TIME-DOMAIN ANALYSIS OF LOW-SPEED AIRFOIL FLUTTER

A time-domain aeroelastic analysis code is described for single airfoi ls and two-foil systems in incompressible, inviscid flow Flow solution s are obtained using a time-stepping panel code, and airfoil motions a re computed using a two-degree-of-freedom spring/mass model, The time- stepping aeroelastic code is evaluated through comparisons with severa l classical frequency-domain studies for single-degree-of-freedom pitc hing motion. Results show excellent agreement with past studies and pr ovide a look into the evolution of the motion in time, Additionally, u sing a two-foil system, it is shown that flutter of a trailing airfoil can be controlled by proper oscillation and phasing of a leading airf oil, Three applications of the aeroelastic code are presented, includi ng a feedback loop to actively stabilize flutter of a trailing airfoil , simulations of wake interference in rotary-wing flowfields, and simu lations of flutter in ground effect.