Sun Z, Lei B
Year:
2001
Bibliographic info:
Hong Kong, City University, Division of Building Science and Technology, 2001, proceedings of IAQVEC 2001, "Indoor Air Quality, Ventilation and Energy Conservation in Buildings: Fourth International Conference", held Changsha, Hunan, China, 2-5 October, 2

A one-dimensional unsteady flow model with a moving pollutant source is used for calculating airflow velocity and pollutant distribution inside the single-track railway tunnel when a train passes through it. Calculations are made about the distribution of pollutant concentration inside the tunnel when a train passes through it under the conditions of different tunnel lengths, different amount of pollutant emissions, etc. Then the length of pollutant segment to be removed is achieved on condition that the Standard of Permissible Concentration of Polluted Air in Railway Tunnel is guaranteed. And the influence of the inertial action of piston wind in the tunnel on tunnel ventilation is analysed. The results show that there are a few problems such as the excess quantity of mechanical ventilation air, the waste of ventilation energy, etc. in the existing tunnel ventilation system. An optimising method of the tunnel ventilation, which can greatly cut down energy consumption, is developed.