某公路隧道火灾烟气流动和人员疏散模拟分析

Simulation and Analysis of Smoke Flow and Personnel Evacuation on a Certain Road Tunnel in the Fire

利用Pyro Sim以某公路隧道的设计参数为基础建立FDS+EVAC模型,模拟一定通风速度下的烟气流动和人员疏散情景,并结合公式计算所得的疏散时间对模拟结果进行分析。结果表明:用经修正的量纲一公式计算的临界风速作为模拟通风速度时,烟气产生了一定回流,但不会危及人员安全;当模拟通风速度较小时,烟气产生较严重回流并迅速蔓延至人眼特征高度以下直至地面,危及人员安全;利用量纲一公式及其修正形式计算所得的临界风速与利用Heselden&Kennedy公式及其修正形式的相比,更接近于软件模拟得到的临界风速值。

According to the parameters of a certain tunnel, establish FDS＋EVAC model by using PyroSim software and simulate smoke flow and personnel evacuation at specified ventilation speed. The simulated results were analyzed by combining with evacuation time calculated by formula. Conclusions are summarized as follows： Smoke reversed slightly in simulation when simulated ventilation speed is set as critical velocity calculated by modified normalization formula and the smoke in areas of reversing would not endanger the people there; Smoke reversed seriously in simulation when simulated ventilation speed is set as a smaller value and the smoke in areas of reversing would endanger the people there; The critical velocity of ventilation calculated by Heselden ＆ Kennedy formula is closer to the critical velocity obtained by simulating than the critical velocity calculated by normalization formula.