Volume 18: Sustainable Energy Solutions for a Post-COVID Recovery towards a Better Future: Part I

Investigate on hydrogen dispersion of complex air supply and exhaust system in large underground garage Fan Mo, Bin Liu, Huiru Wang, Xiaohui She, Lin Teng, Xi Kang, Peng Han*

Abstract

With the improvement of energy consumption level in China, environmental pollution and energy shortage are becoming more and more prominent. Hydrogen energy as a clean and efficient new energy has gradually entered the public’s field of vision, H2 was developed rapidly. Hydrogen fuel cell vehicles (HFCVs) is an important development direction of H2 energy application as a net zero carbon emission transportation form. However, the development of H2 energy has been hindered by H2 storage, transportation and other problems in practical applications. H2 is lighter than air and will dissipate rapidly while existing leakage in open environment. But H2 will accumulate and cause incalculable damage while existing accidental leakage in semi-enclosed or enclosed space (i.e., garage or tunnel). The study to leakage of high pressure H2 is the necessary prerequisite for the promotion of hydrogen fuel cell vehicles. In this paper, the effects of atmospheric stability conditions and source term variations on confined space dispersion scenarios were systematically evaluated by using the coupled integral model and computational fluid dynamics (CFD) method.An integral model was used to simulate the process of source term formation after 3.5kg high pressure hydrogen was released. This paper also studied the influence of the existence of obstacles and the arrangement of vents on H2 concentration distribution in the leakage process emphatically. Combined with the simulation results at the initial stage of leakage, a feasible method was provided for the risk assessment of hydrogen fuel cell vehicle garages.

Keywords Hydrogen dispersion，Integral models，Computational Fluid Dynamics modeling，Air supply and exhaust system