Thermal stability characteristics and limit cycle oscillation of smart skin structures

Smart skin structures are analyzed for thermal stability behaviors and limit cycle oscillations in supersonic range of airflows. The skin is made up of multi-layered sandwich panel using carbon/epoxy, glass/epoxy, and dielectric polymer layers. And the model is based on the first-order shear deformation plate theory, and von Karman strain-displacement relationships are used to consider the moderate geometrical nonlinearity of the structure. In order to study the effects of the airflow, first-order piston theory is adopted to represent the pressures. Also, Newmark time integration method is applied to obtain the numerical results in this work. To check the validity of present outcomes, results are compared with previous data. Specifically, the stability boundaries are obtained for various ranges of temperatures and aerodynamic pressures. Then, the regions for buckling, post-buckling, dynamic instability, and limit cycle oscillation of the structures are clearly discussed. For more analysis, the smart skin is investigated for the different sizes and shapes of dielectric portion within enclosure layer in detail.