Enclosure safety in a case of hydrogen, CNG, or LNG accidental release from a bus tank

Abstract

Hydrogen, CNG and LNG are highly explosive gases, which can create extremely hazardous conditions if released into an enclosure. The gases’ behaviour was checked under accidental release conditions by CFD simulations. It has been proved that too large a gas release diameter orifice could create a dangerous situation, and a gas concentration level above the lower explosive limit, even before emergency ventilation activation. The suggested practical solution for the hazard mitigation could be a limitation of the gas installation diameters fitted on the buses.