Study On The Optimization Of Highway Tunnel Ventilation System On Detailed Structure And Longitudinal Fans Arrangement

Based on the ventilation assumption of highway tunnel,the paper utilizes numericalsimulation,theoretical analysis and other methods to research some problems in Tunnelventilation,such as the length of short duct,the factors which affects the air flow pattern inshort duct,the type of vents,the best angle of vents,the fan at the outlet, the longitudinalconcentrated arrangement of the fan.The main conclusions gained are as the following:(1) The system of super long tunnel longitudinal ventilation with air sending andexhausting is the result of the harmonization of the various parts, the longth of the shortduct do no busniess of the air flow pattern in the duct. When the civil structures of thetunnel is given, the fundamental factors that affect it is arrangement of the fan power inevery parts;(2) The area of the exhausting duct should be closed to the product of cross-sectionalarea of tunnel and the discharge coefficient of the vents;(3) It would be advantage that to set the exhausting duct non-symmetrical than to set itsymmetrical;(4) The best angle of intersection of the exhausting duct orifice with tunne is the anglethat makes the funds of the subtraction of the saved expenses by ventilation improved andthe increased costs of the construction investment;(5) To some super long tunnel,arranging the fan at the outlet to the normal position asother fans would be better;(6) To the tunnel that using Jet ventilation, In some cases, there are advantages whenmakes the fans concentrated in longitudinal arrangement under the premise of meeting therequirements of longitudinal spacing of fans.