Optimal core design of MR based smart panels subject of flutter instability

Abstract

This study deals with aeroelastic and flutter analyses of the partially treated MR sandwich plates in the supersonic airflow. It also identifies the optimal locations of the MR segments in the core layer, which results in maximum flutter boundaries of the MR sandwich plate, in response to the airflow. Classical and Mindlin plate theories, Hamilton’s principle and first order linear piston theory are employed to derive the governing equations of motion of the structure. The assumed mode technique is used to solve the equations and specify the instability bounds of the sandwich plate. An experiment on the dynamic characteristics of the partially treated sandwich plate incorporating MR fluid as the core layer is conducted to demonstrate validity of the developed model. Then, the effect of number and locations of the MR pockets on the flutter suppression of the sandwich plates is comprehensively investigated. Also, an optimization problem is formulated to identify the optimal locations of the MR treatments, which maximize flutter boundaries of the structure in different levels of the magnetic flux density.