RU2763285C2 - Fire extinguishing aerosol generator - Google Patents

Abstract

FIELD: fire-fighting equipment.

SUBSTANCE: invention relates to fire-fighting equipment, in particular to primary means of fire extinguishing; it can be used for local fire extinguishing. A fire extinguishing aerosol generator (hereinafter – FEAG), made in the form of a cylindrical or prismatic case, includes a charge of an aerosol-forming or gas-forming composition (hereinafter – AFC). FEAG case has a diaphragm with nozzle holes separating an AFC charge unit from a hollow chamber, in which a coaxial pipe of a smaller diameter than the case is installed, while nozzle holes are located inside the projection of the coaxial pipe on the diaphragm, and the coaxial pipe is made with ejection holes in the lower part of its case and connected to the diaphragm. In the second embodiment, at least one gap is formed between the coaxial pipe and the diaphragm.

EFFECT: reduction in the temperature of a high-temperature fire extinguishing aerosol jet, while expanding the functionality of the use of FEAG and increasing the fire extinguishing capability of aerosol.

2 cl, 3 dwg

Description

The invention relates to fire fighting equipment, in particular, to primary fire extinguishing means and can be used for local fire extinguishing.

Currently, fire extinguishing aerosol generators (GOA) are increasingly used as primary fire extinguishing equipment. Their advantages (higher efficiency in comparison with freons, low toxicity, lack of corrosive activity in relation to metals, dielectric properties) make them an effective means for extinguishing various objects located in hermetic and conditionally hermetic volumes: electrical cabinets, server rooms, cable channels , technical compartments of vehicles, etc.

However, the problem of the widespread use of GOA is the high temperature of the gas-aerosol jet leaving the generator (more than 500 ºС for type 1 generators).

There are known cases of secondary fires in the process of application and false operation of the GOA.

This problem is solved by lowering the combustion temperature of an aerosol-forming or gas-forming composition (AOS) and cooling its combustion products - a fire-extinguishing gas-aerosol jet.

From the prior art, various mechanisms for cooling a fire-extinguishing gas-aerosol jet are known.

An aerosol generator is known (patent RU2142836), which includes pyrotechnic checkers, an igniter, a receiver, and is made in the form of rigidly connected, coaxially mounted, perforated cylinders of the cooling unit and housing, which are equipped with thermal protective shells made of a hardening material (building gypsum, foam concrete, etc.). ).

The output reverse channel between the housing and the casing of the cooling unit is closed by a cover with nozzles, which acts as a diaphragm. Cooling of the gas-aerosol mixture occurs due to the passage through the described annular labyrinth and the ejector of the axial nozzle.

The disadvantage of this device is the complexity of the design and increased hydraulic resistance to gas-aerosol flow, which entails the danger of high pressure in the receiver and the need for thermal protection of the body due to the high combustion temperature of the aerosol-forming composition (AOS).

In patents RU193526 and RU153729, the aerosol jet is cooled in a mixing chamber, into which the formed fire-extinguishing aerosol or high-pressure gas enters from the combustion chamber through the working nozzle. The mixing chamber is formed by the walls of the cylindrical body of the fire-extinguishing aerosol generator and is made in the form of an ejector with side nozzle holes for sucking atmospheric air from the outside into the mixing chamber, thereby forming a directed and cooled flow of a fire-extinguishing gas-aerosol jet at the outlet.

The disadvantage of this design is the need to ensure a uniform suction of air along the generatrix of the housing, that is, to maintain the distance between the generator and the enclosing structures, which is sometimes difficult and sometimes impossible. In conditions of dense mounting of structural elements (for example, in electrical cabinets, engine compartment of a car), symmetrical lateral air inflow is practically excluded.

Known generator fire extinguishing aerosol (RU2189840), which is a cylindrical or prismatic housing with outlets for fire extinguishing aerosol, arranged in one or more rows, and the minimum distance H between the outlets refers to the diameter of the outlet D as N/A = 0.5- 4. Inside the case there is a charge from an aerosol-forming composition (AOS) and an igniter. Branch pipes with ejection holes are made on the body next to the outlet holes, located parallel to the direction of the jet of the outflowing aerosol. In the process of AOS combustion, the released fire-extinguishing aerosol flows out through the outlet holes in several separate jets, which are mixed with air sucked in through the ejection holes of the nozzles and partially cooled.

The disadvantage of this technical solution is the complexity of the design and multidirectional gas-aerosol jets.

An aerosol type fire extinguisher is known (patent JP2011062340), which includes a cylindrical body with side nozzle holes, in the lower part of which there is a solid charge of an aerosol-forming composition. The upper part of the cylindrical housing is a hollow chamber formed by the walls of the housing and separated from the lower part by a diaphragm with nozzle holes for the exit of the aerosol jet.

The cylindrical body is placed in an outer cylindrical container, between the walls of which an annular space is formed, which serves as a thermal protection of the container, and through which atmospheric air is sucked in by the ejector of the inner cylinder.

The disadvantages of this device is the complexity of the design, high material consumption, increased dimensions. These shortcomings are due to:

a) the use of high-temperature fuel, which leads to the use of reinforced thermal insulation, the air gap of the annular space and the installation of additional heat-shielding elements of the AOC container;

b) low efficiency of the ejector, since the nozzle holes for suction of atmospheric air are located in the upper part of the cylinder at a large distance from the nozzle block, which leads to a decrease in the ejection coefficient. In addition, the aerosol jet has a large diameter and the admixture of air will touch only the surface layer of the aerosol stream.

This technical solution is the closest analogue to the claimed invention and can act as a prototype.

The problem to be solved by this invention is the creation of a GOA design that provides effective cooling of a high-temperature fire-extinguishing aerosol jet without additional cooling components while achieving high fire-extinguishing efficiency, safe aerosol impact on protected premises and simplicity of design.

The technical result of the invention is to reduce the temperature of the high-temperature fire-extinguishing aerosol jet while expanding the functionality of the use of GOA and increasing the fire-extinguishing capacity. At the same time, the design of the proposed GOA is simple and reliable due to the absence of additional cooling components and the absence of ejection holes on the device body, which can be blocked by external objects and disturb the symmetrical lateral air inflow, which generally significantly reduces the cost of production of the proposed generators.

The achievement of these results is carried out by means of a fire-extinguishing aerosol generator, the implementation of which is presented in two versions, which form a group of inventions.

In the first embodiment, the fire-extinguishing aerosol generator is made in the form of a cylindrical or prismatic housing, which includes a charge of an aerosol-forming or gas-forming composition and a launch unit, characterized in that a diaphragm with nozzle holes is installed in the GOA housing, separating the AOC charge block, forming a hollow chamber in the upper part of the GOA body, in which a coaxial pipe of a smaller diameter than the GOA body is installed, while the coaxial pipe is made with ejection holes in the lower part of its body and is connected to the diaphragm.

In the second embodiment, the fire-extinguishing aerosol generator is made in the form of a cylindrical or prismatic housing, which includes a charge of an aerosol-forming or gas-forming composition and a launch unit, characterized in that a diaphragm with nozzle holes is installed in the GOA housing, separating the AOC charge block, forming a hollow chamber in the upper part of the GOA body, in which a coaxial pipe of a smaller diameter than the GOA body is installed, while the coaxial pipe is aligned with the diaphragm with an annular gap formed between the lower part of the coaxial pipe and the diaphragm.

In both versions, the nozzle holes of the diaphragm are located inside the transverse plane of the coaxial pipe, if it is projected onto the diaphragm. The coaxial pipe may be in the form of a cylinder or a prism.

The unity of the invention is due to the general idea, in which the fire-extinguishing aerosol generator, made in the form of a cylindrical or prismatic body, which is divided by a diaphragm with nozzle holes into two parts - one contains a charge of an aerosol-forming or gas-forming composition, and the second forms a hollow chamber in the upper part of the GOA body, in which a coaxial pipe of a smaller diameter is installed than the GOA body. In one embodiment, ejection holes are made on the coaxial pipe as close as possible to the diaphragm. In this embodiment, the coaxial pipe along its perimeter is connected to the diaphragm. In another embodiment, a gap is formed between the coaxial pipe and the diaphragm, which acts as an ejection hole. In this case, the gap can be made annular around the entire perimeter of the coaxial pipe. In this case, the coaxial pipe is fixed on the inner wall of the GOA case. Also, a gap can be made at the junction of the coaxial pipe and the diaphragm, and there may be several such gaps.

The invention will now be described with reference to the drawings:

figure 1 - General diagram of the first version of the generator fire-extinguishing aerosol (GOA), top view, where 1 - housing GOA, 2 - AOS charge, 3 - start node, 4 - diaphragm, 6 - coaxial pipe made in the form of an ejector, 7 - ejection holes of the coaxial pipe, 8 - chamber of the coaxial pipe, 9 - outlet nozzle of the coaxial pipe, 10 - annular cavity formed by the walls of the GOA body and the coaxial pipe;

figure 2 - General diagram of the second version of the generator fire-extinguishing aerosol (GOA), top view, where 1 - housing GOA, 2 - AOS charge, 3 - start node, 4 - diaphragm, 6 - coaxial pipe, 8 - coaxial pipe chamber, 9 - outlet nozzle of the coaxial pipe, 10 - annular cavity formed by the walls of the GOA body and the coaxial pipe, 11 - gaps formed between the lower part of the coaxial pipe and the diaphragm, 12 - supports for installing the coaxial pipe;

figure 3 - General diagram of the generator fire-extinguishing aerosol (GOA). front view, where 5 - nozzle holes of the diaphragm for the exit of fire extinguishing aerosol.

GOA is a cylindrical or prismatic body (1), in the lower part of which there is a charge of a low-temperature flameless aerosol-forming or gas-forming composition (2) and a launch unit (3). The upper part of the GOA body is a hollow chamber formed by the walls of the GOA body (1) and is separated from its lower part by a diaphragm (4) with nozzle holes for the exit of fire extinguishing aerosol or gas (5). The diaphragm (4) is fixedly fixed in the body of the GOA (1).

In the first version of the GOA (figure 1) a coaxial pipe (6), smaller in diameter than the GOA body (1), is made in the form of an ejector with ejection holes (7) in the lower part of its body and is rigidly connected to the diaphragm (4) along the entire perimeter of the pipe.

The ejection holes (7) are made as close as possible to the diaphragm (4). This is due to the fact that in the lower part near the nozzle holes, the jet exits with the highest pressure. This creates a large pressure difference with atmospheric air and air is sucked in with greater intensity through the ejection holes.

In the second version of the GOA (figure 2), a coaxial pipe (6) of a smaller diameter than the GOA body (1) is aligned with the diaphragm (4) with gaps (11) formed between the lower part of the coaxial pipe (6) and the diaphragm ( 4), and the coaxial tube is fixed in the GOA body at a minimum distance from the diaphragm.

The coaxial pipe can be installed in the hollow chamber of the upper part of the GOA housing using a screw connection or fixing supports attached to the diaphragm or walls of the GOA housing.

The launch unit (igniter) in the proposed versions of the GOA can be of any type known from the prior art.

Generator fire-extinguishing aerosol (GOA) works as follows.

When a starting pulse is applied to the launch unit (3), a charge is ignited from a low-temperature flameless aerosol-forming or gas-forming composition (2), upon combustion, a fire-extinguishing aerosol-gas or gas mixture is formed, which, under high pressure, exits through the outlet nozzle holes (5) of the diaphragm (4) and enters the chamber of the coaxial pipe (8).

The formed high-temperature aerosol jet flows out of the outlet nozzle of the coaxial pipe (9) under high pressure, as a result of which atmospheric air is sucked through the annulus (10) and through the ejection holes (7) of the coaxial pipe (see Fig. 1) or through the gaps ( 11) see fig. 2 enters the chamber of the coaxial pipe (8), where the active mixing of the fire-extinguishing aerosol or gas jet with air takes place, which further reduces the temperature of the gas-aerosol jet. In addition, the sucked-in air, passing through the annulus (10), effectively cools the GOA body.

It should be noted that the air enters the chamber of the coaxial pipe in the absence of obstacles in the way of its entry, since the air enters from the end from which the aerosol-gas fire-extinguishing jet propagates, and the conditions for the use of GOA exclude any obstacles in the path of the fire-extinguishing jet. As a result, a symmetrical lateral air inflow and symmetrical/uniform cooling of the jet and the GOA body are created.

Thus, due to a significant decrease in the temperature of the generated fire-extinguishing aerosol-gas jet, the proposed GOA, with a simple design, has an increased extinguishing efficiency, minimizes the risk of damage to protected objects, and eliminates injuries during use and false alarms.

Claims (2)

1. A fire-extinguishing aerosol generator (GOA), made in the form of a cylindrical or prismatic body, including a charge of an aerosol-forming or gas-forming composition (AOS), characterized in that a diaphragm with nozzle holes is installed in the GOA body, separating the AOS charge unit from a hollow chamber, in which a coaxial pipe of a smaller diameter than the body is installed, while the nozzle holes are located inside the projection of the coaxial pipe onto the diaphragm, and the coaxial pipe is made with ejection holes in the lower part of its body and is connected to the diaphragm. 2. A fire-extinguishing aerosol generator (GOA), made in the form of a cylindrical or prismatic body, including a charge of an aerosol-forming or gas-forming composition (AOS), characterized in that a diaphragm with nozzle holes is installed in the GOA body, which separates the AOS charge unit from the hollow chamber, in which a coaxial pipe of a smaller diameter than the housing is installed, the nozzle holes are located inside the projection of the coaxial pipe onto the diaphragm, and at least one gap is formed between the coaxial pipe and the diaphragm.

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