def flux_offset(self, mesh, element, flux, masterpos, time, smallsystem):
# Retrieve the plastic strain field and evaluate it at this
# masterposition.
ep_val = symmmatrix.SymmMatrix3()
ep = field.getField('Plastic')
efi = element.funcnode_iterator()
while not efi.end():
coef = efi.shapefunction(masterpos)
ep_output = ep.output(mesh, efi.funcnode())
ep_val += ep_output.valuePtr() * coef
efi += 1
# Now ep_val contains the plastic strain at this gausspoint.
# We can do the arithmetic. Note that this assumes the same
# gausspoint set from one iteration to the next, which will in
# general be a bad assumption.
modulus = self.elasticity.cijkl(mesh, element, masterpos)
ij = fieldindex.SymTensorIterator()
while (not ij.end()):
offset = 0.0
kl = ep_val.getIterator()
while (not kl.end()):
idx = kl.integer()
cijkl = modulus[ij.integer(), kl.integer()]
if idx < 3:
offset += cijkl * ep_val[kl]
else:
offset += 2.0 * cijkl * ep_val[kl]
kl.next()
smallsystem.add_offset_element(ij, offset)
ij.next()
def evaluate_constraint(self, mesh, element, eqn, masterpos, smallsystem):
# TODO: Test for the right equation.
# Compute the stress -- start with the strain.
strain = symmmatrix.SymmMatrix3
ep = field.getField('Plastic')
efi = element.funcnode_iterator()
while not efi.end():
coef = efi.shapefunction(masterpos)
ep_output = ep.output(mesh, efi.funcnode())
strain -= ep_output.valuePtr() * coef
efi += 1
disp = field.getField('Displacement')
efi = element.funcnode_iterator()
while not efi.end():
ddx = efi.dshapefunction(0, masterpos)
ddy = efi.dshapefunction(1, masterpos)
uxx = disp(efi, 0).value() * ddx
uxy = disp(efi, 0).value() * ddy
uyx = disp(efi, 1).value() * ddx
uyy = disp(efi, 1).value() * ddy
strain.set(0, 0, strain.get(0, 0) + uxx)
strain.set(0, 1, strain.get(0, 1) + (0.5 * uxy + uyx))
strain.set(1, 1, strain.get(1, 1) + uyy)
try:
ops = field.getField('Displacement_z')
except:
pass
else:
efi = element.funcnode_iterator()
while not efi.end():
uxz = ops(efi, 0).value()
uyz = ops(efi, 1).value()
uyz = ops(efi, 2).value()
strain.set(0, 2, strain.get(0, 2) + uxz)
strain.set(1, 2, strain.get(1, 2) + uyz)
strain.set(2, 2, strain.get(2, 2) + uzz)
# At this point, "strain" contains the elastic strain,
# geometric minus plastic.
modulus = self.elasticity.cijkl(mesh, element, masterpos)
ij = fieldindex.SymTensorIterator()
while (not ij.end()):
stressij = 0.0
kl = ep_val.getIterator()
while (not kl.end()):
idx = kl.integer
cijkl = modulus[ij.integer(), kl.integer()]
if idx < 3:
stressij += cijkl * strain[kl]
else:
stressij += 2.0 * cijkl * strain[kl]
kl.next()
# Accumulate the stress somewhere.
ij.next()
def flux_offset(self, mesh, element, flux, point, time, fluxdata):
cijkl = self.elasticity.cijkl(mesh, element, point)
strain0 = symmmatrix.SymmMatrix3(0.1, 0.1, 0.1, 0, 0, 0)
ij = problem.Stress.iterator(planarity.ALL_INDICES)
while not ij.end():
kl = fieldindex.SymTensorIterator()
while not kl.end():
strain_kl = strain0.get(kl.row(), kl.col()) # TODO: too ugly
if kl.diagonal():
fluxdata.add_offset_vector_element(
ij, cijkl[ij.integer(), kl.integer()] * strain_kl)
else:
fluxdata.add_offset_vector_element(
ij,
2.0 * cijkl[ij.integer(), kl.integer()] * strain_kl)
kl.next()
ij.next()