SphereMeshGenerator

Generate a sphere (ball) mesh centered on the origin

Overview

The SphereMeshGenerator creates a mesh of a sphere (a ball, not its boundary). The mesh refinement and smoothing parameters define the mesh density. Figure 1 depicts several sphere meshes (sliced in half to illustrate the interior elements) for different selections of refinement and smoothing parameters.

Figure 1: Sphere meshes created with different choices for refinement level and smoothing operations

The dimension of the generated mesh is determined by the selected elem_type. 3D element types will cause a ball volume to be meshed, 2D element types will cause a circular area (disk) to be meshed, and 1D element types will cause a line segment to be meshed.

Input Parameters

nrNumber of refinements
C++ Type:unsigned int
Range:nr >= 0
Controllable:No
Description:Number of refinements
radiusSphere (ball) radius
C++ Type:double
Unit:(no unit assumed)
Range:radius > 0.0
Controllable:No
Description:Sphere (ball) radius

Required Parameters

elem_typeThe type of element to generate
C++ Type:MooseEnum
Options:EDGE, EDGE2, EDGE3, EDGE4, QUAD, QUAD4, QUAD8, QUAD9, TRI3, TRI6, HEX, HEX8, HEX20, HEX27, TET4, TET10, PRISM6, PRISM15, PRISM18, PYRAMID5, PYRAMID13, PYRAMID14
Controllable:No
Description:The type of element to generate
n_smooth0Number of smoothing operations
Default:0
C++ Type:unsigned int
Controllable:No
Description:Number of smoothing operations

Optional Parameters

enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Controllable:No
Description:Set the enabled status of the MooseObject.
save_with_nameKeep the mesh from this mesh generator in memory with the name specified
C++ Type:std::string
Controllable:No
Description:Keep the mesh from this mesh generator in memory with the name specified

Advanced Parameters

nemesisFalseWhether or not to output the mesh file in the nemesisformat (only if output = true)
Default:False
C++ Type:bool
Controllable:No
Description:Whether or not to output the mesh file in the nemesisformat (only if output = true)
outputFalseWhether or not to output the mesh file after generating the mesh
Default:False
C++ Type:bool
Controllable:No
Description:Whether or not to output the mesh file after generating the mesh
show_infoFalseWhether or not to show mesh info after generating the mesh (bounding box, element types, sidesets, nodesets, subdomains, etc)
Default:False
C++ Type:bool
Controllable:No
Description:Whether or not to show mesh info after generating the mesh (bounding box, element types, sidesets, nodesets, subdomains, etc)

Debugging Parameters

Input Files

(test/tests/meshgenerators/sphere_mesh_generator/sphere_quad.i)
(test/tests/meshgenerators/surface_subdomains_from_all_normals/test_two_parts.i)
(test/tests/meshgenerators/sphere_mesh_generator/smooth.i)
(test/tests/meshgenerators/sphere_mesh_generator/flat.i)
(test/tests/meshgenerators/rbb_mapping_converter/circle_rbb.i)
(test/tests/meshgenerators/surface_subdomains_from_all_normals/test_flipped.i)
(test/tests/meshgenerators/surface_subdomains_delaunay_remesher/remesh_sphere.i)
(test/tests/meshgenerators/surface_subdomains_from_all_normals/test_flood.i)
(modules/heat_transfer/test/tests/directional_flux_bc/3d.i)
(tutorials/shield_multiphysics/inputs/step11_multiapps/step11_local.i)
(test/tests/misc/ad_curvature/test.i)
(test/tests/meshgenerators/surface_subdomains_from_all_normals/test_fixed.i)
(test/tests/meshgenerators/boundary_2d_delaunay_generator/sphere.i)
(test/tests/meshgenerators/sphere_mesh_generator/sphere.i)
(test/tests/meshgenerators/sphere_mesh_generator/sphere_hex27.i)

(test/tests/meshgenerators/surface_subdomains_from_all_normals/test_two_parts.i)

[Mesh]
  [sphere_vol]
    type = SphereMeshGenerator
    nr = 1
    radius = 2
  []
  [sphere_surf_sub]
    type = LowerDBlockFromSidesetGenerator
    input = 'sphere_vol'
    sidesets = '0'
    new_block_name = 'sphere_surf'
  []
  [sphere_surf_mesh]
    type = BlockToMeshConverterGenerator
    input = 'sphere_surf_sub'
    target_blocks = 'sphere_surf'
  []
  [two_spheres]
    type = CombinerGenerator
    inputs = 'sphere_surf_mesh'
    positions = '0 0 0
                 2 0 0'
  []
  [assign_subdomains]
    type = SurfaceSubdomainsFromAllNormalsGenerator
    input = 'two_spheres'
    # loose enough to paint over each coarse sphere
    normal_tol = 0.45
    contiguous_assignments_only = true
    # no need to paint over each sphere 24 times
    flood_elements_once = true
  []

  # The ordering of the elements matters for the flooding/painting loops
  allow_renumbering = false
[]

(test/tests/meshgenerators/rbb_mapping_converter/circle_rbb.i)

[Mesh]
  [sphere]
    type = SphereMeshGenerator
    radius = 1.0
    nr = 0
    elem_type = QUAD9
  []
  [rbb]
    type = RBBMappingConverter
    input = sphere
  []
[]

[Executioner]
  type = Steady
  [Quadrature]
    # Manual quadrature order, or we default to 0 with no variables and
    # our VolumePostprocessor is stuck with that
    order = FIFTH
  []
[]

[Postprocessors]
  [volume]
    type = VolumePostprocessor
  []
[]

[Problem]
  solve = false
[]

[Outputs]
  [output]
    type = CSV
  []
[]

(test/tests/meshgenerators/surface_subdomains_from_all_normals/test_flipped.i)

[Mesh]
  [sphere_vol]
    type = SphereMeshGenerator
    nr = 1
    radius = 2
  []
  [sphere_surf_sub]
    type = LowerDBlockFromSidesetGenerator
    input = 'sphere_vol'
    sidesets = '0'
    new_block_name = 'sphere_surf'
  []
  [sphere_surf_mesh]
    type = BlockToMeshConverterGenerator
    input = 'sphere_surf_sub'
    target_blocks = 'sphere_surf'
  []
  [assign_a_subdomain_at_top]
    type = SurfaceSubdomainsFromAllNormalsGenerator
    input = 'sphere_surf_mesh'
    normal_tol = 0.3
    normal = '0 0 -1'
    # otherwise we will start painting and the 'normal' is only used
    # to select the starting elements for painting
    fixed_normal = true
    show_info = true
  []
  [flip_these_elements]
    type = OrientSurfaceMeshGenerator
    input = 'assign_a_subdomain_at_top'
    included_subdomains = '2'
    normal_to_align_with = '0 0 1'
  []
  [repaint_over_ignoring_flips]
    type = SurfaceSubdomainsFromAllNormalsGenerator
    input = 'flip_these_elements'
    # large enough to paint over the entire sphere, from wherever we start
    normal_tol = 0.45
    # no need to paint elements multiple times
    flood_elements_once = true
    # ignore the orientation flips
    consider_flipped_normals = true
    flipped_normal_tol = 0.45
    # flip the elements too (not required, but can help downstream generators)
    flip_inverted_normals = true
  []

  # The ordering of the elements matters for the flooding/painting loops
  allow_renumbering = false
[]

(test/tests/meshgenerators/surface_subdomains_delaunay_remesher/remesh_sphere.i)

[Mesh]
  # Create a base sphere surface mesh
  [sphere_vol]
    type = SphereMeshGenerator
    nr = 1
    radius = 2
  []
  [sphere_surf_sub]
    type = LowerDBlockFromSidesetGenerator
    input = 'sphere_vol'
    sidesets = '0'
    new_block_name = 'sphere_surf'
  []
  [sphere_surf_mesh]
    type = BlockToMeshConverterGenerator
    input = 'sphere_surf_sub'
    target_blocks = 'sphere_surf'
  []

  # Divide it up in patches that can be flattened
  [create_patches]
    type = SurfaceSubdomainsFromAllNormalsGenerator
    input = 'sphere_surf_mesh'
    normal_tol = 0.3
    # so we limit the size of the patches to a certain angle range
    fixed_normal = true
    # no need to paint the sphere multiple times
    flood_elements_once = true
  []

  # Remesh the patches using triangle elements
  [remesh]
    type = SurfaceSubdomainsDelaunayRemesher
    input = 'create_patches'
    # keep the subdomains in this test
    avoid_merging_subdomains = true

    verbose = true
  []

  # Diagnostics
  [diag]
    type = MeshDiagnosticsGenerator
    input = remesh
    examine_element_overlap = WARNING
    examine_element_types = WARNING
    examine_element_volumes = WARNING
    examine_non_conformality = WARNING
    examine_nonplanar_sides = INFO
    examine_sidesets_orientation = WARNING
    search_for_adaptivity_nonconformality = WARNING
    check_local_jacobian = WARNING
  []

  # The ordering of the elements matters for the flooding/painting loops
  allow_renumbering = false
[]

(test/tests/meshgenerators/surface_subdomains_from_all_normals/test_flood.i)

[Mesh]
  [sphere_vol]
    type = SphereMeshGenerator
    nr = 1
    radius = 2
  []
  [sphere_surf_sub]
    type = LowerDBlockFromSidesetGenerator
    input = 'sphere_vol'
    sidesets = '0'
    new_block_name = 'sphere_surf'
  []
  [sphere_surf_mesh]
    type = BlockToMeshConverterGenerator
    input = 'sphere_surf_sub'
    target_blocks = 'sphere_surf'
  []
  [assign_subdomains_in_patches]
    type = SurfaceSubdomainsFromAllNormalsGenerator
    input = 'sphere_surf_mesh'
    normal_tol = 0.5
    # makes a couple subdomains. Note that we 'painting' over the same
    # elements multiple times because 'flood_elements_once' is not set to true
    max_subdomain_size_centroids = 1.818
  []

  # The ordering of the elements matters for the flooding/painting loops
  allow_renumbering = false
[]

(modules/heat_transfer/test/tests/directional_flux_bc/3d.i)

[Mesh]
  [planet]
    type = SphereMeshGenerator
    radius = 1
    nr = 2 # increase for a better visualization
  []

  [moon]
    type = SphereMeshGenerator
    radius = 0.3
    nr = 1 # increase for a better visualization
  []
  [combine]
    type = CombinerGenerator
    inputs = 'planet moon'
    positions = '0 0 0 -1.2 -1 -1'
  []
[]

[GlobalParams]
  illumination_flux = '1 1 1'
[]

[Variables]
  [u]
  []
  [v]
  []
[]

[Kernels]
  [diff_u]
    type = Diffusion
    variable = u
  []
  [dt_u]
    type = TimeDerivative
    variable = u
  []

  [diff_v]
    type = Diffusion
    variable = v
  []
  [dt_v]
    type = TimeDerivative
    variable = v
  []
[]

[BCs]
  [flux_u]
    type = DirectionalFluxBC
    variable = u
    boundary = 0
  []

  [flux_v]
    type = DirectionalFluxBC
    variable = v
    boundary = 0
    self_shadow_uo = shadow
  []
[]

[Postprocessors]
  [ave_v_all]
    type = SideAverageValue
    variable = v
    boundary = 0
  []
  [ave_v_exposed]
    type = ExposedSideAverageValue
    variable = v
    boundary = 0
    self_shadow_uo = shadow
  []
[]

[UserObjects]
  [shadow]
    type = SelfShadowSideUserObject
    boundary = 0
    execute_on = INITIAL
  []
[]

[Executioner]
  type = Transient
  dt = 0.1
  num_steps = 1
[]

[Outputs]
  [out]
    type = Exodus
    execute_on = FINAL
  []
[]

(tutorials/shield_multiphysics/inputs/step11_multiapps/step11_local.i)

[Mesh]
  # We make a 3D sphere, but really this could be done in 1D
  [sphere]
    type = SphereMeshGenerator
    radius = 10
    nr = 3
    n_smooth = 10
  []
  # Dimensions of each layer are not realistic
  [HDPE_inner]
    type = ParsedSubdomainMeshGenerator
    input = 'sphere'
    combinatorial_geometry = 'x*x + y*y + z*z < 2*2'
    block_id = 1
  []
  [boron_inner]
    type = ParsedSubdomainMeshGenerator
    input = 'HDPE_inner'
    combinatorial_geometry = '(x*x + y*y + z*z > 2*2) & (x*x + y*y + z*z < 3*3)'
    block_id = 2
  []
  [HDPE_mid]
    type = ParsedSubdomainMeshGenerator
    input = 'boron_inner'
    combinatorial_geometry = '(x*x + y*y + z*z > 3*3) & (x*x + y*y + z*z < 6*6)'
    block_id = 3
  []
  [boron_mid]
    type = ParsedSubdomainMeshGenerator
    input = 'HDPE_mid'
    combinatorial_geometry = '(x*x + y*y + z*z > 6*6) & (x*x + y*y + z*z < 7*7)'
    block_id = 4
  []
  [HDPE_outer]
    type = ParsedSubdomainMeshGenerator
    input = 'boron_mid'
    combinatorial_geometry = 'x*x + y*y + z*z > 7*7'
    block_id = 5
  []
  [rename]
    type = RenameBlockGenerator
    input = 'HDPE_outer'
    old_block = '1 2 3 4 5'
    new_block = 'HDPE_inner boron_inner HDPE_mid boron_mid HDPE_outer'
  []
  [rename_boundary]
    type = RenameBoundaryGenerator
    input = 'rename'
    old_boundary = '0'
    new_boundary = 'outer'
  []

  # length_unit = 0.01
  [scale]
    type = TransformGenerator
    input = rename_boundary
    transform = SCALE
    vector_value = '0.01 0.01 0.01'
  []
[]

[Variables]
  [T]
    initial_condition = 300
  []
[]

# Solve heat equation, with a source from boron absorption
[Kernels]
  [conduction]
    type = HeatConduction
    variable = T
  []
  [source]
    type = CoupledForce
    variable = T
    block = 'boron_inner boron_mid'
    v = flux
    # 2 is our arbitrary value for the group cross section
    coef = 2
  []
[]

[BCs]
  [outer]
    type = PostprocessorDirichletBC
    boundary = 'outer'
    variable = 'T'
    postprocessor = 'T_boundary'
  []
[]

[AuxVariables]
  # Received from the main solve
  [flux]
    initial_condition = 1e5
  []
[]

[Materials]
  [hdpe]
    type = HeatConductionMaterial
    block = 'HDPE_inner HDPE_mid HDPE_outer'
    # arbitrary
    thermal_conductivity = 10
  []
  [boron]
    type = HeatConductionMaterial
    block = 'boron_inner boron_mid'
    # arbitrary
    thermal_conductivity = 7
  []
[]

[Executioner]
  type = Steady
  solve_type = NEWTON
  petsc_options_iname = '-pc_type -pc_hypre_type'
  petsc_options_value = 'hypre boomeramg'
[]

[Postprocessors]
  # Used for boundary condition, received from the main solve
  [T_boundary]
    type = Receiver
    default = 320
  []

  # Compute those then send to the main app
  [T_hdpe_out]
    type = ElementAverageValue
    variable = 'T'
    block = 'HDPE_outer'
  []
  [T_boron_mid]
    type = ElementAverageValue
    variable = 'T'
    block = 'boron_mid'
  []
  [T_hdpe_mid]
    type = ElementAverageValue
    variable = 'T'
    block = 'HDPE_mid'
  []
  [T_boron_inner]
    type = ElementAverageValue
    variable = 'T'
    block = 'boron_inner'
  []
  [T_hdpe_inner]
    type = ElementAverageValue
    variable = 'T'
    block = 'HDPE_inner'
  []
[]

[Outputs]
  exodus = true
[]

(test/tests/misc/ad_curvature/test.i)

[Mesh]
  [sphere]
    type = SphereMeshGenerator
    radius = 1
    nr = 1
    elem_type = HEX27
  []
[]

[Problem]
  solve = false
[]

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

[AuxKernels]
  [curvature]
    variable = curvature
    type = ADCurvatureAux
    execute_on = 'initial'
    boundary = 0
  []
[]

[Executioner]
  type = Steady
[]

[Outputs]
  csv = true
[]

[Postprocessors]
  [average]
    type = SideAverageValue
    execute_on = 'initial'
    variable = curvature
    boundary = 0
  []
[]

(test/tests/meshgenerators/surface_subdomains_from_all_normals/test_fixed.i)

[Mesh]
  [sphere_vol]
    type = SphereMeshGenerator
    nr = 1
    radius = 2
  []
  [sphere_surf_sub]
    type = LowerDBlockFromSidesetGenerator
    input = 'sphere_vol'
    sidesets = '0'
    new_block_name = 'sphere_surf'
  []
  [sphere_surf_mesh]
    type = BlockToMeshConverterGenerator
    input = 'sphere_surf_sub'
    target_blocks = 'sphere_surf'
  []
  [assign_a_subdomain_at_top]
    type = SurfaceSubdomainsFromAllNormalsGenerator
    input = 'sphere_surf_mesh'
    normal_tol = 0.3
    normal = '0 0 -1'
    # otherwise we will start painting and the 'normal' is only used
    # to select the starting elements for painting
    fixed_normal = true
  []

  # The ordering of the elements matters for the flooding/painting loops
  allow_renumbering = false
[]

(test/tests/meshgenerators/boundary_2d_delaunay_generator/sphere.i)

[Mesh]
  [sphere]
    type = SphereMeshGenerator
    nr = 2
    radius = 1
  []
  [bdry]
    type = ParsedGenerateSideset
    combinatorial_geometry = 'z>0.5'
    new_sideset_name = 'bdry'
    input = 'sphere'
    included_boundaries = '0'
  []
  [hole]
    type = ParsedGenerateSideset
    combinatorial_geometry = 'z>0.8'
    new_sideset_name = 'hole'
    input = 'bdry'
    included_boundaries = '0'
  []
  [b2dd]
    type = Boundary2DDelaunayGenerator
    input = hole
    boundary_names = 'bdry'
    hole_boundary_names = 'hole'
    use_auto_area_func = true
  []
[]

[Problem]
  solve = false
[]

[Executioner]
  type = Transient
  num_steps = 1
[]

[Postprocessors]
  [area]
    type = VolumePostprocessor
  []
[]

[Outputs]
  [csv]
    type = CSV
    execute_on = 'FINAL'
  []
[]

Overview
Input Parameters
Input Files