Experimnetal Investigations of the Lift Frequency Response at High Angels of Attack

In comparison to the numerous theoretical research reports on the unsteady nonlinear aerodynamics, there has been very few experimental data available for validation purposes; particularly, at high angles of attack (40◦ and higher). We perform experiments on an oscillating two-dimensional NACA 0012 airfoil at various reduced frequencies (0.1 ≤ k ≤ 0.9) and mean angles of attack (0◦ ≤ α0 ≤ 65◦) that undergoes a plunging motion. For each case of the mean angle of attack, the plunging motion is performed with a small amplitude at different frequencies to determine the frequency response of the dynamics. The objective is to assess the effects of the mean angle of attack on the flow dynamics and determine specific aspects associated with unsteady motions at high values of the angle of attack and the reduced frequency.