T.A.L.P.A.: an innovative facility for cotinous longitudibnal air flow profile acquisition in tunnels

The knowledge of the flow field inside road tunnels under fire conditions and normal operation is only approximate andpartial. The reason is that while the full three-dimensional, unsteady problem is out of reach of numerical methods, on theother hand accurate measurement of the airflow in road and railway tunnels constitutes an extremely challenging task.Aiming at performing easy and accurate in situ measurements of the flow field in road tunnel under different conditions, aninnovative experimental facility for the continuous acquisition of the longitudinal velocity profile has been designed and built.The facility is made up with a survey rake with five bidirectional vane anemometers, which is mounted on a small electricvehicle that can travel through the tunnel at constant speed. This paper reports the design procedure of the measurementfacility, with particular focus on the conception and realization of the vehicle carrying the survey rake. Results of the firstexperimental campaign carried out under the 11611 meters long Mont Blanc road tunnel are also presented to corroborate thevalidity of the approach adopted and the accuracy of the measurement chain.