Description
Retrofit of ventilation systems in ageing infrastructure is increasingly common to improve safety in road tunnels. This paper presents methodology on evaluation and optimization of an existing transverse tunnel ventilation system and model calibration against field measurements of fan curves and system curves to improve safety during an emergency event within the tunnel. The existing system follows a transverse ventilation scheme during normal operation, with multiple emergency ventilation modes to generate longitudinal airflow within the tunnel during a fire event. The emergency ventilation mode is dependent on the location of the fire within the tunnel.
Establishment of existing ventilation system operation conditions by means of physical measurements is presented. Means to calibrate Subway Environment Simulation (SES) and Computational Fluid Dynamics (CFD) models of the existing system is discussed. Subsequent evaluation of ventilation alternatives intended to improve ventilation performance during an emergency fire event was performed using the calibrated SES and CFD models is shown. Results are used to design cost effective retrofits to the existing system resulting in improved safety within the tunnel.
