Flutter analysis of multi-directional functionally graded sector poroelastic disks

Abstract

For the first time, in this article, stable/unstable zones of multi-directional functionally graded (MD-FG) sector disks under aerodynamic pressures are sought. Also, because of porous media, the system is modeled as a poroelastic system. The damping matrix, together with the aerodynamic stiffness matrix, is modeled upon Krumhaar's modified supersonic piston hypothesis. For more accuracy of the results, the Series-Fourier expansion of displacement fields in two-dimension is considered. To solve the partial differential equations, the singular convolution integration method with a singular convolution, as a numerical solver, is used. The precision of the outcomes is verified with those available in the other published research. It is demonstrated that the 3D model has great accuracy in predicting the flutter phenomenon and supersonic vibrations of the MD-FG sector disks. Finally, it has been shown that MD-FG power indices, radius ratio, boundary condition, poroelastic media, geometry, Mach number, aerodynamic pressure, and air yaw angle, in addition to Biot's coefficient, have a crucial role in the stable/unstable zones of the MD-FG sector disks under various conditions. One of the most important results of the current report is that the alteration in material properties of the MD-FG sector disk does not alter the yaw angle in which maximum frequency occurs.