Supersonic Linearized Theory (Mo > 1)

The wave drag coefficient (Cd)a=0 is given by

dx 16 ґв[8]

c 3в Vc/

(Cd )a=0 = (f’+(X )f + (f ‘-(X ))"

as seen in class.

Hence the lift and wave drag coefficients are:

4a

Cl (a) = — = 0.0403

P

16 /e2 4a2

Cd(a) = 3в U + IT = a0315

3в c) в

The lift and wave drag upper bounds for the fin are

12

L = 2 pV[9] 2bc Cl = 106 N

D = 2pV2bc Cd = 82.9 N

15.3.1 Lifting Line Theory (3-D Inviscid Flow)

15.3.2.1 Induced Drag in Cruise The induced drag Di in (N) is given by

1 2 c2l

Di = – pV 2 5—– —

i Г neAR

1 1 pV2neb2

Подпись: Elimination of CL yields: Подпись: Di Подпись: W2

The equilibrium equation along the vertical axis during horizontal cruise in dimen­sional form (neglecting the lift of the tail) reads:

Supersonic Linearized Theory (Mo > 1)
Подпись: 2

The drag penalty is = 0.21, i. e. a 21 % increase in induced drag.