"""
Estimation of vertical tail chords and span
"""
# This file is part of FAST-OAD : A framework for rapid Overall Aircraft Design
# Copyright (C) 2021 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
from openmdao.core.explicitcomponent import ExplicitComponent
[docs]class ComputeVTChords(ExplicitComponent):
# TODO: Document equations. Cite sources
""" Vertical tail chords and span estimation """
[docs] def setup(self):
self.add_input("data:geometry:vertical_tail:aspect_ratio", val=np.nan)
self.add_input("data:geometry:vertical_tail:area", val=np.nan, units="m**2")
self.add_input("data:geometry:vertical_tail:taper_ratio", val=np.nan)
self.add_output("data:geometry:vertical_tail:span", units="m")
self.add_output("data:geometry:vertical_tail:root:chord", units="m")
self.add_output("data:geometry:vertical_tail:tip:chord", units="m")
[docs] def setup_partials(self):
self.declare_partials(
"data:geometry:vertical_tail:span",
["data:geometry:vertical_tail:aspect_ratio", "data:geometry:vertical_tail:area"],
method="fd",
)
self.declare_partials("data:geometry:vertical_tail:root:chord", "*", method="fd")
self.declare_partials("data:geometry:vertical_tail:tip:chord", "*", method="fd")
[docs] def compute(self, inputs, outputs):
lambda_vt = inputs["data:geometry:vertical_tail:aspect_ratio"]
s_v = inputs["data:geometry:vertical_tail:area"]
taper_v = inputs["data:geometry:vertical_tail:taper_ratio"]
b_v = np.sqrt(max(lambda_vt * s_v, 0.1)) #
root_chord = s_v * 2 / (1 + taper_v) / b_v
tip_chord = root_chord * taper_v
outputs["data:geometry:vertical_tail:span"] = b_v
outputs["data:geometry:vertical_tail:root:chord"] = root_chord
outputs["data:geometry:vertical_tail:tip:chord"] = tip_chord