natural gas emission incidents simulation and calculation of vent in distribution networks (case study: fars gas company)

The objective of this paper is the numerical simulation of accident consequences of natural gas release. failure of the pipeline can lead to various outcomes, some of which can pose a significant threat of irretrievable damage to people and properties in the immediate vicinity of the failure location. to make the solution and results more similar to actual scenario, gas leakage rate from pipeline fracture is investigated in the steady state flow (hole and pipeline models) and transient flow modes are examined. the numerical results show that if the pressure at the fracture point is equal to the atmospheric pressure, the mach number is smaller than one. in the pipe model, if the length of the pipe is long and the pressure difference between the inside and outside of the pipe is high, then the mach number tends to one and the gas leak rate to the sound speed. the fugitive emission from all instruments was measured using hiflow sampler and the emission from accidents was calculated using phast software.