Abstract
The fact that many underground facilities, as large-scale spaces, differ in their geometric characteristics, continually sets new tasks for the researcher investigating the fluid phenomena. In this manner, we performed a computationally aided investigation of the new covered traffic road-communication that goes under a part of the Slovenian capital of Ljubljana. Although not yet finished – we were in position with the employed RANS transient approach (interpreting turbulence by k-ε model) using the technical drawings of the road-tunnel for the design of the computational domain, to give a CFD-forecast of the effectiveness of ventilation in the event of both, 40 and 80 MW fires.