Effects of Stiffeners on Vibrations of Fiber-Reinforced and Laminated Composite Shells

Abstract

Vibration characteristics of fiber-reinforced and laminated composite paraboloidal shells with stiffeners are studied by Finite Element Method. The effects of stiffeners on natural frequencies are investigated by using a developed code in ANSYS. The developed code is verified by using several case studies on special cases of the present problem due to the lack of the present case in the reachable literature. Case studies are related with determination of natural frequencies of composite square plate, composite cylindrical shell, stiffened isotropic square plate, and isotropic paraboloidal shell of revolution. Aftervalidation of the developed computer code, effects on number of stiffener and cross-section of the stiffener on natural frequencies of fiber-reiforced and laminated composite paraboloidal shells are presented.