The Study Of Fire Smoke Motion Mechanism About Urban Underground Link Tunnel Under Different Curvature And Ventilation Condition

Urban underground link tunnel as the new underground connecting tunnel and belong to limited narrow space. It mainly includes the main tunnel, connecting tunnel and tunnel’s import and export, etc. The structure, ventilation facilities and fire danger more complex than general tunnel. At present, there is no perfect system of urban underground traffic tunnel professional fire prevention design specifications, some research also mainly concentrated in the subway, railway tunnel, and mountain highway tunnel, other forms tunnel fire such as curve tunnel, fire related research especially rare. The different curvature ventilation conditions underground contact the tunnel of fire smoke flow movement mechanism research is rarely reported. The study of fire smoke motion mechanism about urban underground link tunnel under different curvature and ventilation condition is necessary.The research mainly take underground traffic tunnel as the research object,combined with field investigation, theoretical analysis and CFD numerical simulation and research the urban underground traffic tunnel under the conditions of different curvature and ventilation:(1) Through the field investigation analysis the fire research status of underground traffic tunnel and summarizes the structural characteristics, fire causes, fire characteristics and hazard.(2) Using the FDS and Pyrosim software construct the fire smoke flow movement model of urban underground traffic under different curvature and ventilation conditions.Determine the working condition parameters through analysis the tunnel fire prevention design specification, finally summarizes the fire simulation conditions.(3) According calculate the 16 kinds of fire condition of urban underground traffic ring model, and study the urban underground traffic tunnel’s influence of fire dynamics parameters such as the smoke flow and the temperature, visibility, smoke layer height under the different curvature and the longitudinal ventilation velocity.(4) Contrast the simulation results and summarizes fire smoke motion mechanism about urban underground link tunnel under different curvature and ventilation conditions, final put forward series of smoke control measures and suggestions.The research results can offer reference of fire ventilation mode selection and design,fire prevention and evacuation plan to the urban underground traffic tunnel. In addition,it has important value to research underground restricted space and other related curve tunnel.