Stability of Filament-Wound Composite Cylinders Subjected to Hydrostatic Pressure

Abstract

In order to know the mechanical properties of filament-wound composite cylindrical shells subjected to hydrostatic pressure, solve the buckling problem of pressure hull in deep sea and provide reference for engineering design, it is necessary to research the stability of filament-wound composite cylindrical shells. Based on the theory of thin shells, the governing equations were derived. Stability of composite cylindrical shells was researched by employing Galerkin method to solve the eigenvalue equation. The critical buckling pressure was calculated for cross filament-wound, metal-filament-wound and angle filament-wound composite cylinders under hydrostatic pressure. Compared to the test results, the numerical solution was illustrated to be feasibility. On this basis, the numerical method was interacted with genetic algorithm to search optimum stacking sequence and filament winding angle. Three types of winding pattern [(±θ)12], [(±θ1)x/(±θ2)12-x] and [(±θ1)4/(±θ2)4/(±θ3)4] were investigated, . Further, the effects of winding angle and the corresponding layer number on the critical buckling pressure were evaluated. It was shown that winding angle variation affected the critical buckling pressure significantly. Stability was greatly improved by numerical optimization, and the maximum critical buckling loads are increased by 31.31%, 43.25% and 57.51% compared with the base line, respectively. As the number of design variable increased, the carrying capacity was improved markedly. The optimal critical buckling pressure was increased by 57.17%.