I

100Cx

C_{x}=f(α)

I

C_z

Angle d'incidence α en degrés

C_{z}=g(α)

C_{x}

α

C_{z}

α

Coefficient \; de \; trainée

Coefficient  \; de \;  portance

Variations de type quadratique :
l'allure de la courbe est parabolique

Variations de type linéaire 
jusqu'à la perte de portance
et au décrochage

Angle d'incidence de l'aile en degrés

“ Polaire ” \; de \; l'aile

Il s'agit en fait de ce que les mathématiciens
appelent une “ courbe paramétrique ”
( C_x(α) ; C_z(α) )

Coefficient
de portance

Coefficient
de trainée

A2: -9
A3: -5.6
A4: -3.8
A5: -2.2
A6: -0.7
A7: 1
A8: 2.6
A9: 4.3
A10: 5.9
A11: 7.6
A12: 9
A13: 10.8
A14: 12.4
A15: 14.1
A16: 15.9
A17: 17.8
A18: 19.5
B2: 2.818
B3: 1.704
B4: 1.351
B5: 1
B6: 1.251
B7: 1.604
B8: 2.06
B9: 2.818
B10: 3.678
B11: 5.24
B12: 6.204
B13: 7.87
B14: 9.639
B15: 12.11
B16: 14.483
B17: 16.558
B18: 20.136
A: (A2, B2)
B: (A3, B3)
C: (A4, B4)
D: (A5, B5)
E: (A6, B6)
F: (A7, B7)
G: (A8, B8)
H: (A9, B9)
I: (A10, B10)
J: (A11, B11)
K: (A12, B12)
L: (A13, B13)
M: (A14, B14)
N: (A15, B15)
O: (A16, B16)
P: (A17, B17)
Q: (A18, B18)
L_1: {A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q}
C_x(x) = If[-9 < x < 25, FitPoly[L_1, 2]]
R = Point(C_x)
A20: -9
A21: -5.60000000000002
A22: -3.8
A23: -2.2
A24: -0.700000000000002
A25: 1
A26: 2.6
A27: 4.3
A28: 5.90000000000002
A29: 7.60000000000002
A30: 9
A31: 10.8
A32: 12.4
A33: 14.1
A34: 15.9
A35: 17.8
A36: 19.5
B20: -0.4
B21: -0.2
B22: -0.1
B23: 0
B24: 0.1
B25: 0.2
B26: 0.3
B27: 0.4
B28: 0.5
B29: 0.6
B30: 0.7
B31: 0.8
B32: 0.9
B33: 1
B34: 1.1
B35: 1.2
B36: 1.3
V = (5, -30)
f = OrthogonalLine(V, yAxis)
a = 11.9 (slider from -8.9 to 24.9, step 0.1)
Z: (a, C_x(a))
C20: (20 * B20) - 30
C21: (20 * B21) - 30
C22: (20 * B22) - 30
C23: (20 * B23) - 30
C24: (20 * B24) - 30
C25: (20 * B25) - 30
C26: (20 * B26) - 30
C27: (20 * B27) - 30
C28: (20 * B28) - 30
C29: (20 * B29) - 30
C30: (20 * B30) - 30
C31: (20 * B31) - 30
C32: (20 * B32) - 30
C33: (20 * B33) - 30
C34: (20 * B34) - 30
C35: (20 * B35) - 30
C36: (20 * B36) - 30
S: (A20, C20)
T: (A21, C21)
U: (A22, C22)
W: (A23, C23)
A_1: (A24, C24)
B_1: (A25, C25)
C_1: (A26, C26)
D_1: (A27, C27)
E_1: (A28, C28)
F_1: (A29, C29)
G_1: (A30, C30)
H_1: (A31, C31)
I_1: (A32, C32)
J_1: (A33, C33)
K_1: (A34, C34)
M_1: (A35, C35)
N_1: (A36, C36)
O_1 = (21.159121599406497, -3.2838639292497285)
P_1 = (22.748480002790565, -3.8476281382566424)
Q_1 = (23.904377023433522, -5.444960063776232)
R_1 = (24.84354335270593, -7.418134795300431)
S_1 = (25.638222554397963, -10.142995138833848)
L_2: {S, T, U, W, A_1, B_1, C_1, D_1, E_1, F_1, G_1, H_1, I_1, J_1, K_1, M_1, N_1, O_1, P_1, Q_1, R_1, S_1}
C_z(x) = If[-9 < x < 25, FitPoly[L_2, 6]]
g = OrthogonalLine(Z, xAxis)
T_1 = Intersect(C_z, g)
U_1 = Intersect(g, xAxis)
V_1 = Intersect(f, g)
h = Segment(Z, U_1)
i = Segment(T_1, V_1)
j = OrthogonalLine(Z, yAxis)
k = OrthogonalLine(T_1, yAxis)
W_1 = Intersect(j, yAxis)
Z_1 = Intersect(k, yAxis)
l = Segment(Z, W_1)
m = Segment(T_1, Z_1)
n = Segment(U_1, T_1)
b = CurveCartesian(C_x(u), (C_z(u) + 30) / 20, u, -9, 25)
Z': (y(Z), (y(T_1) + 30) / 20)
X: C_x(a)
Y: C_x(a) / 100
Δ: (C_z(a) + 30) / 20
texte6: "α=" + (LaTeX[a]) + "°"
p = OrthogonalLine(Z', yAxis)
q = OrthogonalLine(Z', xAxis)
A_2 = Intersect(yAxis, p)
B_2 = Intersect(q, xAxis)
r = Segment(Z', A_2)
s = Segment(Z', B_2)
C_2 = Point(f)
D_2 = Intersect(xAxis, yAxis)
u = Vector(C_2, D_2)
E_2 = Point(f)
v = Vector(C_2, E_2)
F_2 = Point(yAxis)
w = Vector(D_2, F_2)
G_2 = Point(xAxis)
c = Vector(D_2, G_2)
fin: Δ / Y
texte15: "Finesse \; : \; \frac{C_{z}}{C_{x}}=" + (LaTeX[fin]) + ""
t: y = 0
d: x = 0
f_1 = Derivative(C_x, x)
g_1 = Derivative(C_z, x)
vect: ((f_1(a) * 20), g_1(a))
Z_2: Z' + vect / 5
e = Line(Z', Z_2)
texte7: "" + (LaTeX[Δ]) + ""
texte8: "" + (LaTeX[Y]) + ""
texte2: "" + (LaTeX[Y]) + ""
texte5: "" + (LaTeX[Δ]) + ""
texte1: "" + (LaTeX[a]) + "°"
texte4: "" + (LaTeX[a]) + "°"