纵向通风下公路隧道双火源火灾烟气扩散研究

摘 要：采用试验与数值模拟研究隧道双火源火灾临界风速变化，重点研究双火源功率和火源间距对临界风速的影响。结果表明：随着火源间距增加，临界风速逐渐降低，当两火源间距达到极限距离时，临界风速不再变化；当进风口侧火源功率确定时，在极限间距内出风口侧火源功率增大时，临界风速增大，说明出风口侧的火源对进风口侧的烟气回流有促进作用；在极限间距内，临界风速随火源间距增加呈二次方递减到一个稳定值；两火源总功率越大，临界风速随着间距增加降低的幅度越明显。并得到了临界风速的预测公式。

Study on smoke dispersion pattern of dual-fire source fire in highway tunnel under longitudinal ventilation

Experimental and numerical simulations were used to study the variation of critical wind velocity of a dual-fire source fire in a tunnel. The effect of fire power and fire source spacing on the critical wind speed was studied. The results show that: as the spacing between the two fire sources increases, the required critical wind speed of smoke gradually decreases, and when the spacing between the two fire sources reaches the limiting distance, the required critical wind speed of smoke no longer changes; when the power of the fire source on the inlet side is determined, the required critical wind speed increases when the power of the fire source on the outlet side increases within the limiting distance, which means that the fire source on the outlet side has a facilitating effect on the smoke back-flow on the inlet side; within the limiting distance, the critical wind speed decreases quadratically to a stable value with the increase of spacing; the larger the total power of the two fire sources, the more obvious the reduction of the critical wind speed with the increase of the spacing. And the prediction formula of the critical wind speed was obtained.