纵向通风条件下对隧道内烟气运动影响因素的实验研究

通过在中国科学技术大学火灾科学国家重点实验室进行的小尺寸隧道火灾实验,研究了不同坡度、火源功率以及纵向烟控风速对隧道内烟气运动的影响。结果表明:隧道坡度、火源功率与纵向烟控风速的大小对烟气层沉降都有着重要的影响。坡度越大烟气所受到的浮升力越大,冷空气的卷吸能力越强,因此烟气降温越快,烟气沉降速度也越快。纵向烟控风速越大,烟气层冷却越快,从而越易沉降。火源功率越小,供给烟气层的对流热量越少,烟气层温度越低,浮力越小,则烟气层越易沉降。

Experimental study on the effect of longitudinal ventilation and factors on smoke movement in tunnels

In this paper the influence of the smoke layer height change under the different conditions of fire power, slope and speed of vertical ventilation control was studied by taking the tunnel laboratory bench in the key laboratory of the university of science and technology of China as the object. The results showed that： the greater the slopewas, the greater float lift was, ability to absorb was stronger, so the faster the flue gas temperature droped, and the more rapidly the subsiding speed was. The speed of longitudinal ventilation was the greater, the flue gas was cooler. The smaller the fire power was, the convection heat supply gas layer was less, the lower the temperature of flue gas, the smaller the buoyancy, the flue gas layer was easy to settlement.