Investigation of vibration and stability behaviors of non-homogeneous orthotropic composite cylindrical shells subjected on elastic foundation

The present research studied the free vibration characteristics of non-homogeneous orthotropic thin cylindrical shells resting on elastic foundation. The cylindrical shell can vibrate in different modes and theoretically infinite modes are possible. The axial mode and circumferential mode in any of their combinations define the modes and the corresponding modal frequencies. The study divided into four groups after validation, the first group analysis of cylindrical shells, the second group Analysis for orthotropic cylindrical shells and the third group analysis for cylindrical shells on elastic foundation and finally the fourth group analysis for different cylindrical shells geometry. All the groups tested by using ANSYS software as a tool for finite element investigation. The results observed that when the value of foundation modulus increases, the frequency values increase. Also, when the shell thickness increases, the values of natural frequency increase in addition to the layer's increase which changes the frequency based on the layer's design conditions. Finally, when the length of cylindrical shells increases, the frequency decrease.