简 介: |
Composite toroids have emerged as an attractive alternative in many industrial fields where space-saving, weight reduction and non-drift of center of mass are required. This paper aims to determine the optimal winding trajectories for geodesically overwound toroidal pressure vessels, and to demonstrate the favorable performance of the present design method. With the aid of the continuum theory and the geodesic winding law, the equations that determine the required winding trajectories on torus are derived. The general criteria for avoiding fiber bridging on a torus are formulated, based on differential geometry. Next, the initial winding angle and the thickness at the equator are considered as the design variables, while the minimum structural mass acts as the objective function. The optimal geodesic trajectories, corresponding to various relative bending radii, are determined to evaluate the effect on the structural performance of toroids. The stress field is modeled using classical lamination theory and the Tsai-Wu tensor theory is employed as the failure criterion for an individual layer. Results show that the optimization algorithm is efficient and convergent to stable solutions while the optimal winding path obtained does satisfy the requirements for the manufacturing process. Results also indicate that filament-wound toroids designed using the present method show better performance, mainly triggered by maximum utilization of the laminate strength as compared to conventional geodesics-based toroids. The recommended design-oriented method can easily be applied during preliminary dimensioning and optimization of filament-wound toroidal pressure vessels. |