university of florida thesis or dissertation formatting template

Doublet-lattice
Denegri 1, 7,12,13 analyzes the F-16 using double-lattice method aerodynamics and classical
flutter analysis. He shows a correlation to LCO-sensitive configurations but is not able to give
response amplitude characteristics.
ZAERO
Toth 30 and Chen 31,32 approach the LCO prediction from a structural perspective and
assume that nonlinear structural damping is the significant factor. They present two F-16 aircraft
configurations that differ only in the missile launchers carried underwing and on the wingtip. A
more refined aerodynamic model of the aircraft and stores is used in ZAERO that leads to an
improvement in the solution results. Their results show a humped damping curve with stability
transitions that correlate to the onset and subsequent cessation of the LCO measured during flight
testing. They also find that ZONA’s modal-based Transonic Aerodynamic Influence Coefficient
(ZTAIC) matrix can correlate classical flutter, typical LCO, and non-typical LCO based on V-g
(flutter speed vs. damping) plots. By examining the shape of the unstable mode in the V-g
diagram, flutter engineers should be able to describe the type of LCO the aircraft will exhibit in
flight. These results are encouraging for the cases examined. However, their work addresses a
category of LCO behavior where the oscillation onset occurs at a relatively low subsonic Mach
number. In this case, the linear aerodynamic assumption is quite valid but may not prove quite as
useful for the purely transonic cases (such as those presented in this dissertation).
Harmonic Balance
Thomas 33-41 performs F-16 LCO calculations using a harmonic balance (HB) approach.
HB provides a computationally efficient method for modeling the nonlinear unsteady
aerodynamic forces created by finite amplitude motions of the wing. From this frequency domain
31