Experimental determination of the Class B fire extinguishing efficiency using low-expansion foam generated by deflector type sprinklers
Keywords:foam expansion rate, foam stability, foam dispersion, extinguishing efficiency, extinguishing time, extinguishing agent discharge, automatic extinguishing system, sprinkler, field tests
Purpose. To establish the relationship between the foam expansion rate and stability of low-expansion air-mechanical foam generated in deflector type sprinklers for automatic extinguishing systems. To develop a methodology and carry out field tests of foam and foam-water sprinklers. To compare the extinguishing efficiency of the tested sprinklers basing on the results of field tests.
Methods. The method of regression analysis was used to establish the dependence of the foam stability on its expansion rate. The assessment of the extinguishing efficiency of the sprinklers was carried out experimentally, and the processing of the obtained experimental data was carried out using the method of estimation and expression of measurement uncertainty.
Findings. A linear relationship has been established between the expansion rate K and stability C of the low-expansion air-mechanical foam: C = γ·K, where γ is an empirical coefficient depending on the physicochemical properties of the foaming agent. The empirical dependences C = f(K) were obtained for brand of the foaming agents PO-6RZ (6 %). The methodology was developed and field tests of four deflector type sprinklers (V2 sprinkler with optimized geometry on the foam expansion rate, TY 3251 (USA), DPU-15 (Russia) and DVN-11 (Belarus)) were carried out. To compare the extinguishing efficiency of the sprinklers, the extinguishing efficiency indicator Et was used. This indicator takes into account the extinguishing time of the model fire site and the discharge rate of the extinguishing agent. In the result of field tests, it was found that the V2 sprinkler has at least 2.5 times better extinguishing efficiency compared to other tested sprinklers.
Application field of research. The obtained empirical dependence C = γ·K can be used to predict the stability of the foam based on its expansion rate value and vice versa. The developed methods of field testing and evaluating the extinguishing efficiency of foam and foam-water deflector type sprinklers can be implemented for the development of standards, as well as for the study of other sprinklers in conditions close to a real fire.
Kachanov I.V, Karpenchuk I.V., Pavlyukov S.Yu. Ustanovki avtomaticheskogo pozharotusheniya s predvaritel'noy aeratsiey ognetushashchey rabochey sredy [Automatic fire extinguishing systems with preliminary aeration of a fire extinguishing medium]: monograph. Belarusian National Technical University. Minsk: BNTU, 2018. 148 p. (rus)
Kamlyuk A.N., Grachulin A.V. Kompressionnaya pena dlya nuzhd pozharnykh podrazdeleniy [Compression foam for the needs of fire departments]: monograph. Minsk: University of Civil Protection, 2019. 224 p. (rus)
Kamluk A.N., Likhomanov A.O. Increasing foam expansion rate by means of changing the sprinkler geometry. Fire Safety Journal, 2019. Vol. 109. Pp. 102862-1–102862-8. DOI: 10.1016/j.firesaf.2019.102862.
Likhomanov A.O. Comprehensive testing of the sprinkler optimized by the foam expansion rate. Journal of Civil Protection, 2019. Vol. 3, No. 3. Pp. 247–254. (rus) DOI: 10.33408/2519-237X.2019.3-3.247.
Meshman L.M. Effect of irrigation intensity design value dictating the sprinkler on the hydraulic parameters of the distribution network AFES. Fire and Explosion Safety, 2019. Vol. 28, No. 2. Pp. 93–97. (rus)
Likhomanov A.O. Vremya svobodnogo goreniya topliva v model'nom ochage dlya naturnykh ispytaniy pennogo orositelya [The time of free combustion of fuel in the model center for full-scale testing of the foam sprinkler]. Proc. XIV Intern. scientific-practical conf. «Obespechenie bezopasnosti zhiznedeyatel'nosti: problemy i perspektivy», Minsk, April 8–9, 2020. University of Civil Protection. Minsk, 2020. Pp. 84–86. (rus)
Korol'chenko D.A., Sharovarnikov A.F., Degaev E.N. Ognetushashchaya effektivnost' peny nizkoy kratnosti [Fire extinguishing efficiency of foam of low expansion rate]. Nauchnoe obozrenie, 2015. No. 8. Pp. 114–120. (rus)
Khil' E.I., Voevoda S.S., Sharovarnikov A.F., Makarova I.P. Experimental determination of minimum discharge intensity and optimum rate of foaming agent input during suppression of oil products flame. Fire Safety, 2015. No. 4. Pp. 76–81. (rus)
Likhomanov A.O., Govor E.G., Kamlyuk A.N. The substantiation of the application of deflector sprinklers manufactured by additive technologies in experimental studies of qualitative characteristics of the low-expansion air-mechanical foam. Journal of Civil Protection, 2018. Vol. 2, No. 1. Pp. 25–39. (rus) DOI: 10.33408/2519-237X.2018.2-1.25.
Kamlyuk A.N., Likhomanov A.O. Experimental investigations of the influence of the structural elements of sprinklers on the expansion rate of air-mechanical foam. Journal of Civil Protection, 2017. Vol. 1, No. 2. Pp. 167–177. (rus) DOI: 10.33408/2519-237X.2017.1-2.167.
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