def branch(n):
n1 = np.copy(n)
n2 = np.copy(n)
for i in range(len(n)):
if n[i] == None:
n1[i] = 0
n2[i] = 1
return n1, n2
def rotate(self,
angle: float,
x_center: float = 0.,
y_center: float = 0.) -> 'Airfoil':
"""
Rotates the airfoil clockwise by the specified amount, in radians.
Rotates about the point (x_center, y_center), which is (0, 0) by default.
Args:
angle: Angle to rotate, counterclockwise, in radians.
x_center: The x-coordinate of the center of rotation.
y_center: The y-coordinate of the center of rotation.
Returns: The rotated Airfoil.
"""
coordinates = np.copy(self.coordinates)
### Translate
translation = np.array([x_center, y_center])
coordinates -= translation
### Rotate
rotation_matrix = np.rotation_matrix_2D(angle=angle, )
coordinates = (rotation_matrix @ coordinates.T).T
### Translate
coordinates += translation
return Airfoil(name=self.name, coordinates=coordinates)
def add_control_surface(
self,
deflection: float = 0.,
hinge_point_x: float = 0.75,
) -> 'Airfoil':
"""
Returns a version of the airfoil with a control surface added at a given point. Implicitly repanels the airfoil as part of this operation.
:param deflection: deflection angle [degrees]. Downwards-positive.
:param hinge_point_x: location of the hinge, as a fraction of chord [float].
:return: The new airfoil.
"""
# Make the rotation matrix for the given angle.
rotation_matrix = np.rotations.rotation_matrix_2D(-np.pi / 180 *
deflection)
# Find the hinge point
hinge_point_y = self.local_camber(hinge_point_x)
# Find the coordinates of a rotated airfoil
rotated_airfoil = self.rotate(
angle=-np.pi / 180 * deflection,
x_center=hinge_point_x,
y_center=hinge_point_y,
)
# Merge the two sets of coordinates
coordinates = np.copy(self.coordinates)
is_past_hinge = self.x(
) > hinge_point_x # TODO fix hinge self-intersecting paneling issue for large deflection
coordinates[is_past_hinge] = rotated_airfoil.coordinates[is_past_hinge]
return Airfoil(name=self.name, coordinates=coordinates)