Nonlinear aerodynamics of two-dimensional airfoils in severe maneuver

Results are obtained for cases of both large and small amplitude motion. The analysis, which is based in part on an extension of Wagner's integral equation to the nonlinear regime, allows completely for the trailing wake's tendency to deform under local velocities. Interactive computational results are presented for a variety of imposed airfoil motions. These show examples of wake-induced lift and moment augmentation and/or delay on the order of 20-30 percent of quasistatic values as well as a variety of long-term «history» effects

[1]  Herbert Wagner.  Über die Entstehung des dynamischen Auftriebes von Tragflügeln , 1925 .

[2]  T. Theodorsen.  General Theory of Aerodynamic Instability and the Mechanism of Flutter , 1934 .

[3]  O. Tietjens,et al.  Fundamentals of hydro- and aeromechanics , 1934 .

[4]  T. Kármán,et al.  Airfoil Theory for Non-Uniform Motion , 1938 .

[5]  W. Sears,et al.  Some Aspects of Non-Stationary Airfoil Theory and Its Practical Application , 1941 .

[6]  Joseph Katz,et al.  Behavior of Vortex Wakes from Oscillating Airfoils , 1978 .

[7]  Joseph Katz,et al.  Wake Rollup and the Kutta Condition for Airfoils Oscillating at High Frequency , 1981 .

[8]  Joseph Katz,et al.  Vortex-Lattice Method for the Calculation of the Nonsteady Separated Flow over Delta Wings , 1981 .

[9]  M. V. Dyke,et al.  An Album of Fluid Motion , 1982 .

[10]  P. Stremel.  A method for modeling finite-core vortices in wake-flow calculations , 1984 .

[11]  P. Jacobs,et al.  Inviscid evolution of stretched vortex arrays , 1986, Journal of Fluid Mechanics.

[12]  On the numerical simulation of the unsteady wake behind an airfoil , 1987 .

[13]  Matthew Thomas Scott.  Nonlinear airfoil-wake interaction in large amplitude unsteady flow , 1987 .

[14]  J. Mccune.  Unsteady wing theory - The Karman/Sears legacy , 1988 .

[15]  Unsteady 3-D Aerodynamics of Slender Wings in Severe Maneuver , 1988 .

[16]  Hewett A. O Benson.  Apparent-mass and on-board circulation of Joukowski airfoils and cascades in severe unsteady motion , 1989 .