# Set constitutive properties
rho = 2500.0 # density, kg/m^3
E = 70e9 # elastic modulus, Pa
nu = 0.3 # poisson's ratio
kcorr = 5.0 / 6.0 # shear correction factor
ys = 350e6 # yield stress, Pa
min_thickness = 0.001
max_thickness = 0.020
thickness = 0.005
# Loop over components, creating stiffness and element object for each
num_components = struct_mesh.getNumComponents()
for i in range(num_components):
descriptor = struct_mesh.getElementDescript(i)
stiff = constitutive.isoFSDT(rho, E, nu, kcorr, ys, thickness, i,
min_thickness, max_thickness)
element = None
if descriptor in ["CQUAD", "CQUADR", "CQUAD4"]:
element = elements.MITCShell(2, stiff, component_num=i)
struct_mesh.setElement(i, element)
# Create tacs assembler object
tacs = struct_mesh.createTACS(6)
res = tacs.createVec()
ans = tacs.createVec()
mat = tacs.createFEMat()
# Create distributed node vector from TACS Assembler object and extract the
# nodes
struct_X_vec = tacs.createNodeVec()
tacs.getNodes(struct_X_vec)
# There are 6 degrees of freedom per node
vars_per_node = 6
# Create the TACS assembler object
tacs = TACS.Assembler.create(comm, vars_per_node,
num_nodes, num_elements)
elems = []
elem_conn = []
# Add all the elements
for j in range(ny):
for i in range(nx):
# Create the shell element class
dv_num = i + nx*j
stiff = constitutive.isoFSDT(rho, E, nu, kcorr, ys, t,
dv_num, min_t, max_t)
# stiff.setRefAxis([0.0, 1.0, 0.0])
shell_element = elements.MITCShell(2, stiff)
elems.append(shell_element)
# Set the element connectivity
elem_conn.append([i + (nx+1)*j,
i+1 + (nx+1)*j,
i + (nx+1)*(j+1),
i+1 + (nx+1)*(j+1)])
# Create the connectivity array
conn = np.array(elem_conn, dtype=np.intc).flatten()
ptr = np.arange(0, len(conn)+1, 4, dtype=np.intc)
def __init__(self, comm, bdf_name):
self.comm = comm
struct_mesh = TACS.MeshLoader(self.comm)
struct_mesh.scanBDFFile(bdf_name)
# Set constitutive properties
rho = 2500.0 # density, kg/m^3
E = 70e9 # elastic modulus, Pa
nu = 0.3 # poisson's ratio
kcorr = 5.0 / 6.0 # shear correction factor
ys = 350e6 # yield stress, Pa
min_thickness = 0.002
max_thickness = 0.20
thickness = 0.02
# Loop over components, creating stiffness and element object for each
num_components = struct_mesh.getNumComponents()
for i in range(num_components):
descriptor = struct_mesh.getElementDescript(i)
# Set the design variable index
design_variable_index = i
stiff = constitutive.isoFSDT(rho, E, nu, kcorr, ys, thickness,
design_variable_index, min_thickness,
max_thickness)
element = None
# Create the element object
if descriptor in ["CQUAD", "CQUADR", "CQUAD4"]:
element = elements.MITCShell(2, stiff, component_num=i)
struct_mesh.setElement(i, element)
# Create tacs assembler object from mesh loader
self.assembler = struct_mesh.createTACS(6)
# Create the KS Function
ksWeight = 50.0
self.funcs = [
functions.StructuralMass(self.assembler),
functions.KSFailure(self.assembler, ksWeight)
]
# Create the forces
self.forces = self.assembler.createVec()
force_array = self.forces.getArray()
force_array[2::6] += 100.0 # uniform load in z direction
self.assembler.applyBCs(self.forces)
# Set up the solver
self.ans = self.assembler.createVec()
self.res = self.assembler.createVec()
self.adjoint = self.assembler.createVec()
self.dfdu = self.assembler.createVec()
self.mat = self.assembler.createFEMat()
self.pc = TACS.Pc(self.mat)
subspace = 100
restarts = 2
self.gmres = TACS.KSM(self.mat, self.pc, subspace, restarts)
# Scale the mass objective so that it is O(10)
self.mass_scale = 1e-3
# Scale the thickness variables so that they are measured in
# mm rather than meters
self.thickness_scale = 1000.0
# The number of thickness variables in the problem
self.nvars = num_components
# The number of constraints (1 global stress constraint that
# will use the KS function)
self.ncon = 1
# Initialize the base class - this will run the same problem
# on all processors
super(uCRM_VonMisesMassMin, self).__init__(MPI.COMM_SELF, self.nvars,
self.ncon)
# Set the inequality options for this problem in ParOpt:
# The dense constraints are inequalities c(x) >= 0 and
# use both the upper/lower bounds
self.setInequalityOptions(dense_ineq=True,
use_lower=True,
use_upper=True)
# For visualization
flag = (TACS.ToFH5.NODES | TACS.ToFH5.DISPLACEMENTS
| TACS.ToFH5.STRAINS | TACS.ToFH5.EXTRAS)
self.f5 = TACS.ToFH5(self.assembler, TACS.PY_SHELL, flag)
self.iter_count = 0
return
def __init__(self,comm,tacs_comm,model,n_tacs_procs):
super(CRMtacs,self).__init__(comm,tacs_comm,model)
self.tacs_proc = False
if comm.Get_rank() < n_tacs_procs:
self.tacs_proc = True
struct_mesh = TACS.MeshLoader(tacs_comm)
struct_mesh.scanBDFFile("CRM_box_2nd.bdf")
# Set constitutive properties
rho = 2500.0 # density, kg/m^3
E = 70.0e9 # elastic modulus, Pa
nu = 0.3 # poisson's ratio
kcorr = 5.0 / 6.0 # shear correction factor
ys = 350e6 # yield stress, Pa
min_thickness = 0.001
max_thickness = 0.100
thickness = 0.015
spar_thick = 0.015
# Loop over components in mesh, creating stiffness and element
# object for each
map = np.zeros(240,dtype=int)
num_components = struct_mesh.getNumComponents()
for i in range(num_components):
descript = struct_mesh.getElementDescript(i)
comp = struct_mesh.getComponentDescript(i)
if 'SPAR' in comp:
t = spar_thick
else:
t = thickness
stiff = constitutive.isoFSDT(rho, E, nu, kcorr, ys, t, i,
min_thickness, max_thickness)
element = None
if descript in ["CQUAD", "CQUADR", "CQUAD4"]:
element = elements.MITCShell(2,stiff,component_num=i)
struct_mesh.setElement(i, element)
# Create map
if 'LE_SPAR' in comp:
segnum = int(comp[-2:])
map[i] = segnum
if 'TE_SPAR' in comp:
segnum = int(comp[-2:])
map[i] = segnum + 48
if 'IMPDISP' in comp:
map[i] = i
elif 'RIB' in comp:
segnum = int(comp[-9:-7]) - 1
if segnum > 3:
segnum -= 1
map[i] = segnum + 188
if 'U_SKIN' in comp:
segnum = int(comp[-9:-7]) - 1
map[i] = segnum + 92
if 'L_SKIN' in comp:
segnum = int(comp[-9:-7]) - 1
map[i] = segnum + 140
self.dof = 6
# Create tacs assembler object
tacs = struct_mesh.createTACS(self.dof)
res = tacs.createVec()
ans = tacs.createVec()
mat = tacs.createFEMat()
# Create distributed node vector from TACS Assembler object and
# extract the node locations
nbodies = 1
struct_X = []
struct_nnodes = []
for body in range(nbodies):
self.struct_X_vec = tacs.createNodeVec()
tacs.getNodes(self.struct_X_vec)
struct_X.append(self.struct_X_vec.getArray())
struct_nnodes.append(len(struct_X) / 3)
tacs.setNodes(self.struct_X_vec)
# Create the preconditioner for the corresponding matrix
pc = TACS.Pc(mat)
alpha = 1.0
beta = 0.0
gamma = 0.0
tacs.assembleJacobian(alpha,beta,gamma,res,mat)
pc.factor()
# Create GMRES object for structural adjoint solves
nrestart = 0 # number of restarts before giving up
m = 30 # size of Krylov subspace (max # of iterations)
gmres = TACS.KSM(mat, pc, m, nrestart)
# Initialize member variables pertaining to TACS
self.tacs = tacs
self.res = res
self.ans = ans
self.mat = mat
self.pc = pc
self.struct_X = struct_X
self.struct_nnodes = struct_nnodes
self.gmres = gmres
self.svsens = tacs.createVec()
self.struct_rhs_vec = tacs.createVec()
self.psi_S_vec = tacs.createVec()
psi_S = self.psi_S_vec.getArray()
self.psi_S = np.zeros((psi_S.size,self.nfunc),dtype=TACS.dtype)
self.ans_array = []
for scenario in range(len(model.scenarios)):
self.ans_array.append(self.ans.getArray().copy())
self.initialize(model.scenarios[0],model.bodies)