Time-domain analysis of low-speed airfoil flutter

A time-domain aeroelastic analysis code is described for single airfoils and two-foil systems in incompressible, inviscid flow Flow solutions are obtained using a time-stepping panel code, and airfoil motions are computed using a two-degree-of-freedom spring/mass model, The time-stepping aeroelastic code is evaluated through comparisons with several classical frequency-domain studies for single-degree-of-freedom pitching motion. Results show excellent agreement with past studies and provide a look into the evolution of the motion in time, Additionally, using a two-foil system, it is shown that flutter of a trailing airfoil can be controlled by proper oscillation and phasing of a leading airfoil, Three applications of the aeroelastic code are presented, including a feedback loop to actively stabilize flutter of a trailing airfoil, simulations of wake interference in rotary-wing flowfields, and simulations of flutter in ground effect.