Investigation of wall stress development and packing ratio distribution in the metal hydride reactor

Numerical simulation of the parametric influence on the wall strain distribution of vertically placed metal hydride based hydrogen storage container

“…An empirical relationship developed by Haque [11] for grain columns suggests the suitability of exponential relation between porosity and depth. Based on the function fit to experimental data reported by Okumura et al [7]), the porosity of the hydride bed varies exponentially with height from base (z). This can be expressed as follows.…”

“…Experiments by Okumura et al [7] showed that hydride particles get pulverized and fine particles settle gradually towards the bottom, causing very low porosity in these regions. McKillip et al [8] and Nasako et al [9] demonstrated the occurrence of high strains near the container bottom and attributed them to the reduced porosity in those regions.…”

A novel capacitive device for the study of volumetric expansion of hydride powders

“…Samples with higher mass or confined to a limited volume may exert considerable stresses on the walls of the containers [17,18]. On a separated paper, we will present a study on the same hydride, where we show the effects of those situations with our device.…”

“…Nasako et al [16] describe the process of increasing tensions in two steps: The agglomeration of particles, mainly in the bottom of the reservoir, and the pulverization of particles with the cycling process. Okumura et al [17] verified experimentally a non-uniform distribution of particles within a reservoir, with higher packing densities resulting in a larger deformation of the walls at the bottom of the reservoir. The control of the void space above the sample (dead volume) is fundamental to reduce the stress on the walls of a hydride reservoir.…”

Pulverization mechanism of hydrogen storage alloys on microscale packing structure

“…3 [10]. The volumetric expansion rate of the alloy is 24.7% at (mol H)/(mol M) ¼ 1.1 [11]. Alloy particles filtered through a 40e60 mesh are initially packed to a height of 51 mm in the vessel.…”