Linear Unsteady Aerodynamic Models from Wind Tunnel Measurements
نویسندگان
چکیده
Linear unsteady aerodynamic models are obtained for a NACA 0006 airfoil in a wind tunnel experiment at Reynolds number 65,000. A family of system identification maneuvers, based on a canonical step-up, hold maneuver, are specifically designed to extract relevant unsteady information from phase averaged wind tunnel measurements. Linear models based on these maneuvers are constructed using OKID/ERA for the case of pitching about α0 = 0 ◦ and α0 = 10 ◦, as well as the case of pure plunge. It is shown that the identified models are more accurate than Theodorsen’s model for all maneuvers, especially those at larger base angle of attack.
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