Study On Smoke Spread Characteristics And Smoke Control Design Of Typical Underwater Tunnels

The development of underwater highway tunnels since twenty-first Century is rapid in China,and tunnel fires have occurred frequently.According to the spatial characteristics of underwater highway tunnels,this paper,servicing to engineering designers,combined with the previous research theory,engineering design experience,and the current national standard,uses theoretical analysis and numerical simulation methods to study the fire smoke spread and smoke exhaust design for typical underwater highway tunnels under fire conditions.The main work of this paper is as follows:1、Theoretical analysis and CFD simulation method are used to analyze the temperature along the tunnel roof and the average temperature of cross sections at different distance,the longitudinal spread rate and layer descending velocity of fire smoke.The work is study under the tunnel slope of 0%,1%,2% and 3% and fire release rate of 20 MW,30MW and 50 MW.2、Considering the spatial characteristics of underwater highway tunnel,this paper,taking Guidelines for Design of Ventilation of Highway Tunnels JTG/T D70/2-02-2014 as the design principle,using the theory of fire engineering,studies two kinds of smoke exhausting designment.The parameters such as the volume flux of mechanical smoke exhaust,the area of smoke vent,the section area of exhaust duct,the maximum allowable wind speed,the fire pressure and the pressure resistance of the ventilation in the central exhaust system are designed.The same work is also carried out to obtain the parameters such as critical wind speed,longitudinal smoke volume flux and the pressure resistance of the ventilation in the longitudinal exhaust system.3、MATLAB is used to develop a visual software of the centralized smoke exhaust system and the longitudinal smoke exhaust system of the underwater typical highway tunnel.