Influence of urban highway tunnel upper vents groups number on natural ventilation efficiency

Abstract

For natural ventilation, setting upper vents of urban highway tunnel is one possible method for improving the environment and the outlet of the tunnel. In this present paper, one 1,000 m tunnel is chosen as the analysis object, according to the universal size of road tunnel. The relationship between the number of upper vents groups and pollutant dispersion in the tunnel was analyzed with aid of the subway environment simulation (SES) simulation software. The results show that the urban highway tunnel with upper vents can emit pollutant along the tunnel. Meanwhile, for the same quantity, total area of the vents and a certain vents spans, two vent groups are the best type of ventilation, from which about 50 % pollutant emission can be emitted. In addition, the single group is the worst type of ventilation, from which only 37 % pollutant emission can be emitted. © Springer-Verlag Berlin Heidelberg 2014.