import numpy as np
import openmdao.api as om
from openaerostruct.structures.utils import radii
[docs]
class SparWithinWing(om.ExplicitComponent):
"""
Create a constraint to see if the spar is within the wing.
This is based on the wing's t/c and the spar radius.
.. warning::
This component has not been extensively tested.
It may require additional coding to work as intended.
parameters
----------
mesh[nx, ny, 3] : numpy array
Array defining the nodal points of the lifting surface.
radius[ny-1] : numpy array
Radius of each element of the FEM spar.
t_over_c[ny-1] : numpy array
The streamwise thickness-to-chord ratio of each VLM panel.
Returns
-------
spar_within_wing[ny-1] : numpy array
If all the values are negative, each element is within the wing,
based on the surface's t_over_c value and the current chord.
Set a constraint with
`OASProblem.add_constraint('spar_within_wing', upper=0.)`
"""
def initialize(self):
self.options.declare("surface", types=dict)
def setup(self):
self.surface = surface = self.options["surface"]
self.ny = surface["mesh"].shape[1]
nx = surface["mesh"].shape[0]
self.add_input("mesh", val=np.zeros((nx, self.ny, 3)), units="m")
self.add_input("radius", val=np.zeros((self.ny - 1)), units="m")
self.add_input("t_over_c", val=np.zeros((self.ny - 1)))
self.add_output("spar_within_wing", val=np.zeros((self.ny - 1)), units="m")
self.declare_partials("spar_within_wing", "mesh", method="cs")
arange = np.arange(self.ny - 1)
self.declare_partials("spar_within_wing", "radius", rows=arange, cols=arange, val=1.0)
def compute(self, inputs, outputs):
mesh = inputs["mesh"]
t_over_c = inputs["t_over_c"]
max_radius = radii(mesh, t_over_c)
outputs["spar_within_wing"] = inputs["radius"] - max_radius