Page 258 - Aerodynamics for Engineering Students

Finite wing theory 241

Fig. 5.30 Elliptic loading

Lift for elliptic distribution
From Eqn (5.34)

i.e.
S
L = pvTo7r- (5.38)
2
whence

or introducing
1
L = CL-pvZs
2

(5.39)

giving the mid-span circulation in terms of the overall aerofoil lift coefficient and
geometry.

Downwash for elliptic distribution
Here

Substituting this in Eqn (5.32)
z dz
wz, =
d G ( Z - z1)