Experimental and analytical investigation of vibration characteristics in T700 carbon fiber composite cylindrical shells

In this study, the free vibration characteristics of carbon fiber reinforced composite cylindrical shells are investigated through both experimental and finite element methods. Modal tests were conducted on a carbon fiber reinforced composite shell, and a corresponding finite element model was developed to calculate its modal characteristics. The calculate results were com-pared with the experimental results to verify the accuracy of the finite element model characteristics. The validated finite element model was used to conduct comprehensive parametric studies of both thin shells (h/R≤0.05) and thick shell (h/R≥0.1) shells, and the systematic comparative analysis was carried out. The effects of the number of layers, ply angle, stacking sequence, boundary conditions, length-radius ratio, and thickness-radius ratio on the vibration characteristics were systematically analyzed. Research findings indicate that: (1) The natural frequency of the shell demonstrates greater sensitivity to ply angles than to stacking sequences. (2) The [θ/−θ]₂ stacking sequence demonstrates more pronounced sensitivity to ply angle variations compared to the [90/θ/−θ/90] stacking sequence. (3) Thick shells demonstrate more pronounced sensitivity to ply angle variations compared to thin shells. (4) Both ply angle variations and thickness-radius ratio changes significantly influence the fundamental frequency. This work provides novel and experimentally verified insights into the dynamics of thick composite material shells and lays the foundation for their structural design.