Subdomain modification

[PEI0214]

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Question

Hello
When I modified the subdomain using TimedSubdomainModifier, the displacement continued to increase at each time step. When I use CoupledVarThresholdElementSubdomainModifier modify domain, this will not happen. What causes this? Do you have any good suggestions? The input file and the results are as follows:

Test1.i

[Problem]
  kernel_coverage_check = false
  material_coverage_check = false
[]

Box1_inactive_id = '2'
inactive_domain_block_ids = '${Box1_inactive_id}'

[Mesh]
  [BaseMesh]
    type = GeneratedMeshGenerator
    dim = 3
    nx = 10
    ny = 10
    nz = 30
    xmin = -0.5
    xmax = +0.5
    ymin = -0.5
    ymax = +0.5
    zmin = 0
    zmax = +3
  []

  add_subdomain_ids = ${inactive_domain_block_ids}
[]

[GlobalParams]
  displacements = 'disp_x disp_y disp_z'
  use_displaced_mesh = false
[]

[Variables]
  [disp_x]
    block = '0 ${inactive_domain_block_ids}'
  []
  [disp_y]
    block = '0 ${inactive_domain_block_ids}'
  []
  [disp_z]
    block = '0 ${inactive_domain_block_ids}'
  []
[]

[Physics]
  [SolidMechanics]
    [QuasiStatic]
      [all]
        strain = finite
        add_variables = true
        generate_output = 'stress_xx stress_yy stress_zz stress_xz strain_xx strain_yy strain_zz'
        block = ${inactive_domain_block_ids}
      []
    []
  []
[]

# ===== Gravity =====
[Kernels]
  [Gravity1]
    type = Gravity
    block = ${inactive_domain_block_ids}
    use_displaced_mesh = false
    variable = disp_z
    value = -10
  []
[]

# ===== Boundary Conditions =====
[BCs]
  [archor_x]
    type = DirichletBC
    boundary = 'back'
    variable = disp_x
    value = 0
  []

  [archor_y]
    type = DirichletBC
    boundary = 'back'
    variable = disp_y
    value = 0
  []

  [archor_z]
    type = DirichletBC
    boundary = 'back'
    variable = disp_z
    value = 0
  []
[]

# ===== Materials (linear-elastic to keep it simple) =====
[Materials]
  [elasticity_tensor1]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 50E6 # 50 MPa
    poissons_ratio = 0.3
    block = ${inactive_domain_block_ids}
  []

  [stress]
    type = ComputeFiniteStrainElasticStress
    block = ${inactive_domain_block_ids}
  []

  [density1]
    type = GenericConstantMaterial
    prop_names = density
    prop_values = 2000
    block = ${inactive_domain_block_ids}
  []
[]

[UserObjects]
  [GlobalSubdomainModifier]
    type = TimedSubdomainModifier
    times = '2'
    blocks_from = '0'
    blocks_to = '2'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
  []
[]

# ===== Executioner =====
[Executioner]
  type = Transient
  # automatic_scaling = true

  end_time = 5
  dt = 1

  solve_type = 'PJFNK'
  petsc_options = '-snes_converged_reason'
  petsc_options_iname = '-pc_type -pc_factor_mat_solver_package'
  petsc_options_value = ' lu       mumps'

  nl_abs_tol = 1E-3
  nl_max_its = 400

  l_tol = 1E-3
  l_max_its = 200
[]

[Outputs]
  exodus = true
[]

[Debug]
  show_var_residual_norms = true
[]

test1.mp4

Test2.i

[Problem]
  kernel_coverage_check = false
  material_coverage_check = false
[]

Box1_inactive_id = '2'
inactive_domain_block_ids = '${Box1_inactive_id}'

[Mesh]
  [BaseMesh]
    type = GeneratedMeshGenerator
    dim = 3
    nx = 10
    ny = 10
    nz = 30
    xmin = -0.5
    xmax = +0.5
    ymin = -0.5
    ymax = +0.5
    zmin = 0
    zmax = +3
  []

  add_subdomain_ids = ${inactive_domain_block_ids}
[]

[GlobalParams]
  displacements = 'disp_x disp_y disp_z'
  use_displaced_mesh = false
[]

[Variables]
  [disp_x]
    block = '0 ${inactive_domain_block_ids}'
  []
  [disp_y]
    block = '0 ${inactive_domain_block_ids}'
  []
  [disp_z]
    block = '0 ${inactive_domain_block_ids}'
  []
[]

[Physics]
  [SolidMechanics]
    [QuasiStatic]
      [all]
        strain = finite
        add_variables = true
        generate_output = 'stress_xx stress_yy stress_zz stress_xz strain_xx strain_yy strain_zz'
        block = ${inactive_domain_block_ids}
      []
    []
  []
[]

# ===== Gravity =====
[Kernels]
  [Gravity1]
    type = Gravity
    block = ${inactive_domain_block_ids}
    use_displaced_mesh = false
    variable = disp_z
    value = -10
  []
[]

# ===== Boundary Conditions =====
[BCs]
  [archor_x]
    type = DirichletBC
    boundary = 'back'
    variable = disp_x
    value = 0
  []

  [archor_y]
    type = DirichletBC
    boundary = 'back'
    variable = disp_y
    value = 0
  []

  [archor_z]
    type = DirichletBC
    boundary = 'back'
    variable = disp_z
    value = 0
  []
[]

# ===== Materials (linear-elastic to keep it simple) =====
[Materials]
  [elasticity_tensor1]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 50E6 # 50 MPa
    poissons_ratio = 0.3
    block = ${inactive_domain_block_ids}
  []

  [stress]
    type = ComputeFiniteStrainElasticStress
    block = ${inactive_domain_block_ids}
  []

  [density1]
    type = GenericConstantMaterial
    prop_names = density
    prop_values = 2000
    block = ${inactive_domain_block_ids}
  []
[]


# ===== Block Activation/Deactivation =====
[Functions]
  [Box1_ActivationStateFunction]
    type = PiecewiseConstant
    direction = left
    xy_data = '0  1
               1  1
               2  0
               5  0'
  []
[]

[AuxVariables]
  [Box1_Activation_AuxVariable]
    family = MONOMIAL
    order = CONSTANT
  []
[]

[AuxKernels]
  [Box1_Activation_FunctionAux]
    type = FunctionAux
    variable = 'Box1_Activation_AuxVariable'
    function = 'Box1_ActivationStateFunction'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
  []
[]

[UserObjects]
  [Box1_SubdomainModifier]
    type = CoupledVarThresholdElementSubdomainModifier
    coupled_var = 'Box1_Activation_AuxVariable'
    criterion_type = ABOVE
    threshold = 0.5
    block = 0
    subdomain_id = 0
    complement_subdomain_id = ${Box1_inactive_id}
    execute_on = 'INITIAL TIMESTEP_BEGIN'
  []
[]

# ===== Executioner =====
[Executioner]
  type = Transient
  # automatic_scaling = true

  end_time = 5
  dt = 1

  solve_type = 'PJFNK'
  petsc_options = '-snes_converged_reason'
  petsc_options_iname = '-pc_type -pc_factor_mat_solver_package'
  petsc_options_value = ' lu       mumps'

  nl_abs_tol = 1E-3
  nl_max_its = 400

  l_tol = 1E-3
  l_max_its = 200
[]

[Outputs]
  exodus = true
[]

[Debug]
  show_var_residual_norms = true
[]

test2.mp4

[GiudGiud]

Duplicate post of #28521