Nonlinear vibration analysis of delaminated composite plate structures in supersonic flow
Bence Hauck, András Szekrényes
Abstract
Abstract This paper concerns the nonlinear vibration analysis of thin laminated plate-like composite airfoils subjected to supersonic flow with the presence of delamination by modelling thin airfoils as plate structures. This study provides an adequate finite element family for modelling the fluid-solid interaction which is developed by employing the first-order shear deformable plate theory with the concept of two equivalent single layers. The aerodynamic pressure is described by adopting the so-called piston theory. Since the mechanical response of these structures is moderately nonlinear, the von Karman nonlinear strains are used to model the nonlinear behaviour. The developed finite element model is verified by applying it to intact structures and comparing the results to a well-known semi-analytical solution. Considering the size, location and depth of the delamination as stability parameters, different stability maps are generated by carrying out the linear stability analysis of the investigated structures. In accordance with the stability maps, the nonlinear vibrations are examined in particular cases including stable and unstable scenarios. To reduce the time consumption and CPU requirement of the computations, an improved Newmark direct time-integration scheme is developed with an iterative predictor-corrector procedure.