1. Lateral flow
The air passage is set on both sides of the driveway, and the fresh atmosphere enters the bridge hole through the side wall of one side and pushes into the driveway, and inhales the exhaust air passage through the bridge hole on the side wall of the other side. It is mostly used for underwater tunnels with the sinking tube method.
2. semi-transverse type
Feed and exhaust ventilation. Lower in cost than horizontal ventilation, but not as effective as horizontal ventilation and control of fire extension for a 1,000 to 3,000 km long tunnel. The air intake channel is normally located above the driveway or under the driveway. The fan exhaust duct of the DECENT tunnel is set under the driveway, and the fresh atmosphere enters the driveway through the entrance. Exhaust-type ventilation. Air duct at both ends of the partition fan, the first half of the exhaust, the second half of the boo. The common air duct used for intake or exhaust air is identified as cat-air ventilation.
3. Longitudinal form
The tunnel fan construction cost is low, the operating cost is low, the shortage is that the pure atmosphere will be accumulated at the tunnel entrance, the depth of harmless energy is higher, and once the fire occurs, the fire will extend vertically along the = spiral, the rescue personnel is not easy to enter the tunnel to save. Oil flow connection – straight short-way tunnel is not suitable for use only one – way long-way tunnel.
4. Horizontal type
According to the flow direction of the inlet and exhaust Xieshan flow across the tunnel, horizontal ventilation can be divided into downflow ventilation. The fan inlet duct in the DECENT tunnel is set above or in front of the driveway, the exhaust duct is set below the driveway, and the cyclone in the driveway moves downward. A transverse cyclone occurring in the driveway is beneficial to eliminate the fire; The flue gas emitted by vehicles is swept away in a short journey, and is evenly concentrated, and there is no easy accumulation of all. The ventilation effect is better, and it is practical for a longer tunnel, but the cost and operating expenses are relatively high.