Open AccessInfluences of stack effect and longitudinal ventilation on the movement of buoyancy-driven contaminants in sloping tunnels
Author(s) -
P. Li,
Tao Du,
Dong Yang
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/609/3/032073
Subject(s) - buoyancy , stack effect , stack (abstract data type) , environmental science , flow (mathematics) , mechanics , geology , ventilation (architecture) , geotechnical engineering , meteorology , physics , computer science , programming language
Sloping tunnels widely exist in mountainous regions and urban underground traffic systems. The dynamics of buoyancy-driven contaminants in a naturally ventilated slopping tunnel are generally different from that in a horizontal tunnel. Using the brine-water method and the light attenuation technique, we demonstrate that buoyancy-driven source location and source reduced gravity have significant influence on the steady-state density distribution in the sloping tunnel. The results suggest that the stack effect is an important factor influencing the movement of the buoyancy-driven flow in sloping tunnels. Subsequently, the dynamics of the buoyancy-driven flow in a longitudinally ventilated sloping tunnel are investigated. It is found that, under the combined effects of longitudinal ventilation and stack effect, multiple steady states exist for identical boundary conditions.