[Paper Review] Perforation Effect on a Rectangular Metal Hydride Tank for the Hydriding and Dehydriding Process by Using COMSOL Multiphysics Software

Evangelos I. Gkanas, Sofoklis S. Makridis+2 more|arXiv (Cornell University)|Mar 19, 2013

Hydrogen Storage and Materials14 references3 citations

TL;DR

This study presents a 3D transient numerical model of a perforated rectangular metal hydride tank using COMSOL Multiphysics to simulate hydriding and dehydriding processes in LaNi5 powder. The model couples energy, mass, and momentum conservation equations, showing strong agreement with experimental data, demonstrating that perforation enhances heat and mass transfer, thereby improving reaction kinetics and thermal management in metal hydride reactors.

ABSTRACT

In this paper, a 3 Dimensional dynamic model of a perforated rectangular metal hydride tank is presented. The metal hydride tank consists of powder LaNi5 and the tubes are organized in the geometry of the rectangular in order to simulate the flux of the ambient air through the reactor, which affect hardly both the hydriding and the dehydriding reaction. A simulating study is made by solving simultaneously the energy, mass and momentum differential equations of conservation by using Comsol Multiphysics (version 4.2) software. The simulation results show great agreement with the experimental data.

Motivation & Objective

• To investigate the influence of perforation geometry on heat and mass transfer in a rectangular metal hydride tank.
• To simulate the dynamic hydriding and dehydriding processes in LaNi5-based reactors under realistic flow conditions.
• To evaluate the thermal and kinetic performance of the system using a coupled multiphysics model.
• To validate the simulation results against experimental data for accuracy and reliability.

Proposed method

• A 3D transient model was developed using COMSOL Multiphysics v4.2 to simulate the hydriding and dehydriding processes in a rectangular tank filled with LaNi5 powder.
• The model solves coupled conservation equations for energy, mass, and momentum to represent heat transfer, hydrogen diffusion, and fluid flow through the perforated structure.
• Perforations were modeled as porous media to simulate ambient air flow and enhance convective heat transfer.
• The geometry was designed to mimic real reactor configurations, with tubes arranged in a rectangular pattern to facilitate air flow and thermal regulation.
• Boundary conditions were applied based on experimental operating parameters, including temperature, pressure, and flow rate.
• The simulation results were validated by comparing predicted temperature and hydrogen concentration profiles with experimental measurements.

Experimental results

Research questions

• RQ1 How does the presence of perforations affect the thermal response and hydrogen absorption/desorption kinetics in a rectangular metal hydride tank?
• RQ2 To what extent do fluid flow and convective heat transfer through perforations improve the efficiency of the hydriding and dehydriding processes?
• RQ3 How well does the 3D multiphysics model predict experimental behavior in terms of temperature evolution and hydrogen storage capacity?
• RQ4 What is the impact of geometric arrangement and porosity of the perforated structure on system performance?

Key findings

• The 3D simulation model showed strong agreement with experimental data, validating the accuracy of the numerical approach.
• Perforation significantly enhanced convective heat transfer, reducing thermal gradients within the tank during hydriding and dehydriding cycles.
• Improved heat removal and distribution led to faster reaction kinetics and more uniform hydrogen absorption and desorption rates.
• The model successfully captured the transient behavior of temperature and hydrogen concentration profiles over time.
• The coupling of energy, mass, and momentum conservation equations enabled realistic prediction of system dynamics under varying operating conditions.
• The results demonstrate that perforated rectangular geometries are effective in improving thermal management and overall performance of metal hydride reactors.