"""
Python module for total aircraft wet area calculation, part of the geometry component.
"""
# This file is part of FAST-OAD_CS23 : A framework for rapid Overall Aircraft Design
# Copyright (C) 2025 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 numpy as np
import openmdao.api as om
import fastoad.api as oad
from ..constants import SERVICE_AIRCRAFT_WET_AREA, SUBMODEL_AIRCRAFT_WET_AREA_LEGACY
[docs]@oad.RegisterSubmodel(SERVICE_AIRCRAFT_WET_AREA, SUBMODEL_AIRCRAFT_WET_AREA_LEGACY)
class ComputeTotalArea(om.ExplicitComponent):
"""Total aircraft wet area estimation, obtained from :cite:`supaero:2014`."""
# pylint: disable=missing-function-docstring
# Overriding OpenMDAO setup
[docs] def setup(self):
self.add_input("data:geometry:wing:wet_area", val=np.nan, units="m**2")
self.add_input("data:geometry:fuselage:wet_area", val=np.nan, units="m**2")
self.add_input("data:geometry:horizontal_tail:wet_area", val=np.nan, units="m**2")
self.add_input("data:geometry:vertical_tail:wet_area", val=np.nan, units="m**2")
self.add_input("data:geometry:propulsion:nacelle:wet_area", val=np.nan, units="m**2")
self.add_input("data:geometry:propulsion:engine:count", val=np.nan)
self.add_output("data:geometry:aircraft:wet_area", units="m**2")
self.declare_partials(
"*",
[
"data:geometry:wing:wet_area",
"data:geometry:fuselage:wet_area",
"data:geometry:horizontal_tail:wet_area",
"data:geometry:vertical_tail:wet_area",
],
val=1.0,
)
self.declare_partials(
"*",
["data:geometry:propulsion:nacelle:wet_area", "data:geometry:propulsion:engine:count"],
method="exact",
)
# pylint: disable=missing-function-docstring, unused-argument
# Overriding OpenMDAO compute, not all arguments are used
[docs] def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
wet_area_wing = inputs["data:geometry:wing:wet_area"]
wet_area_fus = inputs["data:geometry:fuselage:wet_area"]
wet_area_ht = inputs["data:geometry:horizontal_tail:wet_area"]
wet_area_vt = inputs["data:geometry:vertical_tail:wet_area"]
wet_area_nac = inputs["data:geometry:propulsion:nacelle:wet_area"]
nacelle_nb = inputs["data:geometry:propulsion:engine:count"]
wet_area_total = (
wet_area_wing + wet_area_fus + wet_area_ht + wet_area_vt + nacelle_nb * wet_area_nac
)
outputs["data:geometry:aircraft:wet_area"] = wet_area_total
# pylint: disable=missing-function-docstring, unused-argument
# Overriding OpenMDAO compute_partials, not all arguments are used
[docs] def compute_partials(self, inputs, partials, discrete_inputs=None):
wet_area_nac = inputs["data:geometry:propulsion:nacelle:wet_area"]
nacelle_nb = inputs["data:geometry:propulsion:engine:count"]
partials["data:geometry:aircraft:wet_area", "data:geometry:propulsion:nacelle:wet_area"] = (
nacelle_nb
)
partials["data:geometry:aircraft:wet_area", "data:geometry:propulsion:engine:count"] = (
wet_area_nac
)