Numerical study on structural optimization of a sinusoidal corrugated tube metal hydride hydrogen storage reactor

Metal hydride hydrogen storage technology has garnered significant attention due to its high volumetric density and safety. However, the low effective thermal conductivity of the bed layer leads to severe heat accumulation, which significantly hampers the reaction rate. The core challenge in reactor design lies in enhancing heat transfer while maximizing the retention of hydrogen storage capacity. This study proposes a hydrogen storage reactor with a sinusoidal corrugated tube structure, aiming to enhance the hydrogen charging and discharging performance with minimal impact on the total volumetric storage capacity. Based on the porous medium and local thermal equilibrium assumptions, a three-dimensional transient numerical model was established to systematically investigate the coupling effects of corrugation period ( T be ), amplitude ( A ), and inlet radius ( r 2 ) on reactor performance. Analysis reveals that the sinusoidal corrugated tube significantly reduces the temperature gradient in the bed core by increasing the effective heat transfer area and inducing periodic disturbances in the cooling medium. Results demonstrate that compared to the conventional straight-tube structure, the optimized corrugated tube reactor reduces the hydrogen saturation time by 865.5 s, with only a minimal loss in hydrogen storage capacity of approximately 0.307 g. Additionally, The study finds that the hydrogen absorption rate is positively correlated with the corrugation amplitude and inlet radius, but negatively correlated with the period. These optimal structural parameters ( T be = 8 mm, A = 2.5 mm, r 2 = 7 mm) highlight the advantages of sinusoidal corrugated structures in hydrogen storage, providing guidance for the engineering application of metal hydride hydrogen storage reactors. • A novel sinusoidal corrugated tube structure for metal hydride hydrogen storage reactors is proposed. • The influence of key geometric parameters, including period, amplitude, and tube diameter, is systematically investigated. • An optimized reactor configuration is obtained, significantly enhancing heat transfer and reaction efficiency. • The hydrogen absorption time is reduced by 51.89% compared to the conventional straight-tube design.