Ultrafine Spray of Gas-Water Compositions Investigation for Fire Extinguishing Systems


Annotation:

The analysis of information about domestic and foreign installations of the volumetric fire-extinguishing with gas-water compositions is carried out. Pneumoacoustic sprayers of original design were developed, which make it possible to obtain a gas-water composition containing fire-extinguishing gas and water droplets of the ultrafine spray (10–60 microns).

It is shown that gas-water compositions combine the advantages of fire-extinguishing gas and fine-sprayed water, since the volumetric method of gas fire-extinguishing and the cooling effect of water are preserved. The deposition (movement) of drops of the gas-water composition occurs together with the fire-extinguishing gas; therefore, the gas-water composition of the ultra-dispersed spray can be conventionally considered as a whole, i.e., new extinguishing agent.

It is noted that the most promising is the application of gas-water compositions in the extinguishing of solid smoldering materials. 

In this case, when designing domestic fire-extinguishing installations, the amount of gas can be reduced by 20% or more, and the elimination of smoldering can be achieved by cooling with water from the gas-water composition. At the same time, the fire-extinguishing environment suitable for breathing for at least 3 minutes is formed in the room.

The influence of gas in the gas-water composition on the dispersion of water droplets is studied. The sedimentation rate of water droplets in the gas-water composition was estimated. The droplet dispersion was measured by laser diffraction using the Malvern Spraytec system. It is shown that the substitution of nitrogen for argon or gas composition Argonite in the gas-water composition does not significantly affect the dispersion of droplets. Sedimentation of ultrafine spray water droplets in the volume of the room occurs within a few minutes. Nitrogen has the best characteristics for use in the gas-water compositions. 

Conducted studies make it possible to conclude that the installations based on domestic gas-water compositions allow for import substitution of the foreign analogues certified in Russia.

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DOI: 10.24000/0409-2961-2021-7-60-65
Year: 2021
Issue num: July
Keywords : experiment fire extinguishing system gas-water composition pneumoacoustic sprayer dispersion fine-sprayed water
Authors:
  • Kazakov A.V.
    Kazakov A.V.
    Cand. Sci. (Eng.), Department Head FGBU VNIIPO of EMERCOM of Russia, Balashikha, Russia
  • Smirnov N.V.
    Smirnov N.V.
    Cand. Sci. (Eng.), Lead Researcher, netsend@yandex.ru FGBU VNIIPO of EMERCOM of Russia, Balashikha, Russia
  • Gladilin A.V.
    Gladilin A.V.
    Dr. Sci. (Eng.), General Director — Science Leader JSC «AKIN», Moscow, Russia