户外多火源燃烧危险性试验研究

摘 要：开展了不同火源间距（1.5D、1.75D、2D）和不同油盘直径（1.0，1.4，1.7 m）下户外多火源燃烧和单火源燃烧对比试验，试验中利用摄像机、电子天平、热电偶阵列分别监测了火焰高度、火源燃烧速率和几何中心温度。结果发现，四火源燃烧时各个火源的燃烧速率高于相同直径下单火源的燃烧速率，而且均在火源间距1.5D时发生了火焰融合现象，火焰融合高度高于相同直径下单火源的火焰高度，表明多火源燃烧危险性更大。四火源融合后，在连续火焰区、间歇火焰区、羽流区几何中轴线火焰温度随高度的指数变化分别为0.13、-1.02、-1.46，与普通浮力池火公认的中轴线温度变化基本保持一致，表明多火焰融合后形成了一个普通的浮力池火。

Experimental study on combustion risk analysis of outdoor multiple fires

Abstract: The ultra-long submarine tunnel has a special structure, so smoke exhaust and air supply are the key factors restricting the development of the ultra-long submarine tunnel. Based on Yanda Undersea tunnel, a new scheme of smoke exhaust and air supply without shaft in the sea is designed. It adopts centrifugal air compressor to pressurize fire smoke into seawater at high speed, and provides additional air supply through compressed air. FDS was used to simulate 56 groups of working conditions with different smoke exhaust volume and air supplement volume. By analyzing smoke layer thickness, smoke spread length, smoke exhaust efficiency and evacuation environment, the optimal smoke exhaust air supplement scheme was found. The results show that when the exhaust volume is 140-180 m3/s, and the air supplement volume is 190-210 m3/s, respectively, accounting for 50% and 70% of the exhaust volume, the system has the best exhaust effect. Among them, the smoke exhaust system of 180 m3/s, 50% air supplement volume and 200 m3/s, 70% air supplement volume has the best smoke exhaust effect, and the latter is better than the former. In practical engineering application, it can be considered that the design smoke exhaust volume is 200 m3/s and air supply volume is 140 m3/s.