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FEM: ccx frd reader: add reading and calculating principal stresses

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vdwalts 2016-08-01 21:58:00 +01:00 committed by wmayer
parent d4e3ea7cb6
commit 1d61226313
2 changed files with 59 additions and 5 deletions
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8
src/Mod/Fem/FemTools.py
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@ -495,6 +495,10 @@ class FemTools(QtCore.QRunnable, QtCore.QObject):
# - U1, U2, U3 - deformation # - U1, U2, U3 - deformation
# - Uabs - absolute deformation # - Uabs - absolute deformation
# - Sabs - Von Mises stress # - Sabs - Von Mises stress
# Prin1 Principal stress 1
# Prin2 Principal stress 2
# Prin3 Principal stress 3
# MaxSear maximum shear stress
# - None - always return (0.0, 0.0, 0.0) # - None - always return (0.0, 0.0, 0.0)
def get_stats(self, result_type): def get_stats(self, result_type):
stats = (0.0, 0.0, 0.0) stats = (0.0, 0.0, 0.0)
@ -505,6 +509,10 @@ class FemTools(QtCore.QRunnable, QtCore.QObject):
"U3": (m.Stats[6], m.Stats[7], m.Stats[8]), "U3": (m.Stats[6], m.Stats[7], m.Stats[8]),
"Uabs": (m.Stats[9], m.Stats[10], m.Stats[11]), "Uabs": (m.Stats[9], m.Stats[10], m.Stats[11]),
"Sabs": (m.Stats[12], m.Stats[13], m.Stats[14]), "Sabs": (m.Stats[12], m.Stats[13], m.Stats[14]),
"MaxPrin": (m.Stats[15], m.Stats[16], m.Stats[17]),
"MidPrin": (m.Stats[18], m.Stats[19], m.Stats[20]),
"MinPrin": (m.Stats[21], m.Stats[22], m.Stats[23]),
"MaxShear": (m.Stats[24], m.Stats[25], m.Stats[26]),
"None": (0.0, 0.0, 0.0)} "None": (0.0, 0.0, 0.0)}
stats = match[result_type] stats = match[result_type]
return stats return stats

56
src/Mod/Fem/ccxFrdReader.py
View File

@ -26,6 +26,7 @@
import FreeCAD import FreeCAD
import os import os
from math import pow, sqrt from math import pow, sqrt
import numpy as np
__title__ = "FreeCAD Calculix library" __title__ = "FreeCAD Calculix library"
__author__ = "Juergen Riegel , Michael Hindley, Bernd Hahnebach" __author__ = "Juergen Riegel , Michael Hindley, Bernd Hahnebach"
@ -351,6 +352,18 @@ def calculate_von_mises(i):
return vm_stress return vm_stress
def calculate_principal_stress(i):
sigma = np.array([[i[0], i[3], i[4]],
[i[3], i[1], i[5]],
[i[4], i[5], i[2]]])
# compute principal stresses
eigvals = list(np.linalg.eigvalsh(sigma))
eigvals.sort()
eigvals.reverse()
maxshear = (eigvals[0] - eigvals[2]) / 2.0
return (eigvals[0], eigvals[1], eigvals[2], maxshear)
def importFrd(filename, analysis=None, result_name_prefix=None): def importFrd(filename, analysis=None, result_name_prefix=None):
if result_name_prefix is None: if result_name_prefix is None:
result_name_prefix = '' result_name_prefix = ''
@ -404,7 +417,7 @@ def importFrd(filename, analysis=None, result_name_prefix=None):
break break
disp = result_set['disp'] disp = result_set['disp']
l = len(disp) no_of_values = len(disp)
displacement = [] displacement = []
for k, v in disp.iteritems(): for k, v in disp.iteritems():
displacement.append(v) displacement.append(v)
@ -446,13 +459,30 @@ def importFrd(filename, analysis=None, result_name_prefix=None):
stress = result_set['stress'] stress = result_set['stress']
if len(stress) > 0: if len(stress) > 0:
mstress = [] mstress = []
prinstress1 = []
prinstress2 = []
prinstress3 = []
shearstress = []
for i in stress.values(): for i in stress.values():
mstress.append(calculate_von_mises(i)) mstress.append(calculate_von_mises(i))
prin1, prin2, prin3, shear = calculate_principal_stress(i)
prinstress1.append(prin1)
prinstress2.append(prin2)
prinstress3.append(prin3)
shearstress.append(shear)
if eigenmode_number > 0: if eigenmode_number > 0:
results.StressValues = map((lambda x: x * scale), mstress) results.StressValues = map((lambda x: x * scale), mstress)
results.PrincipalMax = map((lambda x: x * scale), prinstress1)
results.PrincipalMed = map((lambda x: x * scale), prinstress2)
results.PrincipalMin = map((lambda x: x * scale), prinstress3)
results.MaxShear = map((lambda x: x * scale), shearstress)
results.Eigenmode = eigenmode_number results.Eigenmode = eigenmode_number
else: else:
results.StressValues = mstress results.StressValues = mstress
results.PrincipalMax = prinstress1
results.PrincipalMed = prinstress2
results.PrincipalMin = prinstress3
results.MaxShear = shearstress
if (results.NodeNumbers != 0 and results.NodeNumbers != stress.keys()): if (results.NodeNumbers != 0 and results.NodeNumbers != stress.keys()):
print("Inconsistent FEM results: element number for Stress doesn't equal element number for Displacement {} != {}" print("Inconsistent FEM results: element number for Stress doesn't equal element number for Displacement {} != {}"
@ -461,11 +491,23 @@ def importFrd(filename, analysis=None, result_name_prefix=None):
x_min, y_min, z_min = map(min, zip(*displacement)) x_min, y_min, z_min = map(min, zip(*displacement))
sum_list = map(sum, zip(*displacement)) sum_list = map(sum, zip(*displacement))
x_avg, y_avg, z_avg = [i / l for i in sum_list] x_avg, y_avg, z_avg = [i / no_of_values for i in sum_list]
s_max = max(results.StressValues) s_max = max(results.StressValues)
s_min = min(results.StressValues) s_min = min(results.StressValues)
s_avg = sum(results.StressValues) / l s_avg = sum(results.StressValues) / no_of_values
p1_min = min(results.PrincipalMax)
p1_avg = sum(results.PrincipalMax) / no_of_values
p1_max = max(results.PrincipalMax)
p2_min = min(results.PrincipalMed)
p2_avg = sum(results.PrincipalMed) / no_of_values
p2_max = max(results.PrincipalMed)
p3_min = min(results.PrincipalMin)
p3_avg = sum(results.PrincipalMin) / no_of_values
p3_max = max(results.PrincipalMin)
ms_min = min(results.MaxShear)
ms_avg = sum(results.MaxShear) / no_of_values
ms_max = max(results.MaxShear)
disp_abs = [] disp_abs = []
for d in displacement: for d in displacement:
@ -474,13 +516,17 @@ def importFrd(filename, analysis=None, result_name_prefix=None):
a_max = max(disp_abs) a_max = max(disp_abs)
a_min = min(disp_abs) a_min = min(disp_abs)
a_avg = sum(disp_abs) / l a_avg = sum(disp_abs) / no_of_values
results.Stats = [x_min, x_avg, x_max, results.Stats = [x_min, x_avg, x_max,
y_min, y_avg, y_max, y_min, y_avg, y_max,
z_min, z_avg, z_max, z_min, z_avg, z_max,
a_min, a_avg, a_max, a_min, a_avg, a_max,
s_min, s_avg, s_max] s_min, s_avg, s_max,
p1_min, p1_avg, p1_max,
p2_min, p2_avg, p2_max,
p3_min, p3_avg, p3_max,
ms_min, ms_avg, ms_max]
analysis_object.Member = analysis_object.Member + [results] analysis_object.Member = analysis_object.Member + [results]
if(FreeCAD.GuiUp): if(FreeCAD.GuiUp):