Annotation:
To extinguish large-scale and complex fires that are, for example, forest fires, a significant amount of fire-extinguishing agents and their long-distance feed using high-performance fire equipment, e.g. «Shkval», «Vodoley», and PANRC, are required. For these cases, flexible tanks are recommended for use as intermediate and storage tanks to prepare water solutions for fire-extinguishing agents. Multilayered composite polymer materials are used for their manufacture. When affected by a heat flux, thermal destruction occurs. According to the literary sources, the destruction of polymer materials of foreign manufacture starts at the temperature of 280–290 °С and reaches its maximum at the temperature of 410–420 °С.
In the front of the upper forest fire, total heat fluxes (radiant and convective compounds) up to 120 kW/m2 are implemented, with a radiant heat flux reaching the value of 50 kW/m2. As the distance from the fire front increases, the heat flux decreases exponentially depending on the distance.
An unsteady heat conductivity equation can describe the heating of materials used to manufacture a flexible tank for a multilayered structure in the form of a plate. Three schemes of multilayered structures have been considered; their relevant initial and boundary conditions have been set. A numerical solution for the heat conductivity equation using MathCad 2000 has been proposed. The obtained solution has been verified based on the text example from the US standard ASTMF 1930; the results of the calculation have been compared with the experimental data of laboratory tests in accordance with the GOST R 53264—19 methodology. The calculations comply with the experiment.
Based on the heat flux data for an upper forest fire, the safe distance from the burn front to the flexible tank has been determined by calculations; it exceeds 20 m.
References:
1. Nelyubov V.N. Hydraulic schemes of high-capacity pump-hose systems for extinguishing complex fires. Pozharnaya bezopasnost = Fire Safety. 2024. № 1 (114). рр. 22–29. (In Russ.). DOI: 10.37657/vniipo.pb.2024.114.1.002
2. Nelyubov V.N., Kopylov N.P., Sushkina E.Yu., Novikova V.I. Long distance pumping water supply for firefighting using direct hydraulic calculation and soft reservoirs. Pozharotushenie: problemy, tekhnologii, innovatsii: materialy IX Mezhdunar. nauch.-prakt. konf. (Firefighting: problems, technologies, innovations: proceedings of the 9th International Scientific and Practical Conference). In 2 parts. Pt. 1. Мoscow.: Akademiya GPS MChS Rossii, 2024. pp. 201–204. (In Russ.).
3. Nelyubov V.N., Kopylov N.P., Sushkina E.Yu. Solution and refueling station for preparation of fire-extinguishing agents. Akademiya Gosudarstvennoy protivopozharnoy sluzhby MChS Rossii: Teoriya. Innovatsii. Praktika: materialy nauch.-prakt. konf. s mezhdunar. uchastiem, posvyashchennoy 90-letiyu so dnya obrazovaniya Akademii GPS MChS Rossii (Academy of State Fire Service EMERCOM of Russia: Theory. Innovations. Practices: Proceedings of the Scientific and Practical Conference with International Participation dedicated to the 90th anniversary of the establishment of the Academy of State Fire Service of EMERCOM of Russia). In 5 parts. Pt. 3. Мoscow: Akademiya GPS MChS Rossii, 2023. pp. 214–216. (In Russ.).
4. Konstantinov I.V., Bogacheva E.R., Krasnov E.S. Flexible tanks: application and advantages. Innovatsiya. Nauka. Obrazovanie = Innovation. Science. Education. 2021. № 46. pp. 636–639. (In Russ.).
5. Kurgin R.V. Flexible tanks. Description and application. Ekspozitsiya Neft Gaz = Exposition Oil Gas. 2014. № 6 (38). pp. 80–81. (In Russ.).
6. Samigullin G.Kh., Zakharov A.E. Reduction of fire hazard when using polymeric elastic tanks for oil and petroleum products storage. Problemy upravleniya riskami v tekhnosfere = Problems of Technosphere Risk Management. 2023. № 1 (65). pp. 8–16. (In Russ.).
7. Alekseev S.A. Calculation of flexible aboveground tanks for liquids: a collection of articles on the studies of strength, stability, and resilience of aircraft structures. Trudy Voenno-vozdushnoy akademii im. professora N.E. Zhukovskogo (Papers of the Zhukovsky Air Force Engineering Academy). Iss. 1265. 1980. pp. 208–216. (In Russ.).
8. Shirieva N.S., Shiriev A.K., Tlyasheva R.R., Naumkin E.A. Study of mechanical properties and analysis of low temperatures influence on flexible tank engineering structural material behavior. SPE Russian Petroleum Technology Conference. 2020. DOI: 10.2118/202035-ms
9. Shiryaev E.V., Shabunin S.A., Shvyrkov S.A. Fire hazard assessment of elastic tanks based on thermogravimetric analysis. Pozharovzryvobezopasnost = Fire and Explosion Safety. 2024. Vol. 33. № 3. pp. 36–47. (In Russ.). DOI: 10.22227/0869-7493.2024.33.03.37-46
10. Grishin A.M. Forest fire mathematical modeling and new methods of forest firefighting. Novosibirsk: Nauka, 1992. 408 p. (In Russ.).
11. Butler B.W., Cohen J., Latham D.J., Scuette R.D., Sopko P., Shannon K.S., Jimenez D., Bradshow L.S. Measurements of radiant emissive and temperatures in crown fires. Canadian Journal of Forest Research. 2004. Vol. 34. № 8. рр. 1577–1587. DOI: 10.1139/x04-060
12. Handbook on the selection of means and methods of localization and elimination of fires involving burning liquefied natural gas. Мoscow: VNIIPO, 2023. 67 p. (In Russ.).
13. Kopylov N.P., Sushkina E.Yu., Kuznetsov A.E., Novikova V.I. Experimental assessment of the influence of radiant heat transfer on the transition of a crown fire to settlements. Pozharnaya bezopasnost = Fire Safety. 2021. № 2. pp. 19–25. (In Russ.). DOI: 10.37657/vniipo.pb.2021.76.10.002
14. Agisheva D.K., Shapovalov V.M. Engineering Analysis of Non-Steady-State Heat Conduction of Multi-Layer Plate. Vestnik TGTU = Transactions TSTU. 2002. Vol. 8. № 4. pp. 612–617. (In Russ.).
15. ASTM F1930-18. Standard Test Method for Evaluation of Flame-Resistant Clothing for Protection Against Fire Simulations Using an Instrumented Manikin. Available at: https://www.astm.org/f1930-18.html (accessed: June 20, 2024).
