As reiterated by Andrews et al., (2010), no evidence exists within the public domain that this kind of a failure mechanism has been witnessed in laboratory experiments or natural gas pipeline systems.
This suggested failure mechanism is further noted by the authors to involve a rather complex interplay of thermo-fluid mechanics of a ruptured pipeline, transfer of heat that is caused by the transfer of cold fluids escaping via a hole or crack, initiation and ultimate propagation of the crack, and finally, crack arrest (Shi Cheng Liu et al., 2006, p.324). .
The work of Andrews et al., (2010) further indicated the need for discussing issues of fluid flow as well heat transfer at the rupture point, fracture initiation , its arrest as full-bore propagation of fracture separately. .
Development of the Previous Model.
The development of previous low-temperature-induced brittle fracture (LTBF) models involved the use of rigorous mathematical models for accurate simulation of the processes that lead to the transition of an originally stable through-wall into a full-blown running fracture. Prior to the work of Mahgerefteh and Atti (2006), a lot of work had a ready been started that employed vigorous mathematical simulation on the basis of method characteristics for accurately stimulating the resulting outflow after rupture of a pipeline (Mahgerefteh et al., 1997, 2000, Zucrow, 1976; Oke et al., 2003). The work of Mahgerefteh and Atti (2006) an important model that inspired the current model employed a robust CFD (Computational Fluid Dynamics) based mathematical model. Mahgerefteh and Atti (2006)'s model accounted for all the essential processes that take place in the pipeline system at the points of depressurization, accounting for real fluid behavior, effects of friction, axial and radial flow taking place within the proximity of the point of puncture as well as the associated thermodynamic oscillations (line pressure and temperature ).