostprocessorConvergence
    postprocessors = 'pp1 pp2'
    descriptions = 'QuantityA QuantityB'
    tolerances = '1e-5 1e-7'
  []
  [ss_conv_without_descriptions]
    type = MultiPostprocessorConvergence
    postprocessors = 'pp1 pp2'
    tolerances = '1e-5 1e-7'
  []
  [ss_conv]
    type = ParsedConvergence
    convergence_expression = 'conv1 & conv2'
    symbol_names = 'conv1 conv2'
    symbol_values = 'ss_conv_with_descriptions ss_conv_without_descriptions'
  []
[]

[Problem]
  solve = false
[]

[Executioner]
  type = Transient
  dt = 1
  num_steps = 5
  steady_state_detection = true
  steady_state_convergence = ss_conv
  verbose = true
[]

[Outputs]
  [out]
    type = CSV
    execute_on = 'FINAL'
  []
[]

Input Parameters
Input Files