Optimal design of a metal hydride hydrogen storage bed using a helical coil heat exchanger along with a central return tube during the absorption process

Eisapour, Amir Hossein; Naghizadeh, Ali; Eisapour, Mehdi; Talebizadehsardari, Pouyan

Abstract

Metal-hydride (MH) reactors are one of the most promising approaches for hydrogen storage because of their low operating pressure, high storage volumetric density and high security. However, the heat transfer performance of the MH reactor for high hydrogenation rate is inferior. In this study, the heat transfer and hydrogen absorption process of metal hydride tank performance in Mg2Ni bed is analyzed numerically using commercial ANSYS-FLUENT software. The MH reactor is considered a cylindrical bed including a helical tube along with a central straight return tube for the cooling fluid. The effects of geometrical parameters including the tube diameter, the pitch size and the coil diameter as well as operational parameters on the heat exchanged and hydrogen absorption reactive time are evaluated comprehensively. The results showed that the helical heat exchanger along with central return tube could effectively improve heat exchanged between the cooling fluid and the metal alloy and reduce the temperature of the bed results in a higher rate of hydrogen absorption. For a proper configuration and geometry of the helical coil heat exchanger with a central return tube, the absorption reaction time is reduced by 24% to reach 90% of the storage capacity. After the optimization study of the geometrical parameters, a system with the heat exchanger tube diameter of 5 mm, coil diameter of 18 mm and the coil pitch value of 10 mm is recommended to have lower hydrogen absorption time and higher hydrogen storage capacity. The presented MH reactor can be applied for improvement of heat exchange and absorption process in industrial MH reactors.

Citation

Eisapour, A. H., Naghizadeh, A., Eisapour, M., & Talebizadehsardari, P. (2021). Optimal design of a metal hydride hydrogen storage bed using a helical coil heat exchanger along with a central return tube during the absorption process. International Journal of Hydrogen Energy, 46(27), 14478-14493. https://doi.org/10.1016/j.ijhydene.2021.01.170

• Journal Article Type: Article
• Acceptance Date: Jan 24, 2021
• Online Publication Date: Feb 23, 2021
• Publication Date: Apr 19, 2021
• Deposit Date: Apr 28, 2025
• Journal: International Journal of Hydrogen Energy
• Print ISSN: 0360-3199
• Electronic ISSN: 1879-3487
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 46
• Issue: 27
• Pages: 14478-14493
• DOI: https://doi.org/10.1016/j.ijhydene.2021.01.170
• Keywords: Magnesium based metal hydride reactor, Hydrogen absorption, Helical coil heat exchanger, Reaction time, Heat transfer
• Public URL: https://nottingham-repository.worktribe.com/output/22727061
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0360319921003207?via%3Dihub
• Additional Information: This article is maintained by: Elsevier; Article Title: Optimal design of a metal hydride hydrogen storage bed using a helical coil heat exchanger along with a central return tube during the absorption process; Journal Title: International Journal of Hydrogen Energy; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.ijhydene.2021.01.170; Content Type: article; Copyright: © 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.