Simplified expression for estimating release rate of hazardous gas from a hole on high-pressure pipelines

Correlations for estimating natural gas leakage from above-ground and buried urban distribution pipelines

“…Also for buried gas pipe, hole is a subscriber boundary between pipe and the soil and this boundary should be disconnected between pipe and soil; after disconnecting, two boundaries are created and type of these boundaries is according to table 3. The pipe under investigation is located in the urban distribution gas pipelines with low pressure level and relatively small pipe diameter and this means that natural gas can be treated as an ideal gas [21][22][23]38]. Therefor there is a different between current study and other models that investigated leakage for high-pressure gas pipelines [18,39], in which it should be take into account dispersion of the pressure along the pipe.…”

Comparison study on qualitative and quantitative risk assessment methods for urban natural gas pipeline network

“…If the gas leakage catches fire after it forms a persistent vapour cloud but not intensively mixing with air, a fire ball ensues. The thermal radiation flux of fire ball combustion can be conservatively estimated according to the corresponding fire ball combustion model [34]. If the gas leakage catches fire after it intensively mixes with air and forms a persistent vapour cloud, it will lead to a significant flash fire or unconfined vapour cloud explosion.…”

An integrated quantitative risk analysis method for natural gas pipeline network

“…The process of leakage is a isentropic adiabatic expansion process, which can be described by: (a) hole models (Montiel, Vılchez, & Casal, 1998); (b) pipe models ; (c) approximate fitting algorithm Jo & Ahn, 2003;Luo, Zheng, Zhao, Huo, & Yang, 2006); (d) dynamic differential equation model (API PR581, 2000;Yang, Li, & Lai, 2007;Mazzoldi, Hill, & Colls, 2008;CCPS, 1994). Recently the hole models have been widely used in literatures as a general computational method to fit the need of quantitative risk analysis, and it is used to calculate the gas release rate in this paper.…”

“…By assuming that the energy releases uniformly within the duration of the fire ball, the thermal radiation flux of fire ball can be conservatively estimated, according to the corresponding calculation model (Luo et al, 2006).…”