Study on the Flow-dynamic Characterization of the Lateral Mechanical Extraction System in Tunnel Fire

摘要

A reasonable mechanical extraction rate is the key to ensure a better exhausting efficiency in case of a tunnel fire. According to the application of the lateral smoke exhaust system in the tunnel, the FDS numerical simulation is used to study the flow-dynamic characterization. An orthogonal test is conducted to analyze the influence of the smoke vent area, location of smoke vent and the exhaust rate on smoke exhausting efficiency. The interface temperature calculated by the N-percent method, the temperature distribution and the smoke flow near the smoke vent are analyzed. According to this research, the exhaust rate and location of smoke vent have a great influence on the smoke exhaust efficiency than the smoke vent area. The lateral smoke vent should be mounted in the top of the side wall and the exhaust velocity of a single smoke vent should not greater than 6m/s.