EFFICIENCY OF SPRAYED WATER AIR JETS OF A FAN TYPE IN THE AREA OF THE IMPACT OF DIFFUSION FLAME

Abstract

The possibility of using fan-type water jets in the vertical plane to protect against the heat flux of the flame diffusion torch, as well as in the horizontal plane for extinguishing grassland forest fires, has been established. Various nozzle nozzles are considered, which are used in solving the problem of creating a vertical water screen in the form of a spray water jet of fan type for protection against the heat flow of tanks with a capacity of 500 m3 to 2000 m3, as well as to create a spray water jet in a horizontal plane for extinguishing forest grassroots spread. It has been found out that in the detailed examination of compact and sprayed water jets, two phases can be observed: compact (active) and sprayed (passive). In all cases, the use of these jets for the cooling, irrigation and protection of physical objects from the thermal impact of the flame torch use only the active phase, since, as experiments in polygonal conditions show, only this phase of the jet is a continuous flow and therefore fully performs the function of cooling or absorption (shielding) of thermal energy. When extinguishing grassland forest fires, this factor is not critical, so a full-length water jet with the maximum water spray sector is actively used. It is established that the method described in the article allows to reduce the number of personnel of the units of the fire and rescue service involved in the creation of a water protection system, and the average consumption of water by 4.5 and 4.6 times, respectively, by 77% and 78 % less than the traditional tank cooling method. Sprayed water jet created with the help of a special nozzle and mounted as a vertical fan-shaped water curtain, when reoriented to a horizontal plane, is capable of affecting a burning area of ​​a grassland forest fire up to 30 m long with a water spray sector of 47 °.