The study describes and substantiates a new method of assessment of the pressure impact of highly dynamic underexpanded jets from ruptured gas pipelines. The safety norms include recommendations on the registration of such factors; however, they do not contain relevant models. Therefore, the model for the calculation of the dynamic pressure of a gas jet outflowing from a ruptured gas pipeline fills the gap in the industrial safety norms and makes the risk assessment for gas pipelines more comprehensive. The model itself is relatively simple; it does not contain differential equations and can be implemented in the format of electronic tables or a simple screenshot; therefore, it can be used in safety guides and quantitative risk analysis programs.
Due to the absence of full-scale experiments with underexpanded gas jets from high-pressure pipelines (in some cases, up to 20 MPa) (specifically when measuring dynamic properties of the flow such as speed, kinetic energy of turbulence, etc.), the model was validated through the comparison with results obtained via computational fluid dynamics (CFD) software, particularly, using the FLACS solver of Gexcon that complies with global standards of industrial safety. The CFD calculations have been performed axisymmetrically with a “hard wall” boundary condition on the symmetry axis with an open boundary on free surfaces.
Three model tasks for various nominal diameters of a pipeline from 1,000 to 1,400 mm under a similar pressure of 10 MPa have been calculated for the validation. The length of the sonic area has been compared between the model and the CFD, with a variance an error of up to 12 %. The contours of dynamic pressure for the values of 1, 2, and 3 kPa have also been compared. As shown, the difference between the values of dynamic pressure calculated using the model and the values obtained via CFD makes up to 10 %, which indicates the good conformity of the method used.
On approval of the Federal norms and rules for industrial safety, “Safety rules for hazardous production facilities of trunk pipelines: the Order of Rostechnadzor of December 11, 2020 № 517. Available at: https://docs.cntd.ru/document/573174913 (accessed: July 1, 2025). (In Russ.).
2. Об утверждении Руководства по безопасности «Методика оценки риска аварий на опасных производственных объектах магистрального трубопроводного транспорта газа»: приказ Ростехнадзора от 22 дек. 2022 г. № 454. URL: https://docs.cntd.ru/document/1300823854?marker=64S0IJ (дата обращения: 01.07.2025).
On approval of the Safety Guide “Methodology of accident risk assessment at hazardous production facilities of trunk pipeline gas transportation”: the Order of Rostechnadzor of December 22, 2022 № 454. Available at: https://docs.cntd.ru/document/1300823854?marker=64S0IJ (accessed: July 1, 2025). (In Russ.).
3. Абрамович Г.Н. Теория турбулентных струй. Репринтное воспроизведение издания 1960 г. М.: Эколит, 2011. 720 с.
Abramovich G.N. Turbulent jet theory. Reprinted reproduction of the edition of 1960. Мoscow: Ekolit, 2011. 720 p. (In Russ.).
4. Гамера Ю.В., Овчаров С.В., Петрова Ю.Ю. Расчетная модель определения зон поражения от динамического воздействия высокоскоростной струи газа // Газовая промышленность. Спец. вып. «Промышленная безопасность и противопожарная защита объектов газовой промышленности». 2014. № S (712). С. 39–43.
Gamera Ju.V., Ovcharov S.V., Petrova Ju.Ju. Computational model for determining the areas of exposure from the dynamic effect of a high-speed gas jet. Gazovaja promyshlennost. Spec. vyp. “Promyshlennaja bezopasnost i protivopozharnaja zashhita obektov gazovoj promyshlennosti” = Gas Industry. Spec. Iss. Industrial Safety and Fire Fighting Protection of Gas Industry Objects. 2014. № S (712). pp. 39–43. (In Russ.).
5. Гостинцев Ю.А., Едгоров О.О., Файзиев Р.А. Турбулентные струйные течения в стратифицированной атмосфере. Ч. 1. Вынужденно-конвективные струи. Препринт. Черноголовка: ОИХФ АН СССР, 1989. 87 с.
Gostintsev Yu.A., Edgorov O.O., Fayziev R.A. Turbulent jet flows in the stratified atmosphere. Part 1. Forced convection jets. Preprint. Chernogolovka: OIKhF AN SSSR, 1989. 87 p. (In Russ.).
6. Hankinson G., Lowesmith B.J., Genillon P., Hamaide G. Experimental Studies of Releases of High-Pressure Natural Gas from Punctures and Rips in Above-Ground Pipework. 3rd International Pipeline Conference International. 2000. Vol. 1. рр. 53–62. DOI: 10.1115/IPC2000-108
7. Sail J., Blanchetière V., Géniaut B., Osman K., Daubech J., Jamois D., Hébrard J. Review of knowledge and recent works on the influence of initial turbulence in methane explosion. Proceedings of the 10th International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions (X ISHPMIE). Bergen, 2014. pp. 401–432.
8. Hourri A., Angers B., Bénard P., Tchouvelev A., Agranat V. Numerical investigation of the flammable extent of semi-confined hydrogen and methane jets. International Journal of Hydrogen Energy. 2011. Vol. 36. Iss. 3. pp. 2567–2572. DOI: 10.1016/j.ijhydene.2010.04.121
9. Bénard P., Hourri A., Angers B., Tchouvelev A. Adjacent surface effect on the flammable cloud of hydrogen and methane jets: Numerical investigation and engineering correlations. International Journal of Hydrogen Energy. 2016. Vol. 41. Iss. 41. pp. 18654–18662. DOI: 10.1016/j.ijhydene.2016.08.173
10. Об утверждении Руководства по безопасности «Методика оценки последствий аварий на взрывопожароопасных химических производствах»: приказ Ростехнадзора от 28 нояб. 2022 г. № 415. URL: https://docs.cntd.ru/document/1300506231?ysclid=me5o5dggir163293085 ((дата обращения: 01.07.2025).
On approval of the Safety Guide “Methodology of assessment of accident consequences at explosion- and fire-hazardous chemical productions”: the Order of Rostechnadzor of November 28, 2022 № 415. Available at: https://docs.cntd.ru/document/1300506231?ysclid=me5o5dggir163293085 (accessed: July 1, 2025). (In Russ.).
11. Hussein H.J., Capp S.P., George W.K. Velocity measurements in a high-Reynolds-number, momentum-conserving, axisymmetric, turbulent jet. Journal of Fluid Mechanics. 1994. Vol. 258. Iss. 1. pp. 31–75. DOI: 10.1017/S002211209400323X
12. Birch A.D., Brown D.R., Dodson M.G., Swaffield F. The structure and concentration decay of high-pressure jets of natural gas. Combustion Science and Technology. 1984. Vol. 36. Iss. 5–6. рр. 249–261. DOI: 10.1080/00102208408923739
13. Gexcon AS. FLACS v24.1 User’s Manual. Available at: https://www.gexcon.com/support/flacs-cfd/technical-manuals/ (accessed: July 1, 2025).