Abstract
Many engineering applications can benefit from reducing the weight of structures. While approaches for optimizing the topology of both continuous solids and discrete frame structures have been available for some time, the introduction of additive manufacturing procedures has made it possible to create more complex geometries. On the other hand, one of the greatest challenges in using hydrogen fuels lies in the development of hydrogen storage systems. Among hydrogen storage technologies, the storage of hydrogen in solid-state compounds like Metal Hydrides (MH) appears to be the most feasible solution, as it is safer and has a higher hydrogen volumetric density. However, one downside of MH is its gravimetric density, which prevents its effective use in mobility applications. A novel approach to solving this problem is to integrate the reactor tank into the frame and chassis of the vehicle itself. In this study, a topology-optimized MH container based on a gyroid structure is proposed. The topology optimization method is adopted for the vehicle part geometry that is already filled with the gyroid structure. The proposed geometry is then analyzed with Finite Element Analysis (FEA) and Computational Fluid Dynamics (CFD) to assess its mechanical and heat transfer characteristics, as well as the hydrogen charging rate capability of MH inside the structure. The use of topology optimization with the SIMP method resulted in a 17 % increase in overall chamber volume and almost 50 % reduction of HE material, which affected the overall volumetric and gravimetric density of the reactor. Although the strength of the optimized structure showed a measurable decline, it was able to withstand the given mechanical shear load. The displacement of the structure showed more than usable rigidity of less than 0.2 mm displacement, making it suitable for use in assembly parts like vehicle frames or chassis. The optimized structure also showed a slight increase in charging rate, making it a promising approach for designing the container.
