def test_drag(self):
n = 10
p = om.Problem()
tas_kt = np.linspace(0, 100, n) * 1.94384
mass = 200000
flap_angle = 10
path_angle = 0
alt = 0
ivc = p.model.add_subsystem('ivc',
subsys=om.IndepVarComp(),
promotes_outputs=['*'])
ivc.add_output(name='tas', val=tas_kt, units='kn')
ivc.add_output(name='mass', val=mass, units='kg')
ivc.add_output(name='flap_angle', val=flap_angle, units='deg')
ivc.add_output(name='alt', val=alt, units='m')
ivc.add_output(name='grav', val=9.80665, units='m/s**2')
p.model.add_subsystem('atmos', subsys=USatm1976Comp(num_nodes=1))
p.model.add_subsystem(
'cl_comp',
subsys=om.ExecComp(
'CL=(mass * grav * np.cos(flight_path))/(qbar * S)',
mass={
'value': 0.0,
'units': 'kg'
},
grav={
'value': 0.0,
'units': 'm/s**2'
},
flight_path={
'value': 0.0,
'units': 'rad'
},
qbar={
'value': np.repeat(0.0, n),
'units': 'Pa'
},
S={
'value': 0.0,
'units': 'm**2'
},
cl={
'value': np.repeat(0.0, n),
'units': 'None'
}))
p.model.add_subsystem('aero',
subsys=AerodynamicsGroup(num_nodes=n,
airplane_data=b747))
p.model.connect('tas', 'aero.tas')
p.model.connect('alt', 'atmos.h')
p.model.connect('atmos.rho', 'aero.rho')
p.model.connect('flap_angle', 'aero.flap_angle')
p.model.connect('aero.qbar', 'cl_comp.qbar')
p.model.connect('mass', ['aero.mass', 'cl_comp.mass'])
p.model.connect('grav', ['aero.grav', 'cl_comp.grav'])
p.model.connect('aero.coeff_comp.CL', 'cl_comp.CL')
p.model.connect('cl_comp.CL', 'aero.coeff_comp.CL')
p.setup()
p.set_val('cl_comp.S', b747.wing.area)
p.set_val('cl_comp.flight_path', path_angle)
p.run_model()
print(p.get_val('aero.D'))
drag = Drag(ac='B744')
reference_drag = [
drag.nonclean(mass=mass,
tas=v,
alt=alt,
flap_angle=flap_angle,
path_angle=path_angle,
landing_gear=True) for v in tas_kt
]
print(reference_drag)
assert_near_equal(p.get_val('aero.D'), reference_drag)
drag = Drag(ac='A320')
print('-'*70)
D = drag.clean(mass=60000, tas=200, alt=20000)
print("drag.clean(mass=60000, tas=200, alt=20000)")
print(D)
print('-'*70)
D = drag.clean(mass=60000, tas=250, alt=20000)
print("drag.clean(mass=60000, tas=250, alt=20000)")
print(D)
print('-'*70)
D = drag.nonclean(mass=60000, tas=150, alt=1000, flap_angle=20, path_angle=10, landing_gear=False)
print("drag.nonclean(mass=60000, tas=150, alt=1000, flap_angle=20, path_angle=10, landing_gear=False)")
print(D)
print('-'*70)
D = drag.nonclean(mass=60000, tas=150, alt=200, flap_angle=20, path_angle=10, landing_gear=True)
print("drag.nonclean(mass=60000, tas=150, alt=1000, flap_angle=20, path_angle=10, landing_gear=True)")
print(D)
print('-'*70)
D = drag.clean(mass=[60000], tas=[200], alt=[20000])
print("drag.clean(mass=[60000], tas=[200], alt=[20000])")
print(D)
print('-'*70)