New attempts to solve an old problem: aerodynamic measurements in new vehicle tunnels

摘要

Prior to the opening of the new Wijkertunnel near Amsterdam on-site aerodynamic measurements were carried out by NLR under contract to the Dutch Ministry of Transport, Public Works and Water Management. Volume flow rates, created at variousventilation conditions, were measured with a SF{sub}6 tracer gas dilution method as well as with conventional anemometer traverses for comparison. For the determination of the resistance of the empty tunnel tube a velocity decay method was adopted. A newpower efficiency was defined in order to judge the quality of the longitudinal ventilation system. Rather strong and gusty wind conditions occurred during the two days of the measurements. This required special measures in the analysis of the measurements.