A Review of the Piston Effect in Subway Stations

Abstract

In recent years the piston effect in subways has become a topic of interest for researchers and engineers. Many publications have appeared on this topic, but reliable information is scattered and poorly organized. This review paper covers the latest publications on the piston effect in subways. We compile information about the mechanism of the piston effect, evaluate its influence, and describe how it can be effectively utilized.

Environmental and Health Effects of Ventilation in Subway Stations: A Literature Review

“…High ventilation rates and frequent facility utilizations require ventilation systems to keep their cleanliness and efficiency to ensure abundant clean air entering subways. Furthermore, some recent energy-saving studies propose to utilize piston winds through train movement [241][242][243][244] and buoyancy-driven airflows through hot pressing [245], which make wind environments and pollutant transmissions more complicated. Spaces and airflows in subways are so complex that they cannot merely introduce fresh air to dilute and then exhaust air outside.…”

“…Hence, piston winds seriously disorder operations of ventilation systems [80,256,257]. In 2013, Pan et al systematically reviewed the piston effect in subway stations from the aspects of formation mechanisms, simulation analyses, environmental effects, and control measures [242]. Based on the review of Pan et al, the latest health-related studies are reviewed.…”

“…Ventilation not only significantly affects the thermal and humid environment in a subway station but also plays a vital role in air pollutant transmission and air pollutant-related infection. On the one hand, integrated and intelligent ventilation systems can improve IAQ and conserve energy in subway stations [80,233,[241][242][243][244]. In a subway station, piston winds, hot pressures, the stack effect, and the subway climate can all increase the ambient airflow, regardless of whether the mechanical ventilation system is in operation.…”

A review of traditional and advanced technologies for the removal of particulate matter in subway systems

“…34 Thus, optimal use of the piston effect can provide significant energy savings. 51 Moreno et al 34 confirmed that the PM 10 level of narrow platforms with single-track tunnels were doubled when the ventilation system was turned off.…”

“…The natural ventilation is the use of train-induced wind to naturally vent air in the tunnel without the use of other mechanical forces. 51 It has been reported that the efficiency of this effect is lower than that of the forced ventilation using a fan. The train passing through the tunnel has a double effectpushing the air in front and suctioning the air from the rear with a negative vortex pressure.…”