FreeCAD/src/Mod/Fem/FemMeshTools.py

939 lines
45 KiB
Python

# ***************************************************************************
# * *
# * Copyright (c) 2016 - Bernd Hahnebach <bernd@bimstatik.org> *
# * *
# * This program is free software; you can redistribute it and/or modify *
# * it under the terms of the GNU Lesser General Public License (LGPL) *
# * as published by the Free Software Foundation; either version 2 of *
# * the License, or (at your option) any later version. *
# * for detail see the LICENCE text file. *
# * *
# * This program is distributed in the hope that it will be useful, *
# * but WITHOUT ANY WARRANTY; without even the implied warranty of *
# * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
# * GNU Library General Public License for more details. *
# * *
# * You should have received a copy of the GNU Library General Public *
# * License along with this program; if not, write to the Free Software *
# * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 *
# * USA *
# * *
# ***************************************************************************
__title__ = "Tools for the work with FEM meshes"
__author__ = "Bernd Hahnebach"
__url__ = "http://www.freecadweb.org"
import FreeCAD
def get_femelements_by_references(femmesh, femelement_table, references):
'''get the femelements for a list of references
'''
references_femelements = []
for ref in references:
ref_femnodes = get_femnodes_by_refshape(femmesh, ref) # femnodes for the current ref
references_femelements += get_femelements_by_femnodes(femelement_table, ref_femnodes) # femelements for all references
return references_femelements
def get_femnodes_by_references(femmesh, references):
'''get the femnodes for a list of references
'''
references_femnodes = []
for ref in references:
references_femnodes += get_femnodes_by_refshape(femmesh, ref)
# return references_femnodes # keeps duplicate nodes, keeps node order
# if nodes are used for nodesets, duplicats should be removed
return list(set(references_femnodes)) # removes duplicate nodes, sortes node order
def get_femnodes_by_refshape(femmesh, ref):
nodes = []
for refelement in ref[1]:
if refelement:
r = ref[0].Shape.getElement(refelement) # Vertex, Edge, Face
else:
r = ref[0].Shape # solid
print(' ReferenceShape : ', r.ShapeType, ', ', ref[0].Name, ', ', ref[0].Label, ' --> ', refelement)
if r.ShapeType == 'Vertex':
nodes += femmesh.getNodesByVertex(r)
elif r.ShapeType == 'Edge':
nodes += femmesh.getNodesByEdge(r)
elif r.ShapeType == 'Face':
nodes += femmesh.getNodesByFace(r)
elif r.ShapeType == 'Solid':
nodes += femmesh.getNodesBySolid(r)
else:
print(' No Vertice, Edge, Face or Solid as reference shapes!')
return nodes
def get_femelement_table(femmesh):
""" get_femelement_table(femmesh): { elementid : [ nodeid, nodeid, ... , nodeid ] }"""
femelement_table = {}
if is_solid_femmesh(femmesh):
for i in femmesh.Volumes:
femelement_table[i] = femmesh.getElementNodes(i)
elif is_face_femmesh(femmesh):
for i in femmesh.Faces:
femelement_table[i] = femmesh.getElementNodes(i)
elif is_edge_femmesh(femmesh):
for i in femmesh.Edges:
femelement_table[i] = femmesh.getElementNodes(i)
else:
FreeCAD.Console.PrintError('Neither solid nor face nor edge femmesh!\n')
return femelement_table
def get_femelements_by_femnodes(femelement_table, node_list):
'''for every femelement of femelement_table
if all nodes of the femelement are in node_list,
the femelement is added to the list which is returned
e: elementlist
nodes: nodelist '''
e = [] # elementlist
for elementID in sorted(femelement_table):
nodecount = 0
for nodeID in femelement_table[elementID]:
if nodeID in node_list:
nodecount = nodecount + 1
if nodecount == len(femelement_table[elementID]): # all nodes of the element are in the node_list!
e.append(elementID)
return e
def get_femvolumeelements_by_femfacenodes(femelement_table, node_list):
'''assume femelement_table only has volume elements
for every femvolumeelement of femelement_table
for tetra4 and tetra10 the C++ methods could be used --> test again to be sure
if hexa8 volume element --> if exact 4 element nodes are in node_list --> add femelement
if hexa20 volume element --> if exact 8 element nodes are in node_list --> add femelement
if penta6 volume element --> if exact 3 or 6 element nodes are in node_list --> add femelement
if penta15 volume element --> if exact 6 or 8 element nodes are in node_list --> add femelement
e: elementlist
nodes: nodelist '''
e = [] # elementlist
for elementID in sorted(femelement_table):
nodecount = 0
el_nd_ct = len(femelement_table[elementID])
if el_nd_ct == 8: # hexa8
for nodeID in femelement_table[elementID]:
if nodeID in node_list:
nodecount = nodecount + 1
if nodecount == 4:
e.append(elementID)
elif el_nd_ct == 20: # hexa20
for nodeID in femelement_table[elementID]:
if nodeID in node_list:
nodecount = nodecount + 1
if nodecount == 8:
e.append(elementID)
elif el_nd_ct == 6: # penta6
for nodeID in femelement_table[elementID]:
if nodeID in node_list:
nodecount = nodecount + 1
if nodecount == 3 or nodecount == 4:
e.append(elementID)
elif el_nd_ct == 15: # penta15
for nodeID in femelement_table[elementID]:
if nodeID in node_list:
nodecount = nodecount + 1
if nodecount == 6 or nodecount == 8:
e.append(elementID)
else:
FreeCAD.Console.PrintError('Error in get_femvolumeelements_by_femfacenodes(): not known volume element: ' + el_nd_ct + '\n')
# print sorted(e)
return e
def get_femelement_sets(femmesh, femelement_table, fem_objects): # fem_objects = FreeCAD FEM document objects
# get femelements for reference shapes of each obj.References
count_femelements = 0
referenced_femelements = []
has_remaining_femelements = None
for fem_object_i, fem_object in enumerate(fem_objects):
obj = fem_object['Object']
fem_object['ShortName'] = get_elset_short_name(obj, fem_object_i) # unique short identifier
if obj.References:
ref_shape_femelements = []
ref_shape_femelements = get_femelements_by_references(femmesh, femelement_table, obj.References)
referenced_femelements += ref_shape_femelements
count_femelements += len(ref_shape_femelements)
fem_object['FEMElements'] = ref_shape_femelements
else:
has_remaining_femelements = obj.Name
# get remaining femelements for the fem_objects
if has_remaining_femelements:
remaining_femelements = []
for elemid in femelement_table:
if elemid not in referenced_femelements:
remaining_femelements.append(elemid)
count_femelements += len(remaining_femelements)
for fem_object in fem_objects:
obj = fem_object['Object']
if obj.Name == has_remaining_femelements:
fem_object['FEMElements'] = sorted(remaining_femelements)
# check if all worked out well
if not femelements_count_ok(femelement_table, count_femelements):
FreeCAD.Console.PrintError('Error in get_femelement_sets -- > femelements_count_ok() failed!\n')
def get_elset_short_name(obj, i):
if hasattr(obj, "Proxy") and obj.Proxy.Type == 'MechanicalMaterial':
return 'Mat' + str(i)
elif hasattr(obj, "Proxy") and obj.Proxy.Type == 'FemBeamSection':
return 'Beam' + str(i)
elif hasattr(obj, "Proxy") and obj.Proxy.Type == 'FemShellThickness':
return 'Shell' + str(i)
else:
print('Error: ', obj.Name, ' --> ', obj.Proxy.Type)
def get_force_obj_vertex_nodeload_table(femmesh, frc_obj):
# force_obj_node_load_table = [('refshape_name.elemname',node_load_table), ..., ('refshape_name.elemname',node_load_table)]
force_obj_node_load_table = []
node_load = frc_obj.Force / len(frc_obj.References)
for o, elem_tup in frc_obj.References:
node_count = len(elem_tup)
for elem in elem_tup:
ref_node = o.Shape.getElement(elem)
node = femmesh.getNodesByVertex(ref_node)
elem_info_string = 'node load on shape: ' + o.Name + ':' + elem
force_obj_node_load_table.append((elem_info_string, {node[0]: node_load / node_count}))
return force_obj_node_load_table
def get_force_obj_edge_nodeload_table(femmesh, femelement_table, femnodes_mesh, frc_obj):
# force_obj_node_load_table = [('refshape_name.elemname',node_load_table), ..., ('refshape_name.elemname',node_load_table)]
force_obj_node_load_table = []
sum_ref_edge_length = 0
sum_ref_edge_node_length = 0 # for debugging
sum_node_load = 0 # for debugging
for o, elem_tup in frc_obj.References:
for elem in elem_tup:
sum_ref_edge_length += o.Shape.getElement(elem).Length
if sum_ref_edge_length != 0:
force_per_sum_ref_edge_length = frc_obj.Force / sum_ref_edge_length
for o, elem_tup in frc_obj.References:
for elem in elem_tup:
ref_edge = o.Shape.getElement(elem)
# edge_table = { meshedgeID : ( nodeID, ... , nodeID ) }
edge_table = get_ref_edgenodes_table(femmesh, femelement_table, ref_edge)
# node_length_table = [ (nodeID, length), ... , (nodeID, length) ] some nodes will have more than one entry
node_length_table = get_ref_edgenodes_lengths(femnodes_mesh, edge_table)
# node_sum_length_table = { nodeID : Length, ... , nodeID : Length } LengthSum for each node, one entry for each node
node_sum_length_table = get_ref_shape_node_sum_geom_table(node_length_table)
# node_load_table = { nodeID : NodeLoad, ... , nodeID : NodeLoad } NodeLoad for each node, one entry for each node
node_load_table = {}
sum_node_lengths = 0 # for debugging
for node in node_sum_length_table:
sum_node_lengths += node_sum_length_table[node] # for debugging
node_load_table[node] = node_sum_length_table[node] * force_per_sum_ref_edge_length
ratio_refedge_lengths = sum_node_lengths / ref_edge.Length
if ratio_refedge_lengths < 0.99 or ratio_refedge_lengths > 1.01:
FreeCAD.Console.PrintError('Error on: ' + frc_obj.Name + ' --> ' + o.Name + '.' + elem + '\n')
print(' sum_node_lengths:', sum_node_lengths)
print(' refedge_length: ', ref_edge.Length)
bad_refedge = ref_edge
sum_ref_edge_node_length += sum_node_lengths
elem_info_string = 'node loads on shape: ' + o.Name + ':' + elem
force_obj_node_load_table.append((elem_info_string, node_load_table))
for ref_shape in force_obj_node_load_table:
for node in ref_shape[1]:
sum_node_load += ref_shape[1][node] # for debugging
ratio = sum_node_load / frc_obj.Force
if ratio < 0.99 or ratio > 1.01:
print('Deviation sum_node_load to frc_obj.Force is more than 1% : ', ratio)
print(' sum_ref_edge_node_length: ', sum_ref_edge_node_length)
print(' sum_ref_edge_length: ', sum_ref_edge_length)
print(' sum_node_load: ', sum_node_load)
print(' frc_obj.Force: ', frc_obj.Force)
print(' the reason could be simply a circle length --> see method get_ref_edge_node_lengths')
print(' the reason could also be an problem in retrieving the ref_edge_node_length')
# try debugging of the last bad refedge
print('DEBUGGING')
print(bad_refedge)
print('bad_refedge_nodes')
bad_refedge_nodes = femmesh.getNodesByEdge(bad_refedge)
print(len(bad_refedge_nodes))
print(bad_refedge_nodes)
# import FreeCADGui
# FreeCADGui.ActiveDocument.Compound_Mesh.HighlightedNodes = bad_refedge_nodes
print('bad_edge_table')
# bad_edge_table = { meshedgeID : ( nodeID, ... , nodeID ) }
bad_edge_table = get_ref_edgenodes_table(femmesh, femelement_table, bad_refedge)
print(len(bad_edge_table))
bad_edge_table_nodes = []
for elem in bad_edge_table:
print(elem, ' --> ', bad_edge_table[elem])
for node in bad_edge_table[elem]:
if node not in bad_edge_table_nodes:
bad_edge_table_nodes.append(node)
print('sorted(bad_edge_table_nodes)')
print(sorted(bad_edge_table_nodes)) # should be == bad_refedge_nodes
# import FreeCADGui
# FreeCADGui.ActiveDocument.Compound_Mesh.HighlightedNodes = bad_edge_table_nodes
# bad_node_length_table = [ (nodeID, length), ... , (nodeID, length) ] some nodes will have more than one entry
print('good_edge_table')
good_edge_table = delete_duplicate_mesh_elements(bad_edge_table)
for elem in good_edge_table:
print(elem, ' --> ', bad_edge_table[elem])
print('bad_node_length_table')
bad_node_length_table = get_ref_edgenodes_lengths(femnodes_mesh, bad_edge_table)
for n, l in bad_node_length_table:
print(n, ' --> ', l)
return force_obj_node_load_table
def get_force_obj_face_nodeload_table(femmesh, femelement_table, femnodes_mesh, frc_obj):
# force_obj_node_load_table = [('refshape_name.elemname',node_load_table), ..., ('refshape_name.elemname',node_load_table)]
force_obj_node_load_table = []
sum_ref_face_area = 0
sum_ref_face_node_area = 0 # for debugging
sum_node_load = 0 # for debugging
for o, elem_tup in frc_obj.References:
for elem in elem_tup:
sum_ref_face_area += o.Shape.getElement(elem).Area
if sum_ref_face_area != 0:
force_per_sum_ref_face_area = frc_obj.Force / sum_ref_face_area
for o, elem_tup in frc_obj.References:
for elem in elem_tup:
ref_face = o.Shape.getElement(elem)
# face_table = { meshfaceID : ( nodeID, ... , nodeID ) }
face_table = get_ref_facenodes_table(femmesh, femelement_table, ref_face)
# node_area_table = [ (nodeID, Area), ... , (nodeID, Area) ] some nodes will have more than one entry
node_area_table = get_ref_facenodes_areas(femnodes_mesh, face_table)
# node_sum_area_table = { nodeID : Area, ... , nodeID : Area } AreaSum for each node, one entry for each node
node_sum_area_table = get_ref_shape_node_sum_geom_table(node_area_table)
# node_load_table = { nodeID : NodeLoad, ... , nodeID : NodeLoad } NodeLoad for each node, one entry for each node
node_load_table = {}
sum_node_areas = 0 # for debugging
for node in node_sum_area_table:
sum_node_areas += node_sum_area_table[node] # for debugging
node_load_table[node] = node_sum_area_table[node] * force_per_sum_ref_face_area
ratio_refface_areas = sum_node_areas / ref_face.Area
if ratio_refface_areas < 0.99 or ratio_refface_areas > 1.01:
FreeCAD.Console.PrintError('Error on: ' + frc_obj.Name + ' --> ' + o.Name + '.' + elem + '\n')
print(' sum_node_areas:', sum_node_areas)
print(' ref_face_area: ', ref_face.Area)
sum_ref_face_node_area += sum_node_areas
elem_info_string = 'node loads on shape: ' + o.Name + ':' + elem
force_obj_node_load_table.append((elem_info_string, node_load_table))
for ref_shape in force_obj_node_load_table:
for node in ref_shape[1]:
sum_node_load += ref_shape[1][node] # for debugging
ratio = sum_node_load / frc_obj.Force
if ratio < 0.99 or ratio > 1.01:
print('Deviation sum_node_load to frc_obj.Force is more than 1% : ', ratio)
print(' sum_ref_face_node_area: ', sum_ref_face_node_area)
print(' sum_ref_face_area: ', sum_ref_face_area)
print(' sum_node_load: ', sum_node_load)
print(' frc_obj.Force: ', frc_obj.Force)
print(' the reason could be simply a circle area --> see method get_ref_face_node_areas')
print(' the reason could also be an problem in retrieving the ref_face_node_area')
return force_obj_node_load_table
def get_ref_edgenodes_table(femmesh, femelement_table, refedge):
edge_table = {} # { meshedgeID : ( nodeID, ... , nodeID ) }
refedge_nodes = femmesh.getNodesByEdge(refedge)
if is_solid_femmesh(femmesh):
refedge_fem_volumeelements = []
# if at least two nodes of a femvolumeelement are in refedge_nodes the volume is added to refedge_fem_volumeelements
for elem in femelement_table:
nodecount = 0
for node in femelement_table[elem]:
if node in refedge_nodes:
nodecount += 1
if nodecount > 1:
refedge_fem_volumeelements.append(elem)
# for every refedge_fem_volumeelement look which of his nodes is in refedge_nodes --> add all these nodes to edge_table
for elem in refedge_fem_volumeelements:
fe_refedge_nodes = []
for node in femelement_table[elem]:
if node in refedge_nodes:
fe_refedge_nodes.append(node)
edge_table[elem] = fe_refedge_nodes # { volumeID : ( edgenodeID, ... , edgenodeID )} # only the refedge nodes
# FIXME duplicate_mesh_elements: as soon as contact ans springs are supported the user should decide on which edge the load is applied
edge_table = delete_duplicate_mesh_elements(edge_table)
elif is_face_femmesh(femmesh):
refedge_fem_faceelements = []
# if at least two nodes of a femfaceelement are in refedge_nodes the volume is added to refedge_fem_volumeelements
for elem in femelement_table:
nodecount = 0
for node in femelement_table[elem]:
if node in refedge_nodes:
nodecount += 1
if nodecount > 1:
refedge_fem_faceelements.append(elem)
# for every refedge_fem_faceelement look which of his nodes is in refedge_nodes --> add all these nodes to edge_table
for elem in refedge_fem_faceelements:
fe_refedge_nodes = []
for node in femelement_table[elem]:
if node in refedge_nodes:
fe_refedge_nodes.append(node)
edge_table[elem] = fe_refedge_nodes # { faceID : ( edgenodeID, ... , edgenodeID )} # only the refedge nodes
# FIXME duplicate_mesh_elements: as soon as contact ans springs are supported the user should decide on which edge the load is applied
edge_table = delete_duplicate_mesh_elements(edge_table)
elif is_edge_femmesh(femmesh):
refedge_fem_edgeelements = get_femelements_by_femnodes(femelement_table, refedge_nodes)
for elem in refedge_fem_edgeelements:
edge_table[elem] = femelement_table[elem] # { edgeID : ( nodeID, ... , nodeID )} # all nodes off this femedgeelement
return edge_table
def get_ref_edgenodes_lengths(femnodes_mesh, edge_table):
# calulate the appropriate node_length for every node of every mesh edge (me)
# G. Lakshmi Narasaiah, Finite Element Analysis, p206ff
# [ (nodeID, length), ... , (nodeID, length) ] some nodes will have more than one entry
if (not femnodes_mesh) or (not edge_table):
FreeCAD.Console.PrintError("Error in get_ref_edgenodes_lengths(): Empty femnodes_mesh or edge_table!\n")
return []
node_length_table = []
mesh_edge_length = 0
# print(len(edge_table))
for me in edge_table:
femmesh_edgetype = len(edge_table[me])
if femmesh_edgetype == 2: # 2 node femmesh edge
# end_node_length = mesh_edge_length / 2
# ______
# P1 P2
P1 = femnodes_mesh[edge_table[me][0]]
P2 = femnodes_mesh[edge_table[me][1]]
edge_vec = P2 - P1
mesh_edge_length = edge_vec.Length
# print(mesh_edge_length)
end_node_length = mesh_edge_length / 2.0
node_length_table.append((edge_table[me][0], end_node_length))
node_length_table.append((edge_table[me][1], end_node_length))
elif femmesh_edgetype == 3: # 3 node femmesh edge
# end_node_length = mesh_edge_length / 6
# middle_node_length = mesh_face_area * 2 / 3
# _______ _______
# P1 P3 P2
P1 = femnodes_mesh[edge_table[me][0]]
P2 = femnodes_mesh[edge_table[me][1]]
P3 = femnodes_mesh[edge_table[me][2]]
edge_vec1 = P3 - P1
edge_vec2 = P2 - P3
mesh_edge_length = edge_vec1.Length + edge_vec2.Length
# print(me, ' --> ', mesh_edge_length)
end_node_length = mesh_edge_length / 6.0
middle_node_length = mesh_edge_length * 2.0 / 3.0
node_length_table.append((edge_table[me][0], end_node_length))
node_length_table.append((edge_table[me][1], end_node_length))
node_length_table.append((edge_table[me][2], middle_node_length))
return node_length_table
def get_ref_facenodes_table(femmesh, femelement_table, ref_face):
face_table = {} # { meshfaceID : ( nodeID, ... , nodeID ) }
if is_solid_femmesh(femmesh):
if has_no_face_data(femmesh):
print('No face date in volume mesh. We try to use getccxVolumesByFace() to retrive the volume elments of the ref_face!')
# there is no face data
# the problem if we retrive the nodes ourself is they are not sorted we just have the nodes. We need to sourt them according
# the shell mesh notaion of tria3, tria6, quad4, quad8
ref_face_nodes = femmesh.getNodesByFace(ref_face)
# try to use getccxVolumesByFace() to get the volume ids of element with elementfaces on the ref_face --> should work for tetra4 and tetra10
ref_face_volume_elements = femmesh.getccxVolumesByFace(ref_face) # list of tupels (mv, ccx_face_nr)
if ref_face_volume_elements: # mesh with tetras
print('Use of getccxVolumesByFace() has returned volume elements of the ref_face!')
for ve in ref_face_volume_elements:
veID = ve[0]
ve_ref_face_nodes = []
for nodeID in femelement_table[veID]:
if nodeID in ref_face_nodes:
ve_ref_face_nodes.append(nodeID)
face_table[veID] = ve_ref_face_nodes # { volumeID : ( facenodeID, ... , facenodeID ) } only the ref_face nodes
else: # mesh with hexa or penta
print('Use of getccxVolumesByFace() has NOT returned volume elements of the ref_face! We try to use get_femvolumeelements_by_femfacenodes()!')
ref_face_volume_elements = get_femvolumeelements_by_femfacenodes(femelement_table, ref_face_nodes) # list of integer [mv]
for veID in ref_face_volume_elements:
ve_ref_face_nodes = []
for nodeID in femelement_table[veID]:
if nodeID in ref_face_nodes:
ve_ref_face_nodes.append(nodeID)
face_table[veID] = ve_ref_face_nodes # { volumeID : ( facenodeID, ... , facenodeID ) } only the ref_face nodes
face_table = build_mesh_faces_of_volume_elements(face_table, femelement_table) # we need to resort the nodes to make them build a element face
else: # the femmesh has face_data
faces = femmesh.getFacesByFace(ref_face) # (mv, mf)
for mf in faces:
face_table[mf] = femmesh.getElementNodes(mf)
elif is_face_femmesh(femmesh):
ref_face_nodes = femmesh.getNodesByFace(ref_face)
ref_face_elements = get_femelements_by_femnodes(femelement_table, ref_face_nodes)
for mf in ref_face_elements:
face_table[mf] = femelement_table[mf]
# print face_table
return face_table
def build_mesh_faces_of_volume_elements(face_table, femelement_table):
# node index of facenodes in femelementtable volume element
# if we know the position of the node we can build the element face out of the unsorted face nodes
face_nodenumber_table = {} # { volumeID : ( index, ... , index ) }
for veID in face_table:
face_nodenumber_table[veID] = []
for n in face_table[veID]:
index = femelement_table[veID].index(n)
# print(index)
face_nodenumber_table[veID].append(index + 1) # lokale node number = index + 1
# print 'VolElement:', veID
# print ' --> ', femelement_table[veID]
# print ' --> ', face_table[veID]
# print ' --> ', face_nodenumber_table[veID]
for veID in face_nodenumber_table:
vol_node_ct = len(femelement_table[veID])
face_node_indexs = sorted(face_nodenumber_table[veID])
if vol_node_ct == 10: # tetra10 --> tria6 face
if face_node_indexs == [1, 2, 3, 5, 6, 7]: # node order of face in tetra10 volume element
node_numbers = (1, 2, 3, 5, 6, 7) # node order of a tria6 face of tetra10
elif face_node_indexs == [1, 2, 4, 5, 8, 9]:
node_numbers = (1, 4, 2, 8, 9, 5)
elif face_node_indexs == [1, 3, 4, 7, 8, 10]:
node_numbers = (1, 3, 4, 7, 10, 8)
elif face_node_indexs == [2, 3, 4, 6, 9, 10]:
node_numbers = (2, 4, 3, 9, 10, 6)
else:
FreeCAD.Console.PrintError("Error in build_mesh_faces_of_volume_elements(): hexa20: face not found!" + str(face_node_indexs) + "\n")
elif vol_node_ct == 4: # tetra4 --> tria3 face
if face_node_indexs == [1, 2, 3]: # node order of face in tetra4 volume element
node_numbers = (1, 2, 3) # node order of a tria3 face of tetra4
elif face_node_indexs == [1, 2, 4]:
node_numbers = (1, 4, 2, 8)
elif face_node_indexs == [1, 3, 4]:
node_numbers = (1, 3, 4)
elif face_node_indexs == [2, 3, 4]:
node_numbers = (2, 4, 3)
else:
FreeCAD.Console.PrintError("Error in build_mesh_faces_of_volume_elements(): hexa20: face not found!" + str(face_node_indexs) + "\n")
elif vol_node_ct == 20: # hexa20 --> quad8 face
if face_node_indexs == [1, 2, 3, 4, 9, 10, 11, 12]: # node order of face in hexa20 volume element
node_numbers = (1, 2, 3, 4, 9, 10, 11, 12) # node order of a quad8 face of hexa20
elif face_node_indexs == [5, 6, 7, 8, 13, 14, 15, 16]:
node_numbers = (5, 8, 7, 6, 16, 15, 14, 13)
elif face_node_indexs == [1, 2, 5, 6, 9, 13, 17, 18]:
node_numbers = (1, 5, 6, 2, 17, 13, 18, 9)
elif face_node_indexs == [3, 4, 7, 8, 11, 15, 19, 20]:
node_numbers = (3, 7, 8, 4, 19, 15, 20, 11)
elif face_node_indexs == [1, 4, 5, 8, 12, 16, 17, 20]:
node_numbers = (1, 4, 8, 5, 12, 20, 16, 17)
elif face_node_indexs == [2, 3, 6, 7, 10, 14, 18, 19]:
node_numbers = (2, 6, 7, 3, 18, 14, 19, 10)
else:
FreeCAD.Console.PrintError("Error in build_mesh_faces_of_volume_elements(): hexa20: face not found!" + str(face_node_indexs) + "\n")
elif vol_node_ct == 8: # hexa8 --> quad4 face
face_node_indexs = sorted(face_nodenumber_table[veID])
if face_node_indexs == [1, 2, 3, 4]: # node order of face in hexa8 volume element
node_numbers = (1, 2, 3, 4) # node order of a quad8 face of hexa8
elif face_node_indexs == [5, 6, 7, 8]:
node_numbers = (5, 8, 7, 6)
elif face_node_indexs == [1, 2, 5, 6]:
node_numbers = (1, 5, 6, 2)
elif face_node_indexs == [3, 4, 7, 8]:
node_numbers = (3, 7, 8, 4)
elif face_node_indexs == [1, 4, 5, 8]:
node_numbers = (1, 4, 8, 5)
elif face_node_indexs == [2, 3, 6, 7]:
node_numbers = (2, 6, 7, 3)
else:
FreeCAD.Console.PrintError("Error in build_mesh_faces_of_volume_elements(): hexa20: face not found!" + str(face_node_indexs) + "\n")
elif vol_node_ct == 15: # penta15 --> tria6 and quad8 faces
if face_node_indexs == [1, 2, 3, 7, 8, 9]: # node order of face in penta15 volume element
node_numbers = (1, 2, 3, 7, 8, 9) # node order of a tria6 face of penta15
elif face_node_indexs == [4, 5, 6, 10, 11, 12]:
node_numbers = (4, 6, 5, 12, 11, 10) # tria6
elif face_node_indexs == [1, 2, 4, 5, 7, 10, 13, 14]:
node_numbers = (1, 4, 5, 2, 13, 10, 14, 7) # quad8
elif face_node_indexs == [1, 3, 4, 6, 9, 12, 13, 15]:
node_numbers = (1, 3, 6, 4, 9, 15, 12, 13) # quad8
elif face_node_indexs == [2, 3, 5, 6, 8, 11, 14, 15]:
node_numbers = (2, 5, 6, 3, 14, 11, 15, 8) # quad8
else:
FreeCAD.Console.PrintError("Error in build_mesh_faces_of_volume_elements(): penta15: face not found!" + str(face_node_indexs) + "\n")
elif vol_node_ct == 6: # penta6 --> tria3 and quad4 faces
if face_node_indexs == [1, 2, 3]: # node order of face in penta6 volume element
node_numbers = (1, 2, 3) # node order of a tria3 face of penta6
elif face_node_indexs == [4, 5, 6]:
node_numbers = (4, 6, 5) # tria3
elif face_node_indexs == [1, 2, 4, 5]:
node_numbers = (1, 4, 5, 2) # quad4
elif face_node_indexs == [1, 3, 4, 6]:
node_numbers = (1, 3, 6, 4) # quad4
elif face_node_indexs == [2, 3, 5, 6]:
node_numbers = (2, 5, 6, 3) # quad4
else:
FreeCAD.Console.PrintError("Error in build_mesh_faces_of_volume_elements(): pent6: face not found!" + str(face_node_indexs) + "\n")
else:
FreeCAD.Console.PrintError("Error in build_mesh_faces_of_volume_elements(): Volume not implemented: volume node count" + str(vol_node_ct) + "\n")
face_nodes = []
for i in node_numbers:
i -= 1 # node_number starts with 1, index starts with 0 --> index = node number - 1
face_nodes.append(femelement_table[veID][i])
face_table[veID] = face_nodes # reset the entry in face_table
# print ' --> ', face_table[veID]
return face_table
def get_ref_facenodes_areas(femnodes_mesh, face_table):
# calulate the appropriate node_areas for every node of every mesh face (mf)
# G. Lakshmi Narasaiah, Finite Element Analysis, p206ff
# FIXME only gives exact results in case of a real triangle. If for S6 or C3D10 elements
# the midnodes are not on the line between the end nodes the area will not be a triangle
# see http://forum.freecadweb.org/viewtopic.php?f=18&t=10939&start=40#p91355 and ff
# same applies for the quads, results are exact only if mid nodes are on the line between corner nodes
# [ (nodeID,Area), ... , (nodeID,Area) ] some nodes will have more than one entry
if (not femnodes_mesh) or (not face_table):
FreeCAD.Console.PrintError("Error: Empty femnodes_mesh or face_table!\n")
return []
node_area_table = []
mesh_face_area = 0
for mf in face_table:
femmesh_facetype = len(face_table[mf])
# nodes in face_table need to be in the right node order for the following calcualtions
if femmesh_facetype == 3: # 3 node femmesh face triangle
# corner_node_area = mesh_face_area / 3.0
# P3
# /\
# / \
# /____\
# P1 P2
P1 = femnodes_mesh[face_table[mf][0]]
P2 = femnodes_mesh[face_table[mf][1]]
P3 = femnodes_mesh[face_table[mf][2]]
mesh_face_area = get_triangle_area(P1, P2, P3)
corner_node_area = mesh_face_area / 3.0
node_area_table.append((face_table[mf][0], corner_node_area))
node_area_table.append((face_table[mf][1], corner_node_area))
node_area_table.append((face_table[mf][2], corner_node_area))
elif femmesh_facetype == 4: # 4 node femmesh face quad
# corner_node_area = mesh_face_area / 4.0
# P4_______P3
# | /|
# | t2 / |
# | / |
# | / |
# | / t1 |
# |/_____|
# P1 P2
P1 = femnodes_mesh[face_table[mf][0]]
P2 = femnodes_mesh[face_table[mf][1]]
P3 = femnodes_mesh[face_table[mf][2]]
P4 = femnodes_mesh[face_table[mf][3]]
mesh_face_t1_area = get_triangle_area(P1, P2, P3)
mesh_face_t2_area = get_triangle_area(P1, P3, P4)
mesh_face_area = mesh_face_t1_area + mesh_face_t1_area
corner_node_area = mesh_face_area / 4.0
node_area_table.append((face_table[mf][0], corner_node_area))
node_area_table.append((face_table[mf][1], corner_node_area))
node_area_table.append((face_table[mf][2], corner_node_area))
node_area_table.append((face_table[mf][3], corner_node_area))
elif femmesh_facetype == 6: # 6 node femmesh face triangle
# corner_node_area = 0
# middle_node_area = mesh_face_area / 3.0
# P3
# /\
# /t3\
# / \
# P6------P5
# / \ t4 / \
# /t1 \ /t2 \
# /_____\/_____\
# P1 P4 P2
P1 = femnodes_mesh[face_table[mf][0]]
P2 = femnodes_mesh[face_table[mf][1]]
P3 = femnodes_mesh[face_table[mf][2]]
P4 = femnodes_mesh[face_table[mf][3]]
P5 = femnodes_mesh[face_table[mf][4]]
P6 = femnodes_mesh[face_table[mf][5]]
mesh_face_t1_area = get_triangle_area(P1, P4, P6)
mesh_face_t2_area = get_triangle_area(P2, P5, P4)
mesh_face_t3_area = get_triangle_area(P3, P6, P5)
mesh_face_t4_area = get_triangle_area(P4, P5, P6)
mesh_face_area = mesh_face_t1_area + mesh_face_t2_area + mesh_face_t3_area + mesh_face_t4_area
middle_node_area = mesh_face_area / 3.0
node_area_table.append((face_table[mf][0], 0))
node_area_table.append((face_table[mf][1], 0))
node_area_table.append((face_table[mf][2], 0))
node_area_table.append((face_table[mf][3], middle_node_area))
node_area_table.append((face_table[mf][4], middle_node_area))
node_area_table.append((face_table[mf][5], middle_node_area))
elif femmesh_facetype == 8: # 8 node femmesh face quad
# corner_node_area = -mesh_face_area / 12.0 (negativ!)
# mid-side nodes = mesh_face_area / 3.0
# P4_________P7________P3
# | / | \ |
# | t4 / | \ t3 |
# | / | \ |
# |/ | \|
# P8| t5 | t6 |P6
# |\ | / |
# | \ | / |
# | t1 \ | / t2 |
# |______\_|_/_______|
# P1 P5 P2
P1 = femnodes_mesh[face_table[mf][0]]
P2 = femnodes_mesh[face_table[mf][1]]
P3 = femnodes_mesh[face_table[mf][2]]
P4 = femnodes_mesh[face_table[mf][3]]
P5 = femnodes_mesh[face_table[mf][4]]
P6 = femnodes_mesh[face_table[mf][5]]
P7 = femnodes_mesh[face_table[mf][6]]
P8 = femnodes_mesh[face_table[mf][7]]
mesh_face_t1_area = get_triangle_area(P1, P5, P8)
mesh_face_t2_area = get_triangle_area(P5, P2, P6)
mesh_face_t3_area = get_triangle_area(P6, P3, P7)
mesh_face_t4_area = get_triangle_area(P7, P4, P8)
mesh_face_t5_area = get_triangle_area(P5, P7, P8)
mesh_face_t6_area = get_triangle_area(P5, P6, P7)
mesh_face_area = mesh_face_t1_area + mesh_face_t2_area + mesh_face_t3_area + mesh_face_t4_area + mesh_face_t5_area + mesh_face_t6_area
corner_node_area = -mesh_face_area / 12.0
middle_node_area = mesh_face_area / 3.0
node_area_table.append((face_table[mf][0], corner_node_area))
node_area_table.append((face_table[mf][1], corner_node_area))
node_area_table.append((face_table[mf][2], corner_node_area))
node_area_table.append((face_table[mf][3], corner_node_area))
node_area_table.append((face_table[mf][4], middle_node_area))
node_area_table.append((face_table[mf][5], middle_node_area))
node_area_table.append((face_table[mf][6], middle_node_area))
node_area_table.append((face_table[mf][7], middle_node_area))
return node_area_table
def get_ref_shape_node_sum_geom_table(node_geom_table):
# shape could be Edge or Face, geom could be lenght or area
# summ of legth or area for each node of the ref_shape
node_sum_geom_table = {}
for n, A in node_geom_table:
# print(n, ' --> ', A)
if n in node_sum_geom_table:
node_sum_geom_table[n] = node_sum_geom_table[n] + A
else:
node_sum_geom_table[n] = A
return node_sum_geom_table
def femelements_count_ok(femelement_table, count_femelements):
if count_femelements == len(femelement_table):
# print('Count FEM elements for the calculated node load distribution: ', count_femelements)
# print('Count FEM elements of the FreeCAD FEM mesh: ', len(femelement_table))
return True
else:
print('ERROR: femelement_table != count_femelements')
print('Count FEM elements for the calculated node load distribution: ', count_femelements)
print('Count FEM Elements of the FreeCAD FEM Mesh: ', len(femelement_table))
return False
def delete_duplicate_mesh_elements(refelement_table):
new_refelement_table = {} # duplicates deleted
for elem, nodes in refelement_table.items():
if sorted(nodes) not in sortlistoflistvalues(new_refelement_table.values()):
new_refelement_table[elem] = nodes
return new_refelement_table
def get_triangle_area(P1, P2, P3):
# import Part
# W = Part.Wire([Part.makeLine(P1,P2), Part.makeLine(P2,P3), Part.makeLine(P3,P1)])
# Part.show(Part.Face(W))
vec1 = P2 - P1
vec2 = P3 - P1
vec3 = vec1.cross(vec2)
return 0.5 * vec3.Length
def sortlistoflistvalues(listoflists):
new_list = []
for l in listoflists:
new_list.append(sorted(l))
return new_list
def is_solid_femmesh(femmesh):
if femmesh.VolumeCount > 0: # solid femmesh
return True
def has_no_face_data(femmesh):
if femmesh.FaceCount == 0: # femmesh has no face data, could be a edge femmesh or a solid femmesh without face data
return True
def is_face_femmesh(femmesh):
if femmesh.VolumeCount == 0 and femmesh.FaceCount > 0: # face femmesh
return True
def is_edge_femmesh(femmesh):
if femmesh.VolumeCount == 0 and femmesh.FaceCount == 0 and femmesh.EdgeCount > 0: # edge femmesh
return True
def get_three_non_colinear_nodes(nodes_coords):
# Code to obtain three non-colinear nodes on the PlaneRotation support face
# nodes_coords --> [(nodenumber, x, y, z), (nodenumber, x, y, z), ...]
if not nodes_coords:
print(len(nodes_coords))
print('Error: No nodes in nodes_coords')
return []
dum_max = [1, 2, 3, 4, 5, 6, 7, 8, 0]
for i in range(len(nodes_coords)):
for j in range(len(nodes_coords) - 1 - i):
x_1 = nodes_coords[j][1]
x_2 = nodes_coords[j + 1][1]
y_1 = nodes_coords[j][2]
y_2 = nodes_coords[j + 1][2]
z_1 = nodes_coords[j][3]
z_2 = nodes_coords[j + 1][3]
node_1 = nodes_coords[j][0]
node_2 = nodes_coords[j + 1][0]
distance = ((x_1 - x_2) ** 2 + (y_1 - y_2) ** 2 + (z_1 - z_2) ** 2) ** 0.5
if distance > dum_max[8]:
dum_max = [node_1, x_1, y_1, z_1, node_2, x_2, y_2, z_2, distance]
node_dis = [1, 0]
for i in range(len(nodes_coords)):
x_1 = dum_max[1]
x_2 = dum_max[5]
x_3 = nodes_coords[i][1]
y_1 = dum_max[2]
y_2 = dum_max[6]
y_3 = nodes_coords[i][2]
z_1 = dum_max[3]
z_2 = dum_max[7]
z_3 = nodes_coords[i][3]
node_3 = int(nodes_coords[j][0])
distance_1 = ((x_1 - x_3) ** 2 + (y_1 - y_3) ** 2 + (z_1 - z_3) ** 2) ** 0.5
distance_2 = ((x_3 - x_2) ** 2 + (y_3 - y_2) ** 2 + (z_3 - z_2) ** 2) ** 0.5
tot = distance_1 + distance_2
if tot > node_dis[1]:
node_dis = [node_3, tot]
node_1 = int(dum_max[0])
node_2 = int(dum_max[4])
print([node_1, node_2, node_3])
return [node_1, node_2, node_3]
def make_femmesh(mesh_data):
''' makes an FreeCAD FEM Mesh object from FEM Mesh data
'''
import Fem
mesh = Fem.FemMesh()
m = mesh_data
if ('Nodes' in m) and (len(m['Nodes']) > 0):
print("Found: nodes")
if (('Seg2Elem' in m) or
('Tria3Elem' in m) or
('Tria6Elem' in m) or
('Quad4Elem' in m) or
('Quad8Elem' in m) or
('Tetra4Elem' in m) or
('Tetra10Elem' in m) or
('Penta6Elem' in m) or
('Penta15Elem' in m) or
('Hexa8Elem' in m) or
('Hexa20Elem' in m)):
nds = m['Nodes']
print("Found: elements")
for i in nds:
n = nds[i]
mesh.addNode(n[0], n[1], n[2], i)
elms_hexa8 = m['Hexa8Elem']
for i in elms_hexa8:
e = elms_hexa8[i]
mesh.addVolume([e[0], e[1], e[2], e[3], e[4], e[5], e[6], e[7]], i)
elms_penta6 = m['Penta6Elem']
for i in elms_penta6:
e = elms_penta6[i]
mesh.addVolume([e[0], e[1], e[2], e[3], e[4], e[5]], i)
elms_tetra4 = m['Tetra4Elem']
for i in elms_tetra4:
e = elms_tetra4[i]
mesh.addVolume([e[0], e[1], e[2], e[3]], i)
elms_tetra10 = m['Tetra10Elem']
for i in elms_tetra10:
e = elms_tetra10[i]
mesh.addVolume([e[0], e[1], e[2], e[3], e[4], e[5], e[6], e[7], e[8], e[9]], i)
elms_penta15 = m['Penta15Elem']
for i in elms_penta15:
e = elms_penta15[i]
mesh.addVolume([e[0], e[1], e[2], e[3], e[4], e[5], e[6], e[7], e[8], e[9],
e[10], e[11], e[12], e[13], e[14]], i)
elms_hexa20 = m['Hexa20Elem']
for i in elms_hexa20:
e = elms_hexa20[i]
mesh.addVolume([e[0], e[1], e[2], e[3], e[4], e[5], e[6], e[7], e[8], e[9],
e[10], e[11], e[12], e[13], e[14], e[15], e[16], e[17], e[18], e[19]], i)
elms_tria3 = m['Tria3Elem']
for i in elms_tria3:
e = elms_tria3[i]
mesh.addFace([e[0], e[1], e[2]], i)
elms_tria6 = m['Tria6Elem']
for i in elms_tria6:
e = elms_tria6[i]
mesh.addFace([e[0], e[1], e[2], e[3], e[4], e[5]], i)
elms_quad4 = m['Quad4Elem']
for i in elms_quad4:
e = elms_quad4[i]
mesh.addFace([e[0], e[1], e[2], e[3]], i)
elms_quad8 = m['Quad8Elem']
for i in elms_quad8:
e = elms_quad8[i]
mesh.addFace([e[0], e[1], e[2], e[3], e[4], e[5], e[6], e[7]], i)
elms_seg2 = m['Seg2Elem']
for i in elms_seg2:
e = elms_seg2[i]
mesh.addEdge(e[0], e[1])
print("imported mesh: {} nodes, {} HEXA8, {} PENTA6, {} TETRA4, {} TETRA10, {} PENTA15".format(
len(nds), len(elms_hexa8), len(elms_penta6), len(elms_tetra4), len(elms_tetra10), len(elms_penta15)))
print("imported mesh: {} HEXA20, {} TRIA3, {} TRIA6, {} QUAD4, {} QUAD8, {} SEG2".format(
len(elms_hexa20), len(elms_tria3), len(elms_tria6), len(elms_quad4), len(elms_quad8), len(elms_seg2)))
else:
FreeCAD.Console.PrintError("No Elements found!\n")
else:
FreeCAD.Console.PrintError("No Nodes found!\n")
return mesh