Abstract:

Theoretical analysis and numerical simulation are used to study the impact of the relative position of the fire source and the smoke extraction shaft on the point smoke extraction effect under a city underground road fire condition. The research results show that under a certain amount of smoke exhaust, the closer the exhaust fan to the fire source is, the better the exhaust effect is in the one-way smoke exhaust mode. When the location of the fire source is biased to one of the shafts, if the amount of smoke exhaust is enough, only the shaft fan close to the fire can be turned on to exhaust smoke. When the fire source is in the middle of the two shafts, the two-way smoke exhaust mode can be used. When the fire is located below the shaft, the shaft above the fire can be used to exhaust smoke. When adopting this working condition, the fire resistance rating of the flue plate in the tunnel should be considered comprehensively. 

Key words: smoke exhaust shaft, smoke exhaust mode, smoke exhaust effect, fire resistance rating