Avanced modeling for the control of tunnel ventilation during excavation and operation

Innovative tools are necessar y to obtain the optimal operating conditions of the ventilation systems in a reasonable lapse of time and accurately. This can be achieved both with appropriate numerical approaches to the full domain as the model order reduction techniques and with the domain decompositions methods as the multi-scale physical decomposition technique. The reduced order mode techniques such as the Proper Orthogonal Decomposition - POD are based on the snapshots method, which provides an optimal linear basis for the reconstruction of multidimensional data. The physical decomposition achieved through mul-ti-level approaches uses the accuracy of the Computational Fluid Dynamics - CFD code in the near field, e.g. the region close to the fire source, and takes advantage of the low computational cost of the 1-D model in the region where gradients in the transversal direction are negligible. In this paper, the features of these two approaches when applied to the control of tunnel ventilation systems are presented. In particular, the use during construction the phase and during operation are discussed.