InternalVolume

Computes the volume of an enclosed area by performing an integral over a user-supplied boundary.

Description

InternalVolume computes the volume of an enclosed space. The complete boundary of the enclosed space must be represented by the user specified side set. The volume of the domain is calculated as the integral over the surface of the domain, where the domain surface is specified by the boundary.

If the given side set points outward, InternalVolume will report a negative volume.

As an example, consider $var element = document.getElementById("moose-equation-0988853a-4874-425c-b8ba-cbfb5a1996f7");katex.render("\\int_V div(F) dV = \\int_{dS} F \\cdot \\hat{n} dS", element, {displayMode:true,throwOnError:false});$ where $var element = document.getElementById("moose-equation-52022b36-68ff-4a18-aa6c-435f0a0aa68d");katex.render("F", element, {displayMode:false,throwOnError:false});$ is a field, $var element = document.getElementById("moose-equation-a8cc86ea-52d2-4847-8b09-c845e565f371");katex.render("\\hat{n}", element, {displayMode:false,throwOnError:false});$ is the normal of the surface, $var element = document.getElementById("moose-equation-305f4f56-5431-4c8d-b647-acc881e8c7dd");katex.render("V", element, {displayMode:false,throwOnError:false});$ is the volume of the domain, and $var element = document.getElementById("moose-equation-2e0536e7-a9fa-472b-8428-dad95dc55cf9");katex.render("S", element, {displayMode:false,throwOnError:false});$ is the surface of the domain.

For simplicity in this example, we choose $var element = document.getElementById("moose-equation-c82b30fc-d822-493b-b3d2-e26ef310dc05");katex.render("F = \\left[ x, 0, 0 \\right]^T \\quad \\text{then} \\quad div(F) = 1", element, {displayMode:true,throwOnError:false});$

such that the integral becomes

$var element = document.getElementById("moose-equation-88fcf888-afc9-4ac1-93a2-9a69164525f9");katex.render("\\int_V dV = \\int_{dS} x \\cdot n[0] dS", element, {displayMode:true,throwOnError:false});$

The volume of the domain is the integral over the surface of the domain of the x position of the surface times the x-component of the normal of the surface.

Example Input Syntax

  [./internalVolume]
    type = InternalVolume
    boundary = 100
    addition = addition
    execute_on = 'initial timestep_end'
  [../]

Input Parameters

boundaryThe list of boundary IDs from the mesh where this boundary condition applies
C++ Type:std::vector<BoundaryName>
Options:
Description:The list of boundary IDs from the mesh where this boundary condition applies

Required Parameters

addition0An additional volume to be included in the internal volume calculation. A time-dependent function is expected.
Default:0
C++ Type:FunctionName
Options:
Description:An additional volume to be included in the internal volume calculation. A time-dependent function is expected.
component0The component to use in the integration
Default:0
C++ Type:unsigned int
Options:
Description:The component to use in the integration
execute_onTIMESTEP_ENDThe list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM.
Default:TIMESTEP_END
C++ Type:ExecFlagEnum
Options:NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM, TRANSFER
Description:The list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM.
scale_factor1A scale factor to be applied to the internal volume calculation
Default:1
C++ Type:double
Options:
Description:A scale factor to be applied to the internal volume calculation

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
Options:
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).
control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Options:
Description:Adds user-defined labels for accessing object parameters via control logic.
enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Options:
Description:Set the enabled status of the MooseObject.
outputsVector of output names were you would like to restrict the output of variables(s) associated with this object
C++ Type:std::vector<OutputName>
Options:
Description:Vector of output names were you would like to restrict the output of variables(s) associated with this object
use_displaced_meshTrueWhether 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:True
C++ Type:bool
Options:
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

(moose/modules/combined/test/tests/internal_volume/hex8.i)

#
# Internal Volume Test
#
# This test is designed to compute the internal volume of a space considering
#   an embedded volume inside.
#
# The mesh is composed of one block (1) with an interior cavity of volume 8.
#   Block 2 sits in the cavity and has a volume of 1.  Thus, the total volume
#   is 7.
#
# The internal volume is then adjusted by a piecewise linear time varying
# function.  Thus, the total volume is 7 plus the addition at the particular
# time.
#
#  Time |  Addition  | Total volume
#   0   |    0.0     |     7.0
#   1   |    3.0     |    10.0
#   2   |    7.0     |    14.0
#   3   |   -3.0     |     4.0
#
[GlobalParams]
  displacements = 'disp_x disp_y disp_z'
[]

[Mesh]
  file = meshes/hex8.e
[]

[Functions]
  [./step]
    type = PiecewiseLinear
    x = '0. 1. 2. 3.'
    y = '0. 0. 1e-2 0.'
    scale_factor = 0.5
  [../]
  [./addition]
    type = PiecewiseLinear
    x = '0. 1. 2. 3.'
    y = '0. 3. 7. -3.'
  [../]
[]

[Variables]
  [./disp_x]
    order = FIRST
    family = LAGRANGE
  [../]

  [./disp_y]
    order = FIRST
    family = LAGRANGE
  [../]

  [./disp_z]
    order = FIRST
    family = LAGRANGE
  [../]
[]

[Modules/TensorMechanics/Master]
  [./all]
    volumetric_locking_correction = true
    incremental = true
    strain = FINITE
  [../]
[]

[BCs]
  [./no_x]
    type = DirichletBC
    variable = disp_x
    boundary = 100
    value = 0.0
  [../]

  [./no_y]
    type = DirichletBC
    variable = disp_y
    boundary = 100
    value = 0.0
  [../]

  [./prescribed_z]
    type = FunctionDirichletBC
    variable = disp_z
    boundary = 100
    function = step
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    block = '1 2'
    youngs_modulus = 1e6
    poissons_ratio = 0.3
  [../]

  [./stress]
    type = ComputeFiniteStrainElasticStress
    block = '1 2'
  [../]
[]

[Executioner]
  type = Transient
  solve_type = 'PJFNK'

  start_time = 0.0
  dt = 1.0
  end_time = 3.0
[]

[Postprocessors]
  [./internalVolume]
    type = InternalVolume
    boundary = 100
    addition = addition
    execute_on = 'initial timestep_end'
  [../]

  [./dispZ]
    type = ElementAverageValue
    block = '1 2'
    variable = disp_z
  [../]
[]

[Outputs]
  exodus = true
  csv = true
[]

Description
Example Input Syntax
Input Parameters