# This file is part of FAST-OAD_CS23 : A framework for rapid Overall Aircraft Design
# Copyright (C) 2022 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
[docs]class ReserveEnergy(om.ExplicitComponent):
"""Computes the fuel consumed during the reserve phase."""
[docs] def setup(self):
self.add_input("data:mission:sizing:main_route:cruise:fuel", np.nan, units="kg")
self.add_input("data:mission:sizing:main_route:cruise:energy", np.nan, units="W*h")
self.add_input("data:mission:sizing:main_route:cruise:duration", np.nan, units="s")
self.add_input("data:mission:sizing:main_route:reserve:duration", np.nan, units="s")
self.add_input("settings:mission:sizing:main_route:reserve:k_factor", val=1.0)
self.add_output("data:mission:sizing:main_route:reserve:fuel", units="kg")
self.add_output("data:mission:sizing:main_route:reserve:energy", units="W*h")
[docs] def setup_partials(self):
self.declare_partials(
of="data:mission:sizing:main_route:reserve:fuel",
wrt=[
"data:mission:sizing:main_route:cruise:fuel",
"data:mission:sizing:main_route:cruise:duration",
"data:mission:sizing:main_route:reserve:duration",
"settings:mission:sizing:main_route:reserve:k_factor",
],
method="exact",
)
self.declare_partials(
of="data:mission:sizing:main_route:reserve:energy",
wrt=[
"data:mission:sizing:main_route:cruise:energy",
"data:mission:sizing:main_route:cruise:duration",
"data:mission:sizing:main_route:reserve:duration",
"settings:mission:sizing:main_route:reserve:k_factor",
],
method="exact",
)
[docs] def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
m_reserve = (
inputs["data:mission:sizing:main_route:cruise:fuel"]
* inputs["data:mission:sizing:main_route:reserve:duration"]
* inputs["settings:mission:sizing:main_route:reserve:k_factor"]
/ max(
1e-6, inputs["data:mission:sizing:main_route:cruise:duration"]
) # avoid 0 division
)
energy_reserve = (
inputs["data:mission:sizing:main_route:cruise:energy"]
* inputs["data:mission:sizing:main_route:reserve:duration"]
* inputs["settings:mission:sizing:main_route:reserve:k_factor"]
/ max(
1e-6, inputs["data:mission:sizing:main_route:cruise:duration"]
) # avoid 0 division
)
outputs["data:mission:sizing:main_route:reserve:fuel"] = m_reserve
outputs["data:mission:sizing:main_route:reserve:energy"] = energy_reserve
[docs] def compute_partials(self, inputs, partials, discrete_inputs=None):
cruise_time = inputs["data:mission:sizing:main_route:cruise:duration"]
rsv_time = inputs["data:mission:sizing:main_route:reserve:duration"]
cruise_fuel = inputs["data:mission:sizing:main_route:cruise:fuel"]
cruise_energy = inputs["data:mission:sizing:main_route:cruise:energy"]
k_factor = inputs["settings:mission:sizing:main_route:reserve:k_factor"]
partials[
"data:mission:sizing:main_route:reserve:fuel",
"data:mission:sizing:main_route:cruise:fuel",
] = rsv_time * k_factor / cruise_time
partials[
"data:mission:sizing:main_route:reserve:energy",
"data:mission:sizing:main_route:cruise:energy",
] = rsv_time * k_factor / cruise_time
partials[
"data:mission:sizing:main_route:reserve:fuel",
"data:mission:sizing:main_route:reserve:duration",
] = cruise_fuel * k_factor / cruise_time
partials[
"data:mission:sizing:main_route:reserve:energy",
"data:mission:sizing:main_route:reserve:duration",
] = cruise_energy * k_factor / cruise_time
partials[
"data:mission:sizing:main_route:reserve:fuel",
"data:mission:sizing:main_route:cruise:duration",
] = rsv_time * cruise_fuel * k_factor / cruise_time**2
partials[
"data:mission:sizing:main_route:reserve:energy",
"data:mission:sizing:main_route:cruise:duration",
] = rsv_time * cruise_energy * k_factor / cruise_time**2