Comparison of theoretical method of the gas flow in corridors with experimental measurement in real scale

Abstract

The paper describes the principles of ventilation of underground structures, tunnels and corridors. It also presents a theoretical method of assessment of corridor structures where primary monitored values are velocity of spreading, temperature and depth of forehead of smoke wave in dependance on time and distance from the centre of fire. Results predicated by a theoretical method are compared to the values measured in a real large-scale experiment conducted in the tunnel Valik on the D5 motorway in the Czech Republic. This paper evaluates a possible use of theoretical calculation for constructions of tunnels. The presented method is based on a buoyancy of flue gases. At common constructions is the buoyancy effect one of the most significant phenomena, which affects the smoke movement. The specific type of tunnel constructions is the cause of phenomena that fundamentally affect the smoke flow. The importance of a buoyancy effect decreases significantly while the openness for tunnel construstions and the effect of fire ventilation becomes the major influences. These described effects are the cause of significant variances in realized experiments and applied theoretical method. Based on mentioned important discrepancies it is impossible to recommend this presented calculation method for using of tunnel constructions. The method would require an important modification so that would take into account the specifics of tunnel constructions.