"""
Computation of wing area
"""
# 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
import openmdao.api as om
from fastoad.module_management.constants import ModelDomain
from .constants import (
SERVICE_WING_AREA_CONSTRAINT_AERO,
SERVICE_WING_AREA_CONSTRAINT_GEOM,
SERVICE_WING_AREA_LOOP_AERO,
SERVICE_WING_AREA_LOOP_GEOM,
)
[docs]
@oad.RegisterOpenMDAOSystem("fastoad.loop.wing_area", domain=ModelDomain.OTHER)
class ComputeWingArea(om.Group):
"""
Computes needed wing area for:
- having enough lift at required approach speed
- being able to load enough fuel to achieve the sizing mission
"""
[docs]
def initialize(self):
super().initialize()
self.options.declare("use_fuel", default=True, types=bool)
self.options.declare("use_approach_speed", default=True, types=bool)
[docs]
def setup(self):
if self.options["use_fuel"]:
self.add_subsystem(
"wing_area_geom",
oad.RegisterSubmodel.get_submodel(SERVICE_WING_AREA_LOOP_GEOM),
promotes_inputs=["*"],
promotes_outputs=[],
)
self.connect("wing_area_geom.wing_area:geom", "wing_area.wing_area:geom")
if self.options["use_approach_speed"]:
self.add_subsystem(
"wing_area_aero",
oad.RegisterSubmodel.get_submodel(SERVICE_WING_AREA_LOOP_AERO),
promotes_inputs=["*"],
promotes_outputs=[],
)
self.connect("wing_area_aero.wing_area:aero", "wing_area.wing_area:aero")
if self.options["use_fuel"] or self.options["use_approach_speed"]:
self.add_subsystem(
"wing_area",
_ComputeWingArea(),
promotes_inputs=[],
promotes_outputs=["*"],
)
self.add_subsystem(
"geom_constraint",
oad.RegisterSubmodel.get_submodel(SERVICE_WING_AREA_CONSTRAINT_GEOM),
promotes=["*"],
)
self.add_subsystem(
"aero_constraint",
oad.RegisterSubmodel.get_submodel(SERVICE_WING_AREA_CONSTRAINT_AERO),
promotes=["*"],
)
class _ComputeWingArea(om.ExplicitComponent):
"""
Computation of wing area from needed approach speed and mission fuel and taking whichever
is greatest
"""
def setup(self):
self.add_input("wing_area:aero", units="m**2", val=0.0)
self.add_input("wing_area:geom", units="m**2", val=0.0)
self.add_output("data:geometry:wing:area", val=100.0, units="m**2")
self.declare_partials(of="*", wrt="*", method="exact")
def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
wing_area_mission = inputs["wing_area:geom"]
wing_area_approach = inputs["wing_area:aero"]
outputs["data:geometry:wing:area"] = np.nanmax([wing_area_mission, wing_area_approach])
def compute_partials(self, inputs, partials, discrete_inputs=None):
wing_area_mission = inputs["wing_area:geom"]
wing_area_approach = inputs["wing_area:aero"]
partials["data:geometry:wing:area", "wing_area:geom"] = (
1.0 if wing_area_mission > wing_area_approach else 0.0
)
partials["data:geometry:wing:area", "wing_area:aero"] = (
0.0 if wing_area_mission > wing_area_approach else 1.0
)