utils module

utils.add_minimum_gap(xy)

Adding minimum TE gap of 2mm. Before using need to position airfoil first (chord on x-axis from 0 to 1)

Parameters:

xy – (n, 2)shape coordinates

Returns:

array of shape coordinates with added gap

utils.add_tailedge_gap(xy, gap)

Adding tail edge gap. Before using need to position airfoil first (chord on x-axis from 0 to 1)

Parameters:

• xy – (n, 2) shape coordinate

• gap – gap size to be added

Returns:

array of shape coordinates with added gap

utils.arc_distance(xy)

Calculate distance along the arc of points defining airfoil shape. t in [0, 1]

Parameters:

xy – (n_landmarks, 2) discrete planar curve with n landmarks representing a shape

Returns:

(n_landmarks, ) distance along the arc of points defining airfoil shape

utils.calc_area(xy, a=0, b=1)

Function calculates area inside of an airfoil shape xy (x coordinates are normalized by chord length) from left boundary a to right boundary b using discrete representation of a shape and trapesoidal rule.

E.g. to calculate area inside of an airfoil from 25% chord to 45% chord one can use calc_area(xy, a=0.25, b=0.45)

Parameters:

• xy – (n, 2) array of given shape

• a – left boundary

• b – right boundary

Returns:

scalar area

utils.calc_curvature(xy)

Calculate curvature based on planar respresentation.

Parameters:

xy – (n_landmarks, 2) discrete planar curve with n landmarks representing a shape

Returns:

curvature values

utils.calc_curvature_at_x(xy)

Calculate curvature based on planar respresentation.

Parameters:

xy – (n_landmarks, 2) discrete planar curve with n landmarks representing a shape

Returns:

curvature values

utils.calc_unit_normal(shape)

utils.check_selfintersect(shape)

Check if self intersection in a shape exist.

Parameters:

X – (n_landmarks, 2) discrete planar curve with n landmarks representing a shape

Returns:

bool = if intersection exist

utils.find_selfintersect(shape)

Find all self intersections of shape.

Parameters:

X – (n_landmarks, 2) discrete planar curve with n landmarks representing a shape

Returns:

bool = if intersection exist (n, 2) array with index p and q of intersecting intervals (n=number of intersections) (n, 2) array of intersection locations (n=number of intersections)

utils.position_airfoil(shape_inp, rotate=True, LE_cst=False, return_LEind=False)

Normalize, rotates and translates given airfoil coordinates so that the leading edge is at (0, 0) and tail edge is at (1, 0).

Parameters:

• shape_inp – (n, 2) shape coordinates

• rotate – (bool) rotate airfoil to set LE at (0,0), defaults to True

• LE_cst – (bool) set true if shape_inp is from CST parametrization to use x=0 point as LE, defaults to False

• return_LEind – (bool) return index of leading edge coordinate, defaults to False

Returns:

array of shape coordinates

utils.remove_tailedge_gap(xy)

Remove tailedge gap.

Parameters:

xy – (n, 2) shape coordinates

Returns:

array of shape coordinates without gap

utils.tailedge_gap(xy)

Calculate tail edge gap size

:param xy (n, 2) shape coordinates :return: TE gap size