Experimental study on the distributioncharacteristics of hydrogen leakage in three-dimensional parking garages

This article adopts a reduced size design to construct a medium-sized model (1/15) of a three-dimensional parking garage, and studies the hydrogen release concentration distribution characteristics of hydrogen fuel cell vehicles under different operating conditions. To ensure the safety of the experimental process, helium gas with similar density was used as a substitute for hydrogen gas. The objective was to study the gas concentration distribution in the garage under different leakage flow rates and leakage areas. The impact of leakage flow rate and leakage area on the spatiotemporal distribution of helium concentration in a three-dimensional garage was elucidated. The experimental results indicate that the initial release rate of helium is a significant parameter influencing the stratification of helium concentration in space. If the release flow rate is excessive, the helium concentration will exhibit three distinct phases throughout the entirety of the leakage diffusion process: an initial rapid growth stage, a subsequent rapid decline stage, and finally, a gradual decline stage. The spatial configuration of a three-dimensional garage exerts a discernible influence on the vertical diffusion of helium concentration. The findings of this study can inform the design, construction, and layout of three-dimensional hydrogen sensors in garages, thereby promoting the safe use of hydrogen fuel cell vehicles.