Study On Fire Ventilation And Smoke Control Of Single-hole Bidirectional Highway Tunnel

Although in recent years,due to economic development,transport needs,people's convenience needs,there have been a large number of double-hole one-way road tunnel.But in the western region of China,there are still a large number of single-hole two-way road tunnel since terrain,economic and other reasons.Once there is a fire in Single-hole two-way tunnel,because of its opposite characteristics of traffic,it will cause more serious consequences compared with the double-hole one-way tunnel.While in a tunnel fire,flue gas has a great impact on the evacuation.The complexity of the single-hole two-way road tunnel,the complexity of the terrain,the different slope of the tunnel,make the commonly used ventilation control strategy is not very appropriate.This paper mainly studies the ventilation control of single-hole two-way highway tunnel under different slope conditions.And according to the different ventilation direction,the model is divided into two cases,ventilate to the tunnel uphill direction and ventilate to the tunnel downhill direction.The model of single-hole two-way highway tunnel is established by FLUENT software and the fire source power is 20MW.The characteristics of the flue gas field and the temperature field are analyzed.The critical wind speed of the different blowing directions is simulated rely on the actual situation of the project.Based on the above research,the paper will give an appropriate ventilation control strategy.The main research results are as follows:(1)Study on smoke spread and temperature characteristics of fire in different slope and wind speed conditions in the uphill ventilation direction of the tunnel;(2)Study on smoke spread and temperature characteristics of fire in different slope and wind speed conditions in the downhill ventilation direction of the tunnel;(3)Study on the critical wind speed in the uphill and downhill ventilation direction of the tunnel,and to compare with the empirical formula;(4)Based on the above research results,and give the principle of ventilation and smoke control of single-hole bidirectional highway tunnel,finally form the fire ventilation and smoke control organization scheme for single-hole bidirectional highway tunnel under different natural wind speed and wind direction.