FreeCAD/src/Mod/Fem/ccxFrdReader.py
Przemo Firszt 29044021cd FEM: Fix Von Mises equation
Reported-by: sgrogan and confirmed by drei

Signed-off-by: Przemo Firszt <przemo@firszt.eu>
2015-05-12 15:58:49 +01:00

203 lines
8.5 KiB
Python

#***************************************************************************
#* *
#* Copyright (c) 2013 - Joachim Zettler *
#* Copyright (c) 2013 - Juergen Riegel <FreeCAD@juergen-riegel.net> *
#* *
#* 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 *
#* *
#***************************************************************************
import FreeCAD,os
from math import pow,sqrt
__title__="FreeCAD Calculix library"
__author__ = "Juergen Riegel "
__url__ = "http://www.freecadweb.org"
if open.__module__ == '__builtin__':
pyopen = open # because we'll redefine open below
# read a calculix result file and extract the nodes, displacement vectores and stress values.
def readResult(frd_input) :
input = pyopen(frd_input,"r")
nodes = {}
disp = {}
stress = {}
elements = {}
disp_found = False
nodes_found = False
stress_found = False
elements_found = False
elem = -1
elemType = 0
while True:
line=input.readline()
if not line: break
#Check if we found nodes section
if line[4:6] == "2C":
nodes_found = True
#first lets extract the node and coordinate information from the results file
if nodes_found and (line[1:3] == "-1"):
elem = int(line[4:13])
nodes_x = float(line[13:25])
nodes_y = float(line[25:37])
nodes_z = float(line[37:49])
nodes[elem] = FreeCAD.Vector(nodes_x,nodes_y,nodes_z)
#Check if we found nodes section
if line[4:6] == "3C":
elements_found = True
#first lets extract element number
if elements_found and (line[1:3] == "-1"):
elem = int(line[4:13])
elemType = int(line[14:18])
#then the 10 id's for the Tet10 element
if elements_found and (line[1:3] == "-2") and elemType == 6 :
node_id_2 = int(line[3:13])
node_id_1 = int(line[13:23])
node_id_3 = int(line[23:33])
node_id_4 = int(line[33:43])
node_id_5 = int(line[43:53])
node_id_7 = int(line[53:63])
node_id_6 = int(line[63:73])
node_id_9 = int(line[73:83])
node_id_8 = int(line[83:93])
node_id_10 = int(line[93:103])
elements[elem] = (node_id_1,node_id_2,node_id_3,node_id_4,node_id_5,node_id_6,node_id_7,node_id_8,node_id_9,node_id_10)
#Check if we found displacement section
if line[5:9] == "DISP":
disp_found = True
#we found a displacement line in the frd file
if disp_found and (line[1:3] == "-1"):
elem = int(line[4:13])
disp_x = float(line[13:25])
disp_y = float(line[25:37])
disp_z = float(line[37:49])
disp[elem] = FreeCAD.Vector(disp_x,disp_y,disp_z)
if line[5:11] == "STRESS":
stress_found = True
#we found a displacement line in the frd file
if stress_found and (line[1:3] == "-1"):
elem = int(line[4:13])
stress_1 = float(line[13:25])
stress_2 = float(line[25:37])
stress_3 = float(line[37:49])
stress_4 = float(line[49:61])
stress_5 = float(line[61:73])
stress_6 = float(line[73:85])
stress[elem] = (stress_1,stress_2,stress_3,stress_4,stress_5,stress_6)
#Check for the end of a section
if line[1:3] == "-3":
#the section with the displacements and the nodes ended
disp_found = False
nodes_found = False
stress_found = False
elements_found = False
input.close()
FreeCAD.Console.PrintLog('Read Calculix result: ' + `len(nodes)` + ' Nodes, ' + `len(disp)` + ' Displacements and ' + `len(stress)` + ' Stress values\n')
return {'Nodes':nodes,'Tet10Elem':elements,'Displacement':disp,'Stress':stress}
def importFrd(filename,Analysis=None):
m = readResult(filename);
MeshObject = None
if(len(m) > 0):
import Fem
if Analysis == None:
AnalysisName = os.path.splitext(os.path.basename(filename))[0]
AnalysisObject = FreeCAD.ActiveDocument.addObject('Fem::FemAnalysis','Analysis')
AnalysisObject.Label = AnalysisName
else:
AnalysisObject = Analysis
if(m.has_key('Tet10Elem') and m.has_key('Nodes') and not Analysis ):
mesh = Fem.FemMesh()
nds = m['Nodes']
for i in nds:
n = nds[i]
mesh.addNode(n[0],n[1],n[2],i)
elms = m['Tet10Elem']
for i in elms:
e = elms[i]
mesh.addVolume([e[0],e[1],e[2],e[3],e[4],e[5],e[6],e[7],e[8],e[9]],i)
if len(nds) > 0:
MeshObject = FreeCAD.ActiveDocument.addObject('Fem::FemMeshObject','ResultMesh')
MeshObject.FemMesh = mesh
AnalysisObject.Member = AnalysisObject.Member + [MeshObject]
if(m.has_key('Displacement')):
disp = m['Displacement']
if len(disp)>0:
o = FreeCAD.ActiveDocument.addObject('Fem::FemResultVector','Displacement')
o.Values = disp.values()
o.DataType = 'Displacement'
o.ElementNumbers = disp.keys()
if(MeshObject):
o.Mesh = MeshObject
AnalysisObject.Member = AnalysisObject.Member + [o]
if(m.has_key('Stress')):
stress = m['Stress']
if len(stress)>0:
o = FreeCAD.ActiveDocument.addObject('Fem::FemResultValue','MisesStress')
mstress = []
for i in stress.values():
# van mises stress (http://en.wikipedia.org/wiki/Von_Mises_yield_criterion)
s11 = i[0]
s22 = i[1]
s33 = i[2]
s12 = i[3]
s23 = i[4]
s31 = i[5]
s11s22 = pow(s11 - s22, 2)
s22s33 = pow(s22 - s33, 2)
s33s11 = pow(s33 - s11, 2)
s12s23s31 = 6 * (pow(s12, 2) + pow(s23, 2) * pow(s31, 2))
mstress.append(sqrt(0.5 * (s11s22 + s22s33 + s33s11 + s12s23s31)))
o.Values = mstress
o.DataType = 'VonMisesStress'
o.ElementNumbers = stress.keys()
if(MeshObject):
o.Mesh = MeshObject
AnalysisObject.Member = AnalysisObject.Member + [o]
if(FreeCAD.GuiUp):
import FemGui, FreeCADGui
if FreeCADGui.activeWorkbench().name() != 'FemWorkbench':
FreeCADGui.activateWorkbench("FemWorkbench")
FemGui.setActiveAnalysis(AnalysisObject)
def insert(filename,docname):
"called when freecad wants to import a file"
try:
doc = FreeCAD.getDocument(docname)
except NameError:
doc = FreeCAD.newDocument(docname)
FreeCAD.ActiveDocument = doc
importFrd(filename)
def open(filename):
"called when freecad opens a file"
docname = os.path.splitext(os.path.basename(filename))[0]
insert(filename,docname)