Dynamic Instability Behaviour Prediction of Curved Shell Composite Structure Using Different Higher-Order Theories

This research paper explores the dynamic instability behaviour of laminated curved shell composite structures under in-plane loading conditions.

Two higher-order theories (nine and ten degrees of freedom at each node) are adopted to develop the composite mathematical model considering the in-plane loading conditions to compute the parametric instability based on the finite element (FE) discretization technique. The system’s differential equations of motion are converted into a set of ordinary differential equations and addressed as an ordinary eigenvalue solution utilizing the Bolotin approach.

The precision and adaptability of the current model are confirmed by comparing the current outcomes with the existing solutions. The influence of numerous constraints of the laminated curved shell composite structure is investigated, such as different structural forms, thickness and aspect ratio, diversity in end condition, and static and dynamic load factors. Additionally, the compared outcomes (excitation frequency) between two different models (Model I and Model II) are varying from 0.93 to 34% under the static load factors (low to high range).

The outcomes of the developed numerical models are carefully examined, compared and discussed. Model II responses are showing a higher side excitation frequency when compared to Model I due to the presence of stretching term in displacement kinematics. The excitation frequency increases due to a decrease in static load factor and an increase in curvature and aspect ratio.