不同火灾规模下隧道水幕线性喷水强度的研究

为了探究火源功率和水幕线性喷水强度对烟气特征参数和水幕阻烟隔热能力的影响，以全尺寸隧道为研究对象，采用FDS数值模拟方法，还原验证了前人使用的小尺寸模型，研究了20组工况下烟气特征参数变化的规律。研究结果表明:根据相似性原理还原后的全尺寸模型在相同工况下的模拟结果与小尺寸实验基本一致；水幕系统降低遮光率的效果随线性喷水强度增加而增强，当线性喷水强度增至一定程度时，遮光率和隔热效率无明显变化；对于中、大型规模火灾，水幕有效作用时间出现减少的情况；火源功率为5，20，30 MW的小、中、大规模的隧道火灾，综合考虑经济性和水幕效果，建议分别选择水幕的线性喷水强度为8，14，16 L/(s瘙
簚m)。

Study on linear spray intensity of water curtain in tunnel under different fire scales

In order to explore the influence of fire source power and linear spray intensity of water curtain on the characteristic parameters of smoke and the smoke blockage and heat insulation abilities of water curtain, taking the full scale tunnel as the research object, the small scale model which had been used by the predecessors was restored and verified by using the FDS numerical simulation method, and the change laws of the characteristic parameters of smoke under twenty groups of conditions were studied. The results showed that the simulation results of the full scale model restored according to the similarity principle were basically consistent with those of the small scale experiments under the same conditions. The effect of water curtain system on reducing the shading rate increased with the increase of linear spray intensity, and when the linear spray intensity increased to a certain extent, the shading rate and heat insulation efficiency had no obvious change, but for the medium scale and large scale fire, the effective acting time of water curtain decreased. For the small scale, medium scale and large scale tunnel fire with the fire source power of 5, 20 and 30 MW respectively, it was recommended that the linear spray intensity of water curtain should be chosen as 8, 14 and 16 L/(s·m) respectively when comprehensively considering the economy and the effect of water curtain.