Stacking Sequence Design of Flat Composite Panel for Flutter and Thermal Buckling

Abstract

In this paper, we formulate the stacking sequence design of laminated composite flat panels for maximum supersonic flutter speed and maximum thermal buckling capacity. The design is constrained to have stable limit cycle oscillation in the vicinity of the flutter boundary. For the purpose of comparison, we consider both linear and nonlinear panel flutter analyses. Because of manufacturing constraints, the stacking sequence of the laminate is selected from a discrete set of orientation angles. The plate is modeled using von Karman plate equations and assumed to be subjected to uniform temperature differential. The aerodynamic load on the plate is computed using third-order piston theory. The plate equations of motion are derived using Hamilton's principle and discretized using the Rayleigh-Ritz method. The nonlinear panel flutter analysis is performed using an approximate perturbation approach. The Pareto fronts describing the trade-off between thermal buckling and flutter are generated for different panel aspect ratios. It is observed that optimal designs obtained for both linear and nonlinear flutter analyses are similar, with only the predicted flutter speeds different This suggests that, for the purpose of preliminary stacking sequence design, linear flutter analysis is sufficient.