CFD simulation of flashing jet applied to area classification

Abstract

AbstractIndustrially flammable gases are stored and transported in the form of pressurized liquid. The occurrence of leaks from pressurized flammable liquids in vessels or pipes may cause a two‐phase release, containing a mixture of liquid droplets and vapour of flammable substances. This phenomenon, called flashing, occurs when a superheated liquid comes into a lower pressure environment. The study and understanding of this type of release are of fundamental importance for the hazardous area classification that is addressed by the IEC 60079‐10‐1 standard, which recommends the use of computational fluid dynamics (CFD) for the calculation of a hazardous area. This work uses CFD to predict the hazardous area extent and volume that resulted from the complex two‐phase release, which had not been addressed previously in other literature. The influence of wind and release conditions on the area classification is analyzed. The CFD results agree with the available experimental data. A new parameter as a function of the volume and extent of the jet is proposed for hazardous area classification.