MovingPlanarFront

This function defines the position of a moving front. The front is an infinite plane with normal pointing from start_posn to end_posn. The front's distance from start_posn is defined by 'distance', so if the 'distance' function is time dependent, the front's position will change with time. Roughly speaking, the function returns true_value for points lying in between start_posn and start_posn + distance. Precisely speaking, two planes are constructed, both with normal pointing from start_posn to end_posn. The first plane passes through start_posn; the second plane passes through end_posn. Given a point p and time t, this function returns false_value if ANY of the following are true: (a) t<activation_time; (b) t>=deactivation_time; (c) p is 'behind' start_posn (ie, p lies on one side of the start_posn plane and end_posn lies on the other side); (d) p is 'ahead' of the front (ie, p lies one one side of the front and start_posn lies on the other side); (e) the distance between p and the front is greater than active_length. Otherwise, the point is 'in the active zone' and the function returns true_value.

Input Parameters

distanceThe front is an infinite plane with normal pointing from start_posn to end_posn. The front's distance from start_posn is defined by distance. You should ensure that distance is positive
C++ Type:FunctionName
Unit:(no unit assumed)
Controllable:No
Description:The front is an infinite plane with normal pointing from start_posn to end_posn. The front's distance from start_posn is defined by distance. You should ensure that distance is positive
end_posnFinal position of the front
C++ Type:libMesh::VectorValue<double>
Unit:(no unit assumed)
Controllable:No
Description:Final position of the front
start_posnInitial position of the front
C++ Type:libMesh::VectorValue<double>
Unit:(no unit assumed)
Controllable:No
Description:Initial position of the front

Required Parameters

activation_time-1.79769e+308This function will return false_value when t < activation_time
Default:-1.79769e+308
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:This function will return false_value when t < activation_time
active_length1.79769e+308Points greater than active_length behind the front will return false_value
Default:1.79769e+308
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Points greater than active_length behind the front will return false_value
deactivation_time1.79769e+308This function will return false_value when t >= deactivation_time
Default:1.79769e+308
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:This function will return false_value when t >= deactivation_time
false_value0Return this value if a point is not in the active zone.
Default:0
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Return this value if a point is not in the active zone.
true_value1Return this value if a point is in the active zone.
Default:1
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Return this value if a point is in the active zone.

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.

Advanced Parameters

Input Files

(modules/porous_flow/test/tests/functions/mpf1.i)
(modules/porous_flow/test/tests/functions/mpf_except1.i)

(modules/porous_flow/test/tests/functions/mpf1.i)

[Mesh]
  type = GeneratedMesh
  dim = 2
  nx = 15
  ny = 15
  xmin = 0
  xmax = 10
  ymin = 0
  ymax = 10
[]

[Variables]
  [u]
  []
[]

[Kernels]
  [dummy]
    type = TimeDerivative
    variable = u
  []
[]

[Functions]
  [dist]
    type = PiecewiseLinear
    x = '1 10'  # time
    y = '0 9'   # distance
  []
  [moving_planar_front]
    type = MovingPlanarFront
    start_posn = '1 1 0'
    end_posn = '2 2 0' # it does not matter that dist exceeds this
    active_length = 5
    activation_time = 1
    deactivation_time = 9
    distance = dist
  []
[]

[AuxVariables]
  [mpf]
  []
[]

[AuxKernels]
  [mpf]
    type = FunctionAux
    variable = mpf
    function = moving_planar_front
  []
[]

[Executioner]
  type = Transient
  dt = 0.5
  end_time = 10
[]

[Outputs]
  file_base = mpf1
  exodus = true
[]

(modules/porous_flow/test/tests/functions/mpf_except1.i)

[Mesh]
  type = GeneratedMesh
  dim = 3
  nx = 1
  ny = 1
  nz = 1
[]

[Variables]
  [u]
  []
[]

[Kernels]
  [dummy]
    type = TimeDerivative
    variable = u
  []
[]

[Functions]
  [moving_planar_front]
    type = MovingPlanarFront
    start_posn = '1 1 0'
    end_posn = '1 1 0'
    active_length = 1
    distance = t
  []
[]

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

[Outputs]
  file_base = mpf_except1.i
  exodus = true
[]

Input Parameters
Input Files