Liying Zhu^*, Ang Wang, Fang Jin

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.6, pp. 1213-1222, 2021, DOI:10.32604/fdmp.2021.017572

Abstract In the present study, the laws of smoke diffusion during forest fires are determined using the general principles of fluid mechanics and dedicated data obtained experimentally using an “ad hoc” imaging technology. Experimental images mimicking smoke in a real scenario are used to extract some “statistics”. These in turn are used to obtain the “divergence” of the flow (this fluid-dynamic parameter describing the amount of air that converges to a certain place from the surroundings or vice versa). The results show that the divergence of the smoke depends on the outside airflow and finally tends to zero as time passes.… More >

Li Lei^*, Wukai Chen, Huiling Li, Shuai Shi

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 837-856, 2020, DOI:10.32604/fdmp.2020.09631

Abstract Urban tunnels are generally narrow and fire smoke can hardly diffuse. In the present study, numerical simulation is used to analyze the diffusion of high temperature smoke produced by fire inside a specific tunnel (the Kaiyuan tunnel). The results are compared with similar data relating to other tests to determine the validity of the numerical method. Moreover, the critical velocity obtained by numerical simulation of 5 MW, 20 MW, and 50 MW fires in curved and linear sections of the considered tunnel is compared with the values obtained using empirical formulas. The results show that, for the tunnel ventilation design,… More >