"""Computation of Reynolds number"""
# This file is part of FAST-OAD_CS25
# Copyright (C) 2024 ONERA & ISAE-SUPAERO
# FAST is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
import fastoad.api as oad
import numpy as np
from openmdao.core.explicitcomponent import ExplicitComponent
from stdatm import AtmosphereSI
from ..constants import SERVICE_REYNOLDS_COEFFICIENT
[docs]
@oad.RegisterSubmodel(
SERVICE_REYNOLDS_COEFFICIENT,
"fastoad.submodel.aerodynamics.reynolds_coefficient.legacy",
)
class ComputeReynolds(ExplicitComponent):
"""Computation of Reynolds number"""
[docs]
def initialize(self):
self.options.declare("low_speed_aero", default=False, types=bool)
self.options.declare(
"altitude_var_name_high_speed",
default="data:mission:sizing:main_route:cruise:altitude_input",
types=str,
desc="Name of the variable to use for cruise altitude evaluation in Reynolds number "
"computation.",
)
[docs]
def setup(self):
if self.options["low_speed_aero"]:
self.add_input("data:aerodynamics:aircraft:takeoff:mach", val=np.nan, units="unitless")
self.add_output("data:aerodynamics:aircraft:low_speed:unit_reynolds", units="unitless")
else:
self.add_input("data:TLAR:cruise_mach", val=np.nan, units="unitless")
self.add_input(self.options["altitude_var_name_high_speed"], val=np.nan, units="m")
self.add_output("data:aerodynamics:aircraft:high_speed:unit_reynolds", units="unitless")
[docs]
def setup_partials(self):
self.declare_partials("*", "*", method="fd")
[docs]
def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
if self.options["low_speed_aero"]:
mach = inputs["data:aerodynamics:aircraft:takeoff:mach"]
altitude = 0.0
else:
mach = inputs["data:TLAR:cruise_mach"]
altitude = inputs[self.options["altitude_var_name_high_speed"]]
atm = AtmosphereSI(altitude)
atm.mach = mach
reynolds = atm.unitary_reynolds
if self.options["low_speed_aero"]:
outputs["data:aerodynamics:aircraft:low_speed:unit_reynolds"] = reynolds
else:
outputs["data:aerodynamics:aircraft:high_speed:unit_reynolds"] = reynolds