What are the values of the feathering parameters for the airfoils given by Examples 8.5 and 8.6?

Examples 8.5

Assume an airfoil pitching about its leading edge and plunging with \(k=0.35\) as follows

\[
\begin{aligned}
& h=1.1 \cos (\omega t) \\
& \alpha=10^{\circ}+10^{\circ} \cos (\omega t+\pi / 2)
\end{aligned}
\]

Examples 8.6

The NACA 0012 airfoil is pitching and plunging with a reduced frequency of 1 as given below

\[
\begin{aligned}
& h=0.65 \cos (\omega t) \\
& \alpha=20^{\circ}+20^{\circ} \cos (\omega t+\pi / 2)
\end{aligned}
\]

Show that the effective angle of attack remains under the dynamic separation angle of attack.

Transcribed Image Text:

2 h* nid n Difference (%) (Ref) (%) 0.45 73 58.5 20 15.4 82.4 0.57 79 63.8 20 21 86.7