Experimental study on effect of blockage on smoke temperature in tunnel fire

doi:10.16265/j.cnki.issn1003-3033.2022.10.1792

Abstract

Abstract:

In order to study the influence of blockage effect on the smoke temperature distribution characteristics in a tunnel fire， a series of 1∶20 small-scale model experiments were carried out in this paper. By varying fire power parameters， tunnel slope， blockage location and blockage length， the smoke spread time， maximum ceiling temperature rise and dimensionless longitudinal temperature distribution in the tunnel fire have been analyzed in depth. The results show that： the blockage length has little effect on the smoke temperature characteristics， while the blockage location has a greater impact. The spread speed of smoke to the side with blockage is greater than that in the scenario without blockage， and greater than that in the scenario with blockage on another side of the fire source. When the fire power changes， the location effect of blockage will also change. Due to the blockage effect， the smoke temperature attenuation rate decreases during the longitudinal spread of smoke to the side with the blockage， while the longitudinal spread to the side without blockage is not disturbed by this effect.

Key words: tunnel fire, blockage, tunnel slope, smoke temperature, fire power

YANG Yuxuan, CHENG Huihang, LONG Zeng, CHEN Junfeng, LIU Chang, ZHONG Maohua. Experimental study on effect of blockage on smoke temperature in tunnel fire[J]. China Safety Science Journal, 2022, 32(10): 135-141.

Figures/Tables 12

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火源尺寸/ cm×cm	平均质量损失速率/ （g·s^-1）	试验火灾功率/kW	原型隧道火灾功率/ MW
5×5	0.038	0.73	1.3
8×8	0.127	2.46	4.4
10×10	0.247	4.81	8.6

隧道坡度/%	下坡侧		上坡侧
隧道坡度/%	b	R²	b	R²
0	0.79	0.957	0.76	0.954
1.74	1.00	0.914	0.53	0.948
3.49	1.04	0.989	0.38	0.922
5.24	1.20	0.981	0.34	0.924
6.99	1.50	0.980	0.28	0.921
8.74	1.72	0.985	0.17	0.930