When a high-speed train enters or exits a tunnel, pressure transients are produced in the tunnel air. With a delay hat is a function of the air tightness of the cars, these transients affect the pressures inside the train.
Principia carried out the passengers’ health and comfort verifications for the Requejo tunnel, associated with the aerodynamic effects of high-speed trains travelling at 350 km/h and conventional, not air-tight, trains at 220 km/h.
The verifications of the pressures triggered were conducted by means of CFD analyses, as well with an in-house program that integrates the governing equations using the method of characteristics.