DefaultSteadyStateConvergence

This Convergence is the default convergence for steady-state detection in Transient. The relative discrete L2 norm of the difference of all of the variables, either from the solution vector or from the auxiliary system, is compared to a tolerance to determine convergence:

var element = document.getElementById("moose-equation-7ece1abe-0fff-4be8-be0a-0e2f25c530bf");katex.render("\\|\\mathbf{u}^{n+1} - \\mathbf{u}^n\\|_2 < \\tau \\|\\mathbf{u}^{n+1}\\|_2 \\,,", 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

$var element = document.getElementById("moose-equation-d4abe7e2-b62b-4cf1-9da4-d44c2ef24ac9");katex.render("\\mathbf{u}", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the discrete variables vector. If "check_aux" is set to true, then the auxiliary system variables are used; else, the solution variables are used.
$var element = document.getElementById("moose-equation-c8ec3644-8a83-4566-b1d1-f4a35a3b2c4d");katex.render("n", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the time step index.
$var element = document.getElementById("moose-equation-8d2dd84b-d2c3-4f1f-83e6-79e561f74a9a");katex.render("\\tau", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the tolerance, specified by "steady_state_tolerance".

note:Auxiliary variables treated variable-wise

Note that when the auxiliary system is used, the L2 norms are computed for each variable separately, and then the maximum over all variables is used. This difference of behavior is to achieve backwards compatibility.

If "normalize_solution_diff_norm_by_dt" is set to true, then the norm is normalized by the time step size:

var element = document.getElementById("moose-equation-67b48790-5327-422e-b1c5-cb436def7b6e");katex.render("\\frac{\\|\\mathbf{u}^{n+1} - \\mathbf{u}^n\\|_2}{\\Delta t} < \\tau \\|\\mathbf{u}^{n+1}\\|_2 \\,.", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});

Input Parameters

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

check_auxFalseWhether to check the auxiliary system for convergence to steady-state. If false, then the solution vector from the solver system is used.
Default:False
C++ Type:bool
Controllable:No
Description:Whether to check the auxiliary system for convergence to steady-state. If false, then the solution vector from the solver system is used.
normalize_solution_diff_norm_by_dtTrueWhether to divide the solution difference norm by dt. If taking 'small' time steps you probably want this to be true. If taking very 'large' timesteps in an attempt to *reach* a steady-state, you probably want this parameter to be false.
Default:True
C++ Type:bool
Controllable:No
Description:Whether to divide the solution difference norm by dt. If taking 'small' time steps you probably want this to be true. If taking very 'large' timesteps in an attempt to *reach* a steady-state, you probably want this parameter to be false.
steady_state_tolerance1e-08Whenever the relative residual changes by less than this the solution will be considered to be at steady state.
Default:1e-08
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Whenever the relative residual changes by less than this the solution will be considered to be at steady state.

Steady State Detection 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/default_steady_state_convergence/default.i)

(test/tests/convergence/default_steady_state_convergence/default.i)

!include base.i

[Convergence]
  [steady_conv]
    type = DefaultSteadyStateConvergence
    steady_state_tolerance = ${ss_tol}
  []
[]

Input Parameters
Input Files