Three Dimensional Numerical Simulation Of Road Tunnel Fire

With the rapid development of road tunnel enterprise,the mileages of tunnel increase.Traffic density and velocity increasing with each passing day,highway tunnel accidents happened frequently.Masses of data indate:Tunnel fire accidents have a great influence on society and economic losses.The analysis of temperature field,concentration field distraction in the fire is very significant for fire proctection design,ventilation equipment operation,evacuation and emergency rescue.This paper statistics large fire accident at home and broad,reviews causes,frequency and characteristics,introduces fire flow control theory and numerical calculation method.Then it carries out numerical simulation of tunnel fire on the early stage through CFD software-FLUENT.In the settings,it adopts VHS combustion model,the buoyancy correction of ?-? turbulent model and DO radiation model.The numerical method is based on finite volume method.SIMPLE algorithm is adopted to the coupling on the pressure and density.According to related studies,it sets reasonable fire heat release curve.Then it carried out unsteady and steady numerical simulation for the fire on the early stage,which mainly considers aspects like the tunnel geometry,ventilation velocity and fire size,which affects the fire field environment.In the fire early,through studying temperature field distribution and unsteady variation laws of vertical section,cross section and horizontal section,It offers advise for lining structure protection,risk assessment,fire proction design,personal evacuation and ventilation control.Besides,through studying Carbon monoxide distributions and variation laws of vertical section and horizontal section,it provides suggestion for personal evacuation and ventilation control.At last,after analyzing and coparing with different escape route,which means summing up the Carbon monoxide concentration field and temperature field in the outcome of simulation,then it finds out the best way to escape.This study enriches the research of fire ventilation,provides reference for the design of tunnel fire proction,evacuation of personnel and operation management.