def test_aerostruct_optimization(self):
OAS_prob = OASProblem({
'type': 'aerostruct',
'optimize': True,
'with_viscous': True,
'record_db': False
})
surf_dict = {
'num_y': 7,
'num_x': 2,
'wing_type': 'CRM',
'CD0': 0.015,
'symmetry': False,
'num_twist_cp': 2,
'num_thickness_cp': 2
}
OAS_prob.add_surface(surf_dict)
OAS_prob.add_desvar('wing.twist_cp', lower=-15., upper=15.)
OAS_prob.add_desvar('wing.thickness_cp',
lower=0.01,
upper=0.5,
scaler=1e2)
OAS_prob.add_constraint('wing_perf.failure', upper=0.)
OAS_prob.add_constraint('wing_perf.thickness_intersects', upper=0.)
OAS_prob.add_desvar('alpha', lower=-10., upper=10.)
OAS_prob.add_constraint('L_equals_W', equals=0.)
OAS_prob.add_objective('fuelburn', scaler=1e-5)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['fuelburn'],
96889.255792361335,
places=0)
self.assertAlmostEqual(prob['wing_perf.failure'], 0., places=4)
self.assertAlmostEqual(prob['CM'][1],
-0.14194155955058388,
places=2)
def test_aero_optimization_fd(self):
# Need to use SLSQP here because SNOPT finds a different optimum
OAS_prob = OASProblem({'type' : 'aero',
'optimize' : True,
'record_db' : False,
'optimizer' : 'SLSQP',
'force_fd' : True})
OAS_prob.add_surface()
OAS_prob.add_desvar('wing.twist_cp', lower=-10., upper=15.)
OAS_prob.add_desvar('wing.sweep', lower=10., upper=30.)
OAS_prob.add_desvar('wing.dihedral', lower=-10., upper=20.)
OAS_prob.add_desvar('wing.taper', lower=.5, upper=2.)
OAS_prob.add_constraint('wing_perf.CL', equals=0.5)
OAS_prob.add_objective('wing_perf.CD', scaler=1e4)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['wing_perf.CD'], 0.0038513637269919619, places=5)
def test_aero_multiple_opt(self):
OAS_prob = OASProblem({
'type': 'aero',
'optimize': True,
'record_db': False
})
surf_dict = {
'name': 'wing',
'span': 5.,
'num_y': 3,
'span_cos_spacing': 0.
}
OAS_prob.add_surface(surf_dict)
surf_dict.update({
'name': 'tail',
'offset': np.array([0., 0., 10.])
})
OAS_prob.add_surface(surf_dict)
OAS_prob.add_desvar('tail.twist_cp', lower=-10., upper=15.)
OAS_prob.add_desvar('tail.sweep', lower=10., upper=30.)
OAS_prob.add_desvar('tail.dihedral', lower=-10., upper=20.)
OAS_prob.add_desvar('tail.taper', lower=.5, upper=2.)
OAS_prob.add_constraint('tail_perf.CL', equals=0.5)
OAS_prob.add_objective('tail_perf.CD', scaler=1e4)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['wing_perf.CL'],
0.41532382375677429,
places=4)
self.assertAlmostEqual(prob['tail_perf.CL'], .5, places=5)
self.assertAlmostEqual(prob['wing_perf.CD'],
.0075400306289957033,
places=5)
self.assertAlmostEqual(prob['tail_perf.CD'],
0.008087914662238814,
places=5)
def test_aerostruct_analysis_symmetry_deriv(self):
OAS_prob = OASProblem({'type' : 'aerostruct',
'optimize' : False,
'record_db' : True})
surf_dict = {'symmetry' : True,
'num_y' : 7,
'num_x' : 2,
'wing_type' : 'CRM',
'CD0' : 0.015}
OAS_prob.add_surface(surf_dict)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
data = prob.check_partial_derivatives(out_stream=None)
new_dict = {}
for key1 in data.keys():
for key2 in data[key1].keys():
for key3 in data[key1][key2].keys():
if 'rel' in key3:
error = np.linalg.norm(data[key1][key2][key3])
new_key = key1+'_'+key2[0]+'_'+key2[1]+'_'+key3
new_dict.update({new_key : error})
for key in new_dict.keys():
error = new_dict[key]
if not np.isnan(error):
# The FD check is not valid for these cases
if 'assembly_forces_Iy' in key or 'assembly_forces_J' in key or \
'assembly_forces_A' in key or 'assembly_K_loads' in key or \
'assembly_forces_loads' in key or 'assembly_forces_Iz' in key or \
'assembly_forces_nodes' in key or 'CM_wing_S_ref' in key or \
'CM_rho' in key:
pass
elif 'K' in key or 'vonmises' in key:
self.assertAlmostEqual(0., error, places=0)
else:
self.assertAlmostEqual(0., error, places=2)
def test_aero_viscous_optimization(self):
OAS_prob = OASProblem({
'type': 'aero',
'optimize': True,
'record_db': False,
'with_viscous': True
})
OAS_prob.add_surface()
OAS_prob.add_desvar('wing.twist_cp', lower=-10., upper=15.)
OAS_prob.add_desvar('wing.sweep', lower=10., upper=30.)
OAS_prob.add_desvar('wing.dihedral', lower=-10., upper=20.)
OAS_prob.add_constraint('wing_perf.CL', equals=0.5)
OAS_prob.add_objective('wing_perf.CD', scaler=1e4)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['wing_perf.CD'],
0.019234984422361764,
places=5)
def test_aerostruct_analysis_symmetry(self):
OAS_prob = OASProblem({
'type': 'aerostruct',
'optimize': False,
'record_db': False
})
surf_dict = {
'symmetry': True,
'num_y': 13,
'num_x': 2,
'wing_type': 'CRM',
'CD0': 0.015
}
OAS_prob.add_surface(surf_dict)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['wing_perf.CL'], 0.57096081806728627)
self.assertAlmostEqual(prob['wing_perf.failure'],
-0.8969902215221538,
places=5)
self.assertAlmostEqual(prob['fuelburn'], 105120.8601409321, places=2)
def test_aerostruct_analysis(self):
OAS_prob = OASProblem({
'type': 'aerostruct',
'optimize': False,
'record_db': False
})
surf_dict = {
'num_y': 13,
'num_x': 2,
'wing_type': 'CRM',
'CD0': 0.015,
'symmetry': False
}
OAS_prob.add_surface(surf_dict)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['wing_perf.CL'], 0.53470610411546438)
self.assertAlmostEqual(prob['wing_perf.failure'],
-0.88555523062055341,
places=5)
self.assertAlmostEqual(prob['fuelburn'], 99367.43763782426, places=2)
def test_aerostruct_optimization_symmetry_multiple(self):
OAS_prob = OASProblem({'type' : 'aerostruct',
'optimize' : True,
'with_viscous' : True,
'record_db' : False})
surf_dict = {'name' : 'wing',
'symmetry' : True,
'num_y' : 5,
'num_x' : 2,
'wing_type' : 'CRM',
'CD0' : 0.015,
'num_twist_cp' : 2,
'num_thickness_cp' : 2}
OAS_prob.add_surface(surf_dict)
surf_dict.update({'name' : 'tail',
'offset':np.array([10., 0., 10.])})
OAS_prob.add_surface(surf_dict)
# Add design variables and constraints for both the wing and tail
OAS_prob.add_desvar('wing.twist_cp', lower=-15., upper=15.)
OAS_prob.add_desvar('wing.thickness_cp', lower=0.01, upper=0.5, scaler=1e2)
OAS_prob.add_constraint('wing_perf.failure', upper=0.)
OAS_prob.add_constraint('wing_perf.thickness_intersects', upper=0.)
OAS_prob.add_desvar('tail.twist_cp', lower=-15., upper=15.)
OAS_prob.add_desvar('tail.thickness_cp', lower=0.01, upper=0.5, scaler=1e2)
OAS_prob.add_constraint('tail_perf.failure', upper=0.)
OAS_prob.add_constraint('tail_perf.thickness_intersects', upper=0.)
OAS_prob.add_desvar('alpha', lower=-10., upper=10.)
OAS_prob.add_constraint('L_equals_W', equals=0.)
OAS_prob.add_objective('fuelburn', scaler=1e-5)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['fuelburn'], 171158.11644279823, places=1)
self.assertAlmostEqual(prob['wing_perf.failure'], 0, places=5)
def test_struct_optimization_symmetry(self):
OAS_prob = OASProblem({
'type': 'struct',
'optimize': True,
'record_db': False
})
OAS_prob.add_surface({'t_over_c': 0.15})
OAS_prob.add_desvar('wing.thickness_cp',
lower=0.001,
upper=0.25,
scaler=1e2)
OAS_prob.add_constraint('wing.failure', upper=0.)
OAS_prob.add_constraint('wing.thickness_intersects', upper=0.)
OAS_prob.add_objective('wing.structural_weight', scaler=1e-3)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['wing.structural_weight'],
1144.8503583047038,
places=2)
def test_aero_analysis_flat_side_by_side(self):
OAS_prob = OASProblem({'type' : 'aero',
'optimize' : False,
'record_db' : False})
OAS_prob.add_surface({'name' : 'wing',
'span' : 5.,
'num_y' : 3,
'span_cos_spacing' : 0.,
'symmetry' : False,
'offset' : np.array([0., -2.5, 0.])})
OAS_prob.add_surface({'name' : 'tail',
'span' : 5.,
'num_y' : 3,
'span_cos_spacing' : 0.,
'symmetry' : False,
'offset' : np.array([0., 2.5, 0.])})
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['wing_perf.CL'], 0.46173591841167183, places=5)
self.assertAlmostEqual(prob['tail_perf.CL'], 0.46173591841167183, places=5)
self.assertAlmostEqual(prob['wing_perf.CD'], .005524603647, places=5)
self.assertAlmostEqual(prob['tail_perf.CD'], .005524603647, places=5)
def test_aerostruct_optimization_symmetry(self):
OAS_prob = OASProblem({
'type': 'aerostruct',
'optimize': True,
'with_viscous': True,
'record_db': False
})
surf_dict = {
'symmetry': True,
'num_y': 7,
'num_x': 3,
'wing_type': 'CRM',
'CD0': 0.015,
'num_twist_cp': 2,
'num_thickness_cp': 2
}
OAS_prob.add_surface(surf_dict)
OAS_prob.add_desvar('wing.twist_cp', lower=-15., upper=15.)
OAS_prob.add_desvar('wing.thickness_cp',
lower=0.01,
upper=0.5,
scaler=1e2)
OAS_prob.add_constraint('wing_perf.failure', upper=0.)
OAS_prob.add_constraint('wing_perf.thickness_intersects', upper=0.)
OAS_prob.add_desvar('alpha', lower=-10., upper=10.)
OAS_prob.add_constraint('eq_con', equals=0.)
OAS_prob.add_objective('fuelburn', scaler=1e-4)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['fuelburn'],
91972.867902621932,
places=0)
self.assertAlmostEqual(prob['wing_perf.failure'], 0, places=5)
def test_aero_viscous_chord_optimization(self):
# Need to use SLSQP here because SNOPT finds a different optimum
OAS_prob = OASProblem({
'type': 'aero',
'optimize': True,
'record_db': False,
'optimizer': 'SLSQP',
'with_viscous': True
})
OAS_prob.add_surface()
OAS_prob.add_desvar('wing.chord_cp', lower=0.1, upper=3.)
OAS_prob.add_desvar('alpha', lower=-10., upper=10.)
OAS_prob.add_constraint('wing_perf.CL', equals=0.5)
OAS_prob.add_constraint('wing.S_ref', equals=20)
OAS_prob.add_objective('wing_perf.CD', scaler=1e4)
OAS_prob.setup()
OAS_prob.run()
prob = OAS_prob.prob
self.assertAlmostEqual(prob['wing_perf.CD'],
0.023570021288019886,
places=5)
def driver(X):
assert len(
X[0]) == (2 * N_CP +
6), "Found dimension %d, expected %d" % (len(X[0]),
(2 * N_CP + 6))
# Set problem type
prob_dict = {
'type': 'aerostruct',
'optimize': False, # Don't optimize, only perform analysis
'record_db': False,
'W0':
1000., # OEW of the aircraft without fuel and the structural weight, in kg
}
# Instantiate problem and add default surface
with silence_stdout():
oas_prob = OASProblem(prob_dict)
# Create a dictionary to store options about the surface.
# Here we have 3 twist control points and 3 thickness control points.
# We also set the discretization, span, and panel spacing.
surf_dict = {
'name': 'wing',
'symmetry': True,
'num_y': 7,
'num_x': 2,
'span': 10.,
'num_twist_cp': N_CP,
'num_thickness_cp': N_CP,
'num_chord_cp': 2,
'wing_type': 'rect',
'span_cos_spacing': 0.,
}
# Add the specified wing surface to the problem
with silence_stdout():
oas_prob.add_surface(surf_dict)
# Set up the problem. Once we have this done, we can modify the internal
# unknowns and run the multidisciplinary analysis at that design point.
oas_prob.add_desvar('wing.twist_cp')
oas_prob.add_desvar('wing.thickness_cp')
oas_prob.add_desvar('wing.chord_cp')
oas_prob.setup(out_stream=null_stream)
Y = np.zeros((X.shape[0], 5))
for i, x in enumerate(tqdm(X)):
twist_cp = x[:N_CP]
thickness_cp = x[N_CP:2 * N_CP]
root_chord = x[2 * N_CP]
taper_ratio = x[2 * N_CP + 1]
alpha = x[2 * N_CP + 2]
E = x[2 * N_CP + 3]
G = x[2 * N_CP + 4]
mrho = x[2 * N_CP + 5]
oas_prob.surfaces[0]['E'] = E
oas_prob.surfaces[0]['G'] = G
oas_prob.surfaces[0]['mrho'] = mrho
with silence_stdout():
oas_prob.setup(out_stream=null_stream)
# set design variables
oas_prob.prob['alpha'] = alpha
oas_prob.prob['wing.twist_cp'] = twist_cp
oas_prob.prob['wing.thickness_cp'] = thickness_cp
oas_prob.prob['wing.chord_cp'] = np.array([taper_ratio, 1.
]) * root_chord
with silence_stdout():
oas_prob.run()
Y[i, 0] = oas_prob.prob['fuelburn']
Y[i, 1] = oas_prob.prob['wing_perf.structural_weight']
Y[i, 2] = oas_prob.prob['wing_perf.L']
Y[i, 3] = oas_prob.prob['total_weight']
Y[i, 4] = oas_prob.prob['wing_perf.failure']
return Y
'type': prob_type,
'compute_static_margin': True,
'optimizer': 'SNOPT',
'with_viscous': True,
'W0': 14., # kg, empty weight from manufacturer
'a': 322.2, # m/s, at 15,000 ft
'rho': 0.770816, # kg/m^3, at 15,000 ft
'R': 2500e3, # estimated range based on cruise speed and flight endurance
'CT': 9.80665 * 8.6e-6, # piston-prop estimation from Raymer
'Re': 4e5,
'M': .093, # calc'd from 30 m/s cruise speed
'cg': np.array([.4, 0., 0.]), # estimated based on aircraft pictures
}
# Instantiate problem and add default surface
OAS_prob = OASProblem(prob_dict)
zshear_cp = np.zeros(10)
zshear_cp[0] = .3
xshear_cp = np.zeros(10)
xshear_cp[0] = .15
chord_cp = np.ones(10)
chord_cp[0] = .5
radius_cp = 0.02 * np.ones(10)
radius_cp[0] = 0.015
if mesh_level == 'L1':
num_y = 101