MFEMElementAverageValue

Overview

Computes the volumetric average of a scalar MFEM variable over the mesh or a block-restricted subset of subdomains:

var element = document.getElementById("moose-equation-df77d433-e144-4981-949e-bc9b7ae3699a");katex.render("\\bar{u} = \\frac{\\int_\\Omega u \\, \\mathrm{d}V}{\\int_\\Omega \\mathrm{d}V}", 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 $var element = document.getElementById("moose-equation-4dff691d-62b3-45a7-8e4f-214734c80ec2");katex.render("\\Omega", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is the full mesh domain, or the union of subdomains specified by "block".

Example Input File Syntax

[Postprocessors<<<{"href": "../../../syntax/Postprocessors/index.html"}>>>]
  [avg]
    type = MFEMElementAverageValue<<<{"description": "Computes the volumetric average of a scalar MFEM variable.", "href": "MFEMElementAverageValue.html"}>>>
    variable<<<{"description": "Name of the scalar variable to average."}>>> = u
    execute_on<<<{"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."}>>> = 'TIMESTEP_END'
  []
[]

Input Parameters

variableName of the scalar variable to average.
C++ Type:VariableName
Unit:(no unit assumed)
Controllable:No
Description:Name of the scalar variable to average.

Required Parameters

blockThe list of subdomains (names or ids) that this object will be restricted to. Leave empty to apply to all subdomains.
C++ Type:std::vector<SubdomainName>
Controllable:No
Description:The list of subdomains (names or ids) that this object will be restricted to. Leave empty to apply to all subdomains.
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, MULTISYSTEM_FIXED_POINT_ITERATION_END, FINAL, CUSTOM
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.

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.
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

Advanced Parameters

Input Files

(test/tests/mfem/meshgenerators/generated/test.i)

(test/tests/mfem/meshgenerators/generated/test.i)

[Mesh]
  [gen]
    type = MFEMGeneratedMeshGenerator
    dim = 1
    nx = 5
  []
[]

[Problem]
  type = MFEMProblem
[]

[FESpaces]
  [h1]
    type = MFEMScalarFESpace
    fec_type = H1
    fec_order = FIRST
  []
[]

[Variables]
  [u]
    type = MFEMVariable
    fespace = h1
  []
[]

[Kernels]
  [diff]
    type = MFEMDiffusionKernel
    variable = u
  []
[]

[BCs]
  [left]
    type = MFEMScalarDirichletBC
    variable = u
    boundary = 'left'
    coefficient = 0
  []
  [right]
    type = MFEMScalarDirichletBC
    variable = u
    boundary = 'right'
    coefficient = 1
  []
[]

[Solvers]
  [boomeramg]
    type = MFEMHypreBoomerAMG
  []
  [main]
    type = MFEMHypreGMRES
    preconditioner = boomeramg
    l_tol = 1e-12
    l_max_its = 100
  []
[]

[Executioner]
  type = MFEMSteady
  device = cpu
[]

[Postprocessors]
  [avg]
    type = MFEMElementAverageValue
    variable = u
    execute_on = 'TIMESTEP_END'
  []
[]

[Outputs]
  [out]
    type = CSV
    file_base = average
    execute_on = 'TIMESTEP_END'
  []
[]

(test/tests/mfem/meshgenerators/generated/test.i)

[Mesh]
  [gen]
    type = MFEMGeneratedMeshGenerator
    dim = 1
    nx = 5
  []
[]

[Problem]
  type = MFEMProblem
[]

[FESpaces]
  [h1]
    type = MFEMScalarFESpace
    fec_type = H1
    fec_order = FIRST
  []
[]

[Variables]
  [u]
    type = MFEMVariable
    fespace = h1
  []
[]

[Kernels]
  [diff]
    type = MFEMDiffusionKernel
    variable = u
  []
[]

[BCs]
  [left]
    type = MFEMScalarDirichletBC
    variable = u
    boundary = 'left'
    coefficient = 0
  []
  [right]
    type = MFEMScalarDirichletBC
    variable = u
    boundary = 'right'
    coefficient = 1
  []
[]

[Solvers]
  [boomeramg]
    type = MFEMHypreBoomerAMG
  []
  [main]
    type = MFEMHypreGMRES
    preconditioner = boomeramg
    l_tol = 1e-12
    l_max_its = 100
  []
[]

[Executioner]
  type = MFEMSteady
  device = cpu
[]

[Postprocessors]
  [avg]
    type = MFEMElementAverageValue
    variable = u
    execute_on = 'TIMESTEP_END'
  []
[]

[Outputs]
  [out]
    type = CSV
    file_base = average
    execute_on = 'TIMESTEP_END'
  []
[]

Overview
Example Input File Syntax
Input Parameters
Input Files