Numerical Study on the Optimization of Hydrogen Storage Performance in a Finned Sinusoidal Corrugated Tube Reactor

Metal hydride (MH) systems offer a compelling route to solid-state hydrogen storage, yet their practical charging rate is fundamentally limited by the low effective thermal conductivity of the hydride bed and the substantial exothermic heat generated during absorption. Addressing this thermal bottleneck without sacrificing hydride volume remains a central challenge in MH reactor design. This study proposes an integrated thermal enhancement strategy in which transverse fins are coupled with a sinusoidal corrugated heat transfer tube, combining the boundary-layer disruption effect of corrugated geometry with the extended heat transfer surface provided by fins. A three-dimensional transient numerical model is developed within a porous-medium framework to compare straight-tube and corrugated-tube reactors equipped with different fin arrangements. The influences of corrugated-tube inlet radius, fin length, and fin inclination angle on hydrogen absorption performance are then systematically evaluated. The results show that positioning transverse fins on the upper side of the wave crests establishes the most direct conductive pathway between the hydride bed and the coolant, while appropriate fin geometry effectively suppresses low-conversion dead zones and improves the spatial uniformity of the reaction field. Compared with the finless sinusoidal corrugated-tube reactor and the conventional transverse-finned straight-tube reactor, the optimized configuration shortens hydrogen storage time by 62.74% and 42.05%, respectively, confirming that the synergistic combination of transverse fins and corrugated-tube geometry constitutes an effective and compact thermal management solution for MH hydrogen storage reactors.