Suppression of thermal postbuckling and nonlinear panel flutter motions of variable stiffness composite laminates using piezoelectric actuators

Variable stiffness composite laminates (VSCLs) are promising in aerospace engineering due to their designable material properties through changing fiber angles and stacking sequences. Aiming to control the thermal postbuckling and nonlinear panel flutter motions of VSCLs, a full-order numerical model is developed based on the linear quadratic regulator (LQR) algorithm in control theory, the classical laminate plate theory (CLPT) considering von Kármán geometrical nonlinearity, and the first-order Piston theory. The critical buckling temperature and the critical aerodynamic pressure of VSCLs are parametrically investigated. The location and shape of piezoelectric actuators for optimal control of the dynamic responses of VSCLs are determined through comparing the norms of feedback control gain (NFCG). Numerical simulations show that the temperature field has a great effect on aeroelastic tailoring of VSCLs; the curvilinear fiber path of VSCLs can significantly affect the optimal location and shape of piezoelectric actuator for flutter suppression; the unstable panel flutter and the thermal postbuckling deflection can be suppressed effectively through optimal design of piezoelectric patches.