diff options
Diffstat (limited to 'evaluator.py')
| -rw-r--r-- | evaluator.py | 72 |
1 files changed, 44 insertions, 28 deletions
diff --git a/evaluator.py b/evaluator.py index 4ab9477..5710522 100644 --- a/evaluator.py +++ b/evaluator.py @@ -27,9 +27,12 @@ class Evaluator: def __init__(self, airfoil): # Evaluator knows all geometrical info from evaluated airfoil self.airfoil = airfoil + self.spar = airfoil.spar + self.stringer = airfoil.stringer # Global dimensions self.chord = airfoil.chord self.semi_span = airfoil.semi_span + # mass and area self.mass_total = float(airfoil.mass + airfoil.spar.mass @@ -41,11 +44,6 @@ class Evaluator: # Lower coordinates self.x_l = airfoil.x_l self.z_l = airfoil.z_l - # Spars - self.spar = airfoil.spar - # Stringers - self.stringer = airfoil.stringer - # Lifts self.lift_rectangular = [] self.lift_elliptical = [] self.lift_total = [] @@ -139,36 +137,52 @@ class Evaluator: def get_centroid(self): '''Return the coordinates of the centroid.''' - area = self.airfoil.stringer.area + stringer_area = self.stringer.area + caps_area = self.spar.cap_area - x_stringers = self.airfoil.stringer.x_u + self.airfoil.stringer.x_l - x_centroid = sum([x * area for x in x_stringers]) / \ - (len(x_stringers) * area) + x_spars = self.spar.x_u + self.spar.x_l + x_stringers = self.stringer.x_u + self.stringer.x_l + z_stringers = self.stringer.z_u + self.stringer.z_l + denom = float(len(x_spars) * caps_area + + len(x_stringers) * stringer_area) - z_stringers = self.airfoil.stringer.z_u + self.airfoil.stringer.z_l - z_centroid = sum([x * area for x in z_stringers]) / \ - (len(x_stringers) * area) - return(x_centroid, z_centroid) + x_ctr = (sum([i * caps_area for i in self.spar.x_u]) + + sum([i * stringer_area for i in x_stringers])) / denom + z_ctr = (sum([i * caps_area for i in self.spar.z_u]) + + sum([i * stringer_area for i in z_stringers])) / denom + return(x_ctr, z_ctr) def get_inertia_terms(self): '''Obtain all inertia terms.''' - area = self.stringer.area + stringer_area = self.stringer.area + caps_area = self.spar.cap_area + + # Adds upper and lower components' coordinates to list x_stringers = self.stringer.x_u + self.stringer.x_l z_stringers = self.stringer.z_u + self.stringer.z_l + x_spars = self.spar.x_u + self.spar.x_l + z_spars = self.spar.z_u + self.spar.z_l stringer_count = range(len(x_stringers)) - - # I_x is the sum of (stringer area * z-distance to the centroid) ** 2, - # for all stringers. - I_x = sum([area * (z_stringers[_] - self.centroid[1]) ** 2 - for _ in stringer_count]) - - I_z = sum([area * (x_stringers[_] - self.centroid[0]) ** 2 - for _ in stringer_count]) - - I_xz = sum([area * (z_stringers[_] - self.centroid[1]) - * (x_stringers[_] - self.centroid[0]) - for _ in stringer_count]) + spar_count = range(len(self.spar.x_u)) + + # I_x is the sum of the contributions of the spar caps and stringers + I_x = (sum([caps_area * (z_spars[i] - self.centroid[1]) ** 2 + for i in spar_count]) + + sum([stringer_area * (z_stringers[i] - self.centroid[1]) ** 2 + for i in stringer_count])) + + I_z = (sum([caps_area * (x_spars[i] - self.centroid[0]) ** 2 + for i in spar_count]) + + sum([stringer_area * (x_stringers[i] - self.centroid[0]) ** 2 + for i in stringer_count])) + + I_xz = (sum([caps_area * (x_spars[i] - self.centroid[0]) + * (z_spars[i] - self.centroid[1]) + for i in spar_count]) + + sum([stringer_area * (x_stringers[i] - self.centroid[0]) + * (z_stringers[i] - self.centroid[1]) + for i in stringer_count])) return(I_x, I_z, I_xz) @@ -245,8 +259,10 @@ def plot_lift(evaluator): y_1 = evaluator.lift_rectangular y_2 = evaluator.lift_elliptical y_3 = evaluator.lift_total - plt.plot(x, y_1, '.', color='b', markersize=4, label='Rectangular lift') - plt.plot(x, y_2, '.', color='g', markersize=4, label='Elliptical lift') + plt.plot(x, y_1, '.', color='b', markersize=4, + label='Rectangular lift') + plt.plot(x, y_2, '.', color='g', markersize=4, + label='Elliptical lift') plt.plot(x, y_3, '.', color='r', markersize=4, label='Total lift') # Graph formatting |