Effect of Heat Transfer Enhancement on Energy Release Rate from a Metal Hydride Tank

Abstract

Metal hydride (MH) attracts considerable attention for not only hydrogen storage devices but also chemical heat pumps (CHPs). Many previous researchers pointed out low effective thermal conductivity of MH packed bed resulted in low performance. Indeed, several attempts have been done to improve it. However, no guideline for improving the thermal performance with heat transfer enhancement has been discussed. In this study, thermal performance for a packed bed reactor of MH is numerically investigated. Diagrams for the heat transfer enhancement are developed according to the numerical results. The previous strategies to improve effective thermal conductivity can be combined with the diagrams for the practical use.

Neutron radiography analysis of a hydride-based hydrogen storage system

“…5b shows an almost linear dependence between the front position and time. Considering an ideal model of uniform heat transfer from a central heater in a cylindrical geometry, the dehydriding front should move at a slower speed as the time increases [19,20]. In this case, heat transfer from the container walls plays an important role in defining this behavior because when this effect starts to show up (from profile p24) dehydriding proceeds not only from the center of the cylinder but also in the transversal direction.…”