Using nonlinear energy sink to improve the dynamic behavior of rectangular plate under supersonic aerodynamic flow at different angles

In this paper, the effect of nonlinear energy sink on the dynamic behavior of a rectangular simply supported elastic plate at different azimuth angles is investigated. The plate under study is a thin rectangular plate to which a non-linear energy sink is connected and the supersonic flow of air passes over it. The research aims to improve the behavior of the plate by changing the spatial parameters of the nonlinear energy sink. Classical plate theory is used to obtain plate equations, and von Karman strain-displacement relations are used to consider the nonlinear geometric effect. Modeling of supersonic aerodynamic flow will be based on first-order piston theory. The Kelvin-Voigt model is also used for non-linear energy sinks. The equations were extracted from Lagrange's method and then discretized by Rayleigh-Ritz method and solved by fourth-order Runge-Kutta method. In order to investigate the effects of nonlinear energy sink, the time history curves, phase portraits, Poincaré maps and bifurcation diagrams are used. The results show that using nonlinear energy sinks, the behavior of the plates, which in some cases is very complex, can be changed to a simpler behavior. In some cases, using a non-linear energy sink near the center of the plate is not appropriate.