In order to analyse the feasibility of setting up a ceiling type purification and ventilation system in an urban highway tunnel and study the parameters of ceiling passage, this paper used Fluent software to carry out the 3D numerical simulation. The velocity and pressure distribution in the tunnel and the shunting efficiency were analysed under different angles between the ceiling passage and the main tunnel. Also, by comparing the velocity and CO concentration distribution in the tunnel, the purification efficiency under different conditions is verified. The results showed that the purification efficiency of a purified system is related to angles. With the increasing of angles, the shunting efficiency decreases. The equipment of the ceiling type purification and ventilation system in the urban highway tunnel can effectively reduce the CO concentration. The results show that it is feasible to install a ceiling type purification system as a new tunnel ventilation method, and it can provide a reference for future engineering design.

为了分析在城市公路隧道中建立顶棚式净化通风系统的可行性并研究顶棚通道的参数，本文使用Fluent软件进行了3D数值模拟。分析了顶棚通道与主隧道不同角度下隧道内的速度，压力分布及调车效率。此外，通过比较隧道中的速度和CO浓度分布，可以验证不同条件下的净化效率。结果表明，纯化系统的纯化效率与角度有关。随着角度的增加，分流效率降低。城市公路隧道的顶棚式净化通风系统设备可以有效降低CO浓度。结果表明，安装顶棚式净化系统作为隧道通风的一种新方法是可行的，可为今后的工程设计提供参考。