铁道科学与工程学报2025，Vol.22Issue(2)：817-828,12.DOI:10.19713/j.cnki.43-1423/u.T20240511
考虑边界层分离的隧道侧向集中排烟有效空间及效率研究
Study on effective area and efficiency of lateral concentrated smoke exhaust in tunnel considering the boundary layer separation
摘要
Abstract
The lateral concentrated smoke exhaust mode is preferred in the design of the smoke exhaust system for tunnel fires,and it has wide application prospects.However,the boundary layer separation inevitably takes place when smoke flows from the tunnel to the exhaust vent and the exhaust duct.In turn,this could lead to a reduced effective exhaust space,diminishing smoke exhaust efficiency.To reveal the effective exhaust space and smoke exhaust efficiency affected by the boundary layer separations,1∶10 small-scale model tests and FDS numerical simulations with different heat release rates of fire were carried out in a three-lane immersed tube tunnel.Three boundary layer separation regions in the exhaust vent and exhaust duct were observed and investigated.Moreover,a quantization method for the effective exhaust space considering the volume of boundary layer separation zones was proposed.The effective exhaust space and smoke exhaust efficiency were quantified under the influence of the exhaust volume,the width-height ratio,and the setting height of the exhaust vent.Further,the correlations between effective exhaust space and smoke exhaust efficiency of the exhaust vent and the exhaust duct were analyzed.Specifically,the analysis was done from two perspectives of the exhaust vent and exhaust system.The optimal design parameters of the exhaust vent and exhaust strategy were obtained.The results show that the effective exhaust space and smoke exhaust efficiency in the exhaust vent are more strongly influenced by the exhaust vent parameters and exhaust strategy than the exhaust duct.Particularly,the exhaust vent parameters have a greater effect than the exhaust strategy.The smoke exhaust efficiency is not only related to the effective exhaust space but also closely related to the smoke exhaust rate.Attention should be paid to the effect of boundary layer separation and the smoke exhaust rate on the smoke exhaust efficiency in the exhaust vents.When the heat release rate of fire is 50 MW,the optimal design parameters of lateral concentrated smoke exhaust system are the width-height ratio of 2∶1,the setting height of 5.75 m,and the exhaust volume of 360 m3/s.This work can serve as a guide for fully excavating the potential of lateral concentrated smoke exhaust,and the results can provide a reference for attaining effective smoke exhaust in tunnel fires.关键词
隧道火灾/侧向集中排烟模式/边界层分离/有效排烟空间/排烟效率Key words
tunnel fires/lateral concentrated smoke exhaust/boundary layer separation/effective exhaust space/smoke exhaust efficiency分类
交通运输引用本文复制引用
朱代强,徐湃,蒋树屏,刘奕显,刘灿..考虑边界层分离的隧道侧向集中排烟有效空间及效率研究[J].铁道科学与工程学报,2025,22(2):817-828,12.基金项目
国家自然科学基金资助项目(52008068) （52008068）
重庆市研究生科研创新项目(2023B0004) （2023B0004）
