城市地下快速路入口段火灾烟气蔓延规律

依托上海北横通道泸定路枢纽工程,建立依托工程的全尺寸仿真模型,选取城市地下快速路入口段的主线风速和匝道风速作为变量,研究火灾发生后隧道内人员安全高度处的温度、能见度、CO浓度等变化规律。结果表明,主线风速与匝道风速的提高都会导致温度下降速率减缓,能见度上升,CO浓度降低,但是匝道风速对烟气的影响要弱于主线风速的影响。主线与匝道共同提供排烟风速时,保持临界风速即可有效排烟,主线为1.72 m/s,匝道为1.84 m/s。

Study on the law of fire smoke spread in the entrance section of urban underground expressway

In this paper, relying on the Shanghai North Transverse Corridor Luding Road Hub Project, a full-size simulation model relying on the project was established, and the mainline wind speed and ramp wind speed at the entrance section of the urban underground expressway were selected as variables to study the change rules of temperature, visibility, CO concentration and other rules at the safe height of the people in the tunnel after the fire. The results show that the increase of both the mainline wind speed and the ramp wind speed leads to the slowing down of the temperature decrease rate, the increase of the visibility, and the decrease of the CO concentration, but the effect of the ramp wind speed on the smoke is weaker than the effect of the mainline wind speed. When the mainline and ramp together provide the smoke exhaust air speed, the smoke can be effectively exhausted by maintaining the critical air speed, which is 1.72 (m·s-1) for the mainline and 1.84 (m·s-1) for the ramp.