The retarding mechanism research on smoke movement of top structures in long-narrow space.

In order to study the flow law of smoke generated by fire after passing through several top structures such as smoke barriers, FSD numerical simulation method was used to compare the smoke spreading situation of the long-narrow space model in the case of no smoke barrier, single smoke barrier and multi smoke barrier. The velocity field distribution of smoke migration and the flow rate change in different sections were studied. The results showed that the time for smoke to reach the end of the long-narrow space were 15.9 s, 17.1 s, 18.8 s and 25.5 s, respectively, in the case of no smoke barrier and 1, 2 and 4 smoke barriers. The reason why smoke barriers retarded the smoke spreading was that the top structures such as smoke barriers could reduce the relative flow velocity of smoke layer and lower air layer, which reduced the entrainment of air and the amount of flue gas generated; the retarding effect of multi smoke barrier was better than that of single barrier, and the smoke spreading speed was slower. [ABSTRACT FROM AUTHOR]