Abstract
The accidental release of LPG from trucks or other containers is a dangerous event due to the subsequent dispersion followed by possible fires and explosions. Unfortunately this scenario is that of the accident occurred at the Viareggio railway station on the night of June, 29 2009, where the released LPG caused a large number of fatalities.Some simulations of the event, as proposed in published papers, assume a liquid release for the calculation of the discharge time.
Since the LPG is at saturated conditions, it is subject to a flash during discharge as soon as the pressure is lowered; so the real event is more complexas the LPG discharge moves from mixed phase to vapor phase.This article presents rigorous simulations of the event focusing on the discharge time period required to empty the damaged vessel.The simulation uses ‘state of the art’ equations of state to model the thermodynamic behaviour of the fluid during the release. Vapor generation due to depressurization and related temperature effects are fully modelled.