A novel design solution for improving the performance of composite toroidal hydrogen storage tanks

This paper presents a novel design approach combining isotensoidal structures with non-geodesic winding patterns, which is able to significantly improve the geometric flexibility and structural performance of composite toroidal hydrogen storage tanks. The fiber trajectories are allowed to deviate from geodesics and the slippage coefficient is introduced to enlarge the design opportunities of toroidal pressure vessels. With the aid of the netting theory and fiber slippage law, the governing equations for specifying the meridian profiles of non-geodesic-isotensoids are derived based on the condition of uniform fiber stress. The desired toroids are then obtained by forcing the non-geodesic isotensoidal meridian profiles to become closed. The resulting cross-sectional shapes and winding angle distributions are outlined, corresponding to various slippage coefficients of non-geodesics. The vessel performance factors are determined to demonstrate the better structural efficiency that the application of non-geodesics can achieve. The results show that the vessel performance improves by using non-geodesics, due to the overall decrease in winding angles of the fiber trajectories. It is also concluded that the structural performance of isotensoidal toroids can be further improved with increasing the slippage coefficient of the non-geodesic trajectories. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.