Numerical investigation on the dispersion of hydrogen vapor cloud with atmospheric inversion layer

Characterization of the dispersion behaviors of spilled liquid hydrogen is necessary from the safety prospective. In this study, the two-phase flow of liquid hydrogen spill is predicted with the mixture multiphase model, Lee model and Realizable k-epsilon model, and the dispersion of hydrogen vapor cloud with the atmospheric inversion layer is numerically analyzed. The inversion layer restrains the upward movement of the cloud and the mixing of the cloud with air, increasing its ground-level hydrogen concentration. The heights of the flammable cloud can be reduced by 5.71%, 10.49% and 12.86%, respectively, with the temperature lapse rates of 0.03, 0.06 and 0.10 K/m in our investigated scenarios. Besides, the 'restraining effect is strengthened by increasing the ground air temperature if the temperature lapse rate remains unchanged. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.