Impact of Reactor Architecture on Thermal Management and Hydrogen Discharge from LaNi 5 -H 2 Metal Hydride Beds Engineered with Phase Change Material

Abstract

<title>Abstract</title> The performance of solid-state hydrogen storage devices is critically influenced by the design of the heat exchanger. This study explores various reactor designs, incorporating different configurations of phase change material (PCM) within the reactor walls to optimize thermal management. A CFD-based model, implemented in ANSYS Fluent, was utilized to simulate heat and mass transport during hydrogen discharge from a LaNi₅-H₂ metal hydride vessel. The simulations focused on parameters such as temperature distribution, melt fraction, enthalpy, and heat exchange efficiency, including key metrics like heat transfer area and Nusselt number. Among the configurations tested, the design with PCM placed laterally alongside the metal hydride exhibited superior performance, leading to faster heat dissipation and more efficient hydrogen discharge. This optimal design enabled complete hydrogen desorption within approximately 2 hours, compared to 3 to 4 hours for other structures, making it suitable for industrial-scale applications. Moreover, the PCM not only contributed to effective heat transfer but also played a crucial role in regulating the thermal dynamics of the system, ensuring a more controlled and efficient hydrogen release process.