相向射流与竖井作用下的隧道烟气分层稳定性研究

Study on stratified stability of smoke in tunnel under the action of opposite jet and shaft

开展相似试验,研究相向射流与竖井协同作用下,公路隧道火灾烟气分层稳定性与火源功率、相向射流风速及测点位置之间的关联关系。试验设计了3组共50个工况,分析了不同工况下不同位置处的火灾烟气分层稳定性。试验结果表明:上下游风速差值越小,火灾烟气分层越稳定,上下游风速差值越大,火灾烟气层越紊乱。相向射流风速相同,火源功率对火灾烟气分层稳定性并无明显影响。由于热浮力、射流及竖井抽吸作用力之间的相互作用,不同位置处火灾烟气分层稳定性呈现出差异性。

Through the similar test,the relationship between the smoke stratification stability of highway tunnel fire and the power of fire source,the wind speed of opposite jet and the position of measuring point under the synergistic action of opposite jet and shaft was studied.Three kinds of 50 working conditions were designed,and the stratification stability of fire smoke at different locations under different working conditions was analyzed.The test results showed that the smaller the upstream and downstream wind speed difference is,the more stable the fire smoke stratification is,and the larger the upstream and downstream wind speed difference is,the more disordered the fire smoke layer is.When the wind speed of the opposite jet is the same,the power of the fire source has no obvious effect on the stratification stability of the fire smoke.Due to the interaction among thermal buoyancy,jet and shaft suction force,the stratification stability of fire smoke at different locations is different.