Dynamic Study of Hydrogen Absorption in Metal Hydride-based Storage Systems

Abstract

The paper is described an analysis of using Metal Hydride (MH) in hydrogen storage systems during charging process . A 3-D partial differential equations algebraic model is employed to describing the kinetic reaction of hydrogen charging into different MH beds (LaNi_4.75A_l0.25, and LaNi₅). A software simulation is discussed and created for MH reactor configurations equipped with and without heat pipe. The COMSOL 5.2a Multi-physics software was used for this simulation by solving simultaneously the energy, mass-momentum, and kinetic differential equations of conservation. The reaction kinetic of hydrogen is analyzed depending on some parameters including: (reactor design, hydrogen inlet pressure, cooling temperature and convective heat transfer coefficient). The results showed a good compatibility between the software simulations and the experimental work for LaNi₅ previously published by the authors. This is sensibly where the value of error was less than 8%, this confirm the efficiency of model to captured the key experimental trends. The maximum charging capacity is recorded in case of LaNi₅, while the fastest charging duration time is recorded for LaNi_4.75Al_0.25.  Each MH  materials has different hydriding process depending on it’s thermo-physical properties. The hydrogen charging into MH systems inside the visuals is exothermic reaction associated with a  high inner temperature achieved, and high heat energy release.