Abstract: To study the influence of the roof structure of the gasoline and hydrogen filling stations on the hydrogen leakage and diffusion, the variation characteristics of hydrogen movement velocity and volume fraction under four different roof structure conditions of original canopy, flat roof, quadrangular platform type and quadrangular pyramid type were modeled, calculated and analyzed. The results show that different roof shapes have different effects on the hydrogen movement velocity. The flat roof is more conducive to maintaining the horizontal movement trend of hydrogen, the inclined roof is more conducive to maintaining the upward movement trend of hydrogen, while the quadrangular pyramidal roof is more conducive to the upward diffusion of hydrogen. The diffusion of hydrogen clouds is restricted by the ordinary canopy, and hydrogen is easy to accumulate between the roof and side panels, which results in a large area of high volume fraction hydrogen. The pyramidal roof is a safer roof design, which can better hinder the accumulation of hydrogen in the station. The results can provide a reference for the roof design of gasoline and hydrogen filling stations.

Key words: canopy structure, hydrogen diffusion, movement velocity of hydrogen diffusion, hydrogen volume fraction, gasoline and hydrogen filling station