Smoke Control of Fires in Subway Stations

We investigate the effectiveness of the smoke control scheme of the Gong-Guan subway station (GGSS), a typical subway station of the Taipei Rapid Transit System and whose mechanical control systems are also standard in modern subway station design. Three-dimensional smoke flow fields under various kinds of fires are computed by computational fluid dynamics techniques and the results are illustrated on various cross-sectional planes. Results indicate that the stack effect plays a deterministic role in smoke control when a fire occurs near the stairwell; under such circumstances, no mechanical smoke control is necessary. When a fire occurs in other places, such as at the end or the center of the platform, the current mechanical control schemes of GGSS are effective; namely, the smoke can be well controlled, either it is confined to a small region or is evacuated from the station, leaving the four exits free of smoke so that the passengers can escape through them. The effect of the platform edge door (PED) on smoke control is also investigated. With the PED, the effectiveness of the present smoke control system for fires occurring on the chassis of a train, a serious fire in the subway station, increases. We also propose an innovative smoke control scheme with a PED, which turns out to be much more efficient in evacuating smoke than that currently used. This study provides both valuable information for the design of passenger evacuation routes in fires as well as criteria for the design of a smoke control system for subway stations. [PUBLICATION ABSTRACT]