Numerical Simulation of Pollutant Channeling between Adjacent Road Tunnels

Abstract

With the development of highway tunnels, the increasing number of continuous tunnels has brought forth a growing concern regarding the dispersion of pollutants between tunnel entrances. This study employs numerical simulations with Star CCM+ to analyze factors influencing pollutant dispersion between continuous tunnel entrances, such as inlet and outlet velocities, longitudinal spacing, and lateral wind. Results indicate that maintaining a constant longitudinal size ratio while increasing velocity ratio augments intrusion ratio. Altering longitudinal spacing and equivalent diameter does not affect dispersion with constant velocity and size ratios. The intrusion ratio decreases with increasing longitudinal size ratio at a constant velocity ratio. Increased lateral wind weakens intrusion with constant velocities and longitudinal size ratio. This investigation aims to identify ventilation measures for mitigating pollutant dispersion impact in continuous tunnels.