地铁隧道火灾烟气控制是城市公共安全的一个重要组成部分。在分析地铁隧道火灾烟气流动主要影响因素的基础上，将地铁隧道通风和排烟系统作为一个整体考虑，引入地铁隧道火灾烟气的浮力效应和热阻效应，建立了隧道通风网络火灾模拟的数学模型，分析了地铁隧道火灾烟气逆流的临界条件、临界流速、隧道风流及烟流流速与火灾强度的变化关系，为地铁隧道火灾烟气控制和事故应急处理提供科学依据。

The management of subway tunnel fire smoke is an important component in city public safety. In this paper, on the basis of theoretical analysis of the main factors affecting fire smoke flow in a subway tunnel, the ventilation and exhaust system were considered as a whole and the effects of buoyancy and thermal resistance were introduced. Further, a mathematical model was established to express the relationships between the critical environments, critical velocities, air speeds, smoke speeds and fire intensities. The results can provide instructions for tunnel smoke managements and emergency handling.