ABSTRACT
This paper concerns a practical case of transversal ventilation system applied to a unidirectional road tunnel and how the functional design has enabled the optimization of the tunnel geometry, reducing the estimated implementation costs and thereby promoting the award of the Contract with the subsequent realization of the works. The ventilation system described is related to the twin-tube tunnel (2.4 km long) located on the new roadway S2-Southern Bypass in Warsaw – Task A. It is then described the starting assumption about the performance of the ventilation system, the draft presented by the Contracting Authority during the tender phase and the optimization proposals, these last ones as results of the analysis of the required performances. Furthermore, It has been demonstrated the applicability and effectiveness of the Computational Fluid Dynamics (CFD) and the Fire Safety Engineering for the validation of the transversal ventilation system in a road tunnel with unidirectional traffic.
