def cross_reference(self, model: BDF) -> None:
"""
Cross links the card so referenced cards can be extracted directly
Parameters
----------
model : BDF()
the BDF object
"""
msg = ', which is required by FLUTTER sid=%s' % self.sid
self.density_ref = model.FLFACT(self.density, msg=msg)
self.mach_ref = model.FLFACT(self.mach, msg=msg)
self.reduced_freq_velocity_ref = model.FLFACT(self.reduced_freq_velocity, msg=msg)
def test_flutter(self):
"""checks the FLUTTER/FLFACT cards"""
log = SimpleLogger(level='warning')
model = BDF(log=log)
sid = 75
method = 'PKNL'
idensity = 76
imach = 77
ivelocity = 78
# density, mach, velocity
flutter1 = FLUTTER(sid, method, idensity, imach, ivelocity)
flutter2 = FLUTTER.add_card(BDFCard(['FLUTTER', sid, method, idensity, imach,
ivelocity]), comment='flutter card')
assert flutter2.headers == ['density', 'mach', 'velocity'], flutter2.headers
flutter1.validate()
flutter1.write_card()
flutter2.validate()
flutter2.write_card()
model.flutters[75] = flutter1
densities = np.linspace(0., 1.)
density = FLFACT(idensity, densities)
model.flfacts[idensity] = density
machs = np.linspace(0.7, 0.8)
mach = FLFACT(imach, machs)
mach = FLFACT.add_card(BDFCard(['FLFACT', imach] + list(machs)), comment='flfact card')
mach.write_card(size=16)
model.flfacts[imach] = mach
velocities = np.linspace(3., 4.)
velocity = FLFACT(ivelocity, velocities)
velocity.validate()
velocity.write_card()
assert velocity.min() == 3., velocities
assert velocity.max() == 4., velocities
model.flfacts[ivelocity] = velocity
ikfreq = 79
kfreqs = np.linspace(0.1, 0.2)
card = ['FLFACT', ikfreq] + list(kfreqs)
model.add_card(card, card[0])
kfreq = model.FLFACT(ikfreq)
kfreq.validate()
kfreq.write_card()
assert kfreq.min() == 0.1, kfreqs
assert kfreq.max() == 0.2, kfreqs
model.flfacts[ikfreq] = kfreq
ikfreq2 = 80
card = ['FLFACT', ikfreq2, 10., 'THRU', 20., 11]
model.add_card(card, card[0])
kfreq = model.FLFACT(ikfreq2)
kfreq.validate()
kfreq.write_card()
assert kfreq.min() == 10., 'min=%s; card=%s factors=%s' % (kfreq.min(), card, kfreq.factors)
assert kfreq.max() == 20., 'max=%s; card=%s factors=%s' % (kfreq.max(), card, kfreq.factors)
model.flfacts[ikfreq] = kfreq
ikfreq3 = 81
factors = [10., 'THRU', 20., 10]
kfreq = FLFACT(ikfreq3, factors)
kfreq.validate()
kfreq.write_card()
assert kfreq.min() == 10., 'min=%s; factors=%s' % (kfreq.min(), factors)
assert kfreq.max() == 20., 'max=%s; factors=%s' % (kfreq.max(), factors)
model.flfacts[ikfreq] = kfreq
# density, mach, rfreq
card = ['FLUTTER', 85, 'KE', idensity, imach, ikfreq]
model.add_card(card, card[0])
model.cross_reference()
flutter = model.Flutter(85)
assert flutter.headers == ['density', 'mach', 'reduced_frequency'], flutter.headers
flutter.write_card()
