综合管廊舱燃气泄漏集聚模型实验与数值模拟研究

Study on model experiment and numerical simulation of gas leakage accumulation in the utility tunnel cabin

为研究综合管廊内燃气泄漏时燃气在防火门附近和管廊夹层的集聚,用氖气代替燃气在模型实验台进行实验研究,并用数值模拟验证氖气代替燃气的可行性,提出在管廊防火墙最高处增设防火风口和在管廊夹层敷设诱导风机的建议,并模拟该方法下燃气集聚的改善效果。结果表明:泄漏口位于防火门上游侧时,靠近防火门上游和下游上部均出现燃气集聚现象;泄漏口直径的增大加剧燃气的集聚;燃气管道压力越大,燃气泄漏浓度和扩散波动程度越高;在管廊夹层死角处也会形成燃气集聚;防火门上方加设防火风口和管廊夹层内敷设诱导风机能有效改善防火门附近和夹层的燃气集聚情况。

In order to study the accumulation of gas near the fire door and the mezzanine of tunnel when gas leaks in the utility tunnel,an experimental study was carried out on the model test bench with neon gas instead of gas.Numerical simulations were also used to verify the feasibility of neon gas instead of gas.It is proposed to add fire-proof air outlets at the highest point of the utility tunnel firewall and to install inducing fans on the mezzanine of tunnel.And the improvement effect of gas accumulation under this method was simulated.The results show that when the leak is located on the upstream side of the fire door,gas accumulation occurs in the upper part of the upstream and downstream near the fire door.The increase in the diameter of the leak aggravates the accumulation of gas.The higher the gas pipeline pressure is,the higher the gas leakage concentration and diffusion fluctuation is.Gas accumulation also forms at the dead corners of the utility tunnel mezzanine.The addition of fire-proof air outlets above the fire door and inducing fans in the mezzanine of the utility tunnel can effectively reduce the gas accumulation near the fire door and in the interlayer.