C304 トンネル坑口における排気ガス持ち出し量の数値予測

抄録

The purpose of this investigation is to predict contaminant emission from a automotive tunnel portal by using 2-D flow simulation. In order to simulate flow around moving vehicles in the road tunnel, sliding mesh technique is utilized. The sliding mesh for moving vehicles moves relatively for the fixed mesh for the tunnel and outer region. The amount of the contaminant emission depends on the carrying out quantity by the moving vehicles only without the ventilation effect of the tunnel facilities. In the case of a forward flow ventilation (4m/s), moving vehicles carry out 6.4% of the contaminant gas. On the other hand, in the case of a backward flow ventilation (4m/s), carrying out quantity decreases from 6.4 % to 2% and overall emission is almost zero. It reveals that the massive exhaustion at the exit portal is useful for reducing the contaminant emission.