Aeroelastic Analysis of Composite Sandwich Rectangular Plates with Auxetic Honeycomb Core: Free Vibration and Instability Investigation

This paper investigates the free vibration and aeroelastic stability (flutter) behaviors of a cantilever sandwich rectangular plate with an auxetic re-entrant honeycomb core and two laminated composite face sheets under yawed supersonic fluid flow. The first-order shear deformation theory (FSDT) and linear piston theory are utilized to model the plate and aerodynamic pressure, respectively. The set of governing equations and associated boundary conditions are derived utilizing Hamilton's principle and are solved numerically via the differential quadrature method (DQM). The effects of various parameters on the natural frequencies and the critical aerodynamic pressure of the plate are examined, such as the thickness and aspect ratio of the plate, thickness of the auxetic honeycomb core, geometrical parameters of the cells in the auxetic honeycomb core, and the yaw angle. It is observed that the effects of the geometrical parameters of the cells in the auxetic honeycomb core on the natural frequencies are more sensible than the effects of these parameters on the critical aerodynamic pressure of the plate. It is concluded that the critical aerodynamic pressure decreases by increasing the yaw angle from the direction parallel to the clamped edge of the plate to the perpendicular one.