100
P. Liu
Fig. 2.31 Trailing edge conditions around steady airfoil
we get
δ u (b)
0
V u
δ u (b)
dy ≈
δ d (b)
0
V d
δ d (b)
dy,V u ≈ V d
This is the condition of Kutta and Joukowsky at the trailing edge,
namely, the condition of leaving trailing edge smoothly is that the velocity
of upper and lower wing surfaces leaving trailing edge is approximately
equal. If you do the following
γ 0 =
δ u (b)
0
2ω u dy
=
C
V • d s =
b
0
[γ u − γ d ]dx =
b
0
[γ u − γ 0 ]dx
+
b
0
[γ 0 − γ d ]dx = u + d
L = ρV ∞ u + ρV ∞ d
the contribution of the upper and lower wings to the lift can be obtained.
As shown in Fig. 2.32, at low angle of attack, the calculation formula of
lift coefficient based on the pressure coefficient distribution acting on the
P. Liu
Fig. 2.31 Trailing edge conditions around steady airfoil
we get
δ u (b)
0
V u
δ u (b)
dy ≈
δ d (b)
0
V d
δ d (b)
dy,V u ≈ V d
This is the condition of Kutta and Joukowsky at the trailing edge,
namely, the condition of leaving trailing edge smoothly is that the velocity
of upper and lower wing surfaces leaving trailing edge is approximately
equal. If you do the following
γ 0 =
δ u (b)
0
2ω u dy
=
C
V • d s =
b
0
[γ u − γ d ]dx =
b
0
[γ u − γ 0 ]dx
+
b
0
[γ 0 − γ d ]dx = u + d
L = ρV ∞ u + ρV ∞ d
the contribution of the upper and lower wings to the lift can be obtained.
As shown in Fig. 2.32, at low angle of attack, the calculation formula of
lift coefficient based on the pressure coefficient distribution acting on the