On the modeling of nonlinear supersonic flutter of multibay composite panels

Panel flutter modeling and analysis had regained importance since the mid-'90s. More recently, the idea of considering the mutual influence of adjacent panels in the flutter problem was revisited in studies of panels with multiple supports. These so-called multibay arrangements present flutter mechanism susceptible to jump phenomenon in the Hopf bifurcation diagram. Alternative methods to reduce the computational costs of multibay flutter analysis are desired. The authors propose in this work a comparative study on the supersonic multibay composite panel flutter between the finite element and Rayleigh-Ritz models. The aim is to show how good is the Rayleigh-Ritz approach to match the finite element model results, mainly when the jump phenomenon is present. By adopting the same hypotheses for thin-walled plates, relatively large geometric displacements through the von Karman strain-displacement relations and first-order piston theory the finite element and Rayleigh-Ritz methods were used to attain the respective modeling. A specific symmetric laminate is used, and results from the literature are used to compare the results and to verify the ability of both methods. Furthermore, the computational gain in using the Rayleigh-Ritz compared with the finite element is discussed, thereby ensuring its potential to other analyses, e.g., in optimization schemes.