WO2005084816A1

WO2005084816A1 - Fire extinguishing apparatus and atomizer using a swirler

Info

Publication number: WO2005084816A1
Application number: PCT/RU2005/000079
Authority: WO
Inventors: Andrey Leonidovich Dushkin; Alexander Vladimirovich Karpyshev; Aleksey Nikolaevich Protasov
Original assignee: Andrey Leonidovich Dushkin; Karpyshev Alexander Vladimirov; Aleksey Nikolaevich Protasov
Priority date: 2004-03-10
Filing date: 2005-02-25
Publication date: 2005-09-15
Also published as: TW200631619A; RU2254155C1; TWI287463B

Abstract

A fire extinguishing apparatus has a fluid storage tank, a fluid supplying system, and a fluid atomizer. The fluid atomizer includes a nozzle (12) equipped with a profiled channel, a cylindrical chamber, and a fluid flow swirler (17). Guiding elements (18) of the swirler (17) are uniformly distributed in an azimuth over a cross section of the cylindrical chamber. The edges of adjacent guiding elements (18) define through apertures in a projection onto a cross section of the cylindrical chamber. A diaphragm (15) is located upstream of the swirler (17) and is provided with apertures (16) arranged opposite the through apertures formed in the swirler (17). The azimuthal movement of the diaphragm (15) relative to an axis of symmetry of the cylindrical chamber changes the mutual arrangement of the apertures (16) of the diaphragm (15) and apertures of the swirler (17). This results in changing of a cone angle of an atomized gas-droplet flow spray.

Description

FIRE EXTINGUISHING APPARATUS AND ATOMIZER USING A SWIRLER

Field of the invention The invention relates to fire extinguishing means and to fluid atomizing means and methods. Fluid atomizers may be used as part of fire fighting devices for various purposes. The invention more particularly deals with an embodiment of a fluid atomizer used as part of portable (backpack) type fire fighting equipment. Background of the invention Portable fire extinguishing apparatuses currently utilized are furnished with various types of fluid atomizers. For example, the patent RU 2132752 Cl (IPC-6 B05B 7/04, published 10.07.1999) describes a portable fire extinguishing apparatus for generation of a long-distance gas-droplet flow. A fluid atomizer used as part of such an apparatus includes a profiled gas-dynamic nozzle, a fluid and gas mixing chamber, a fluid stream atomizing device for atomizing a fluid flow to be supplied to the mixing chamber, and a system for supplying fluid and gas to the mixing chamber. A fire extinguishing fluid is stored in a storage tank of the given apparatus and is forced from the storage tank by the action of a pressurized gas during operation of the apparatus. An apparatus of the known prior art allows high-velocity gas-droplet flows to be projected to a distance of up to 12 m. However, it should be born in mind that a gas-dynamic process for acceleration of fluid droplets in a gas flow imposes restrictions to an angle of expansion of the generated gas-droplet flow at the outlet end of a nozzle. Attachment to a gas dynamic nozzle of complementary atomizers (spray jets) allows a cone angle of the generated gas-droplet flow spray to be increased to 120°, however a distance of projecting the gas- droplet flow is significantly reduced. The given discrepancy does not allow a known fire extinguishing apparatus of the prior art to be implemented for extinguishing a wide range of fire sites. For example, extinguishing of flammable liquids by means of a narrow directed long-distance gas-droplet flow does not provide for efficient fire extinguishing and safe operation of a fire-fighter owing to fluid splashing. The employment of complementary spray jets in the known apparatus of the prior art allows atomized gas-droplet flows with a large spray cone angle to be generated, although in this situation the distance of projecting a fire extinguishing substance is substantially reduced to thereby make the extinguishing of high- intensity fires caused by the combustion of flammable liquid materials impracticable. A diversity of means is presently used for adjustment of parameters of a gas-droplet flow. In particular, the published patent application US 2003/0047327 Al (IPC-7, A62C 2/00, published 13.03.2003) discloses a portable fire extinguishing apparatus including a fluid atomizer equipped with an in-flow air and fluid mixing regulator. The given regulator has an effect only upon an amount of turbulence of a fluid flow and, consequently, upon generation of foam in the flow of fire extinguishing substance. The effect of an amount of flow turbulence upon an angle of expansion of a flow of fire extinguishing substance may be exhibited under predetermined conditions, however this effect is not disclosed in the Icnown source of information. The closest analog of the present invention is a portable fire extinguishing apparatus disclosed in the patent US 5623995 (IPC-6 A 62C 25/00, published 29.04.1997). The portable fire extinguishing apparatus of the prior art includes a storage tank for a fire extinguishing fluid, a system for supplying the fluid under pressure, a fluid flow swirler (turbulizer), and a foam flow atomizer. The fluid supply system of the given apparatus is configured as a diaphragm pump. The fluid flow swirler is provided in a cylindrical mixing chamber, into which a fluid containing a foam generating agent is supplied in axial direction and a gas under excessive pressure is supplied in tangential direction. Intensive mixing of the fluid and gas in the channels of the mixing chamber between guiding elements results in an intensive mechanical foam generation. The foam generated is further delivered through a flexible hose to the atomizer configured as a nozzle provided with a profiled channel. A pressurized gas is employed in the given apparatus as a working medium for driving a diaphragm pump and for supporting a most efficient turbulization of the fluid flow. The apparatus under consideration as well as other embodiments of the prior art do not provide for adjustment of an angle of expansion of the generated flow of fire extinguishing substance with a predetermined droplet atomization extent in the flow and a distance of projecting a gas-droplet flow. Various types of fluid atomizers are presently known, which may be utilized for the generation of gas-droplet stream flows in fire fighting systems. The patent application US 2003/0047327 (IPC-7 A62C 2/00, published 13.03.2003) describes a fluid atomizer configured as a nozzle equipped with a profiled channel. The nozzle inlet end is fluidly communicated with a supply line via a cylindrical chamber and a cylindrical channel having a minimal passage section, said cylindrical chamber and cylindrical channel being arranged in succession. The nozzle is fitted with an axial cylindrical insert adjustable in length and configuration. Displacement of the adjustable insert with respect to a diverging part of the nozzle causes variation in the fluid flow velocity and, accordingly, in the flow turbulization level and foam generation efficiency. The flow turbulization in the known embodiment of the prior art is also regulated with the help of an adjustment screw by advancing its pointed end into the fluid flow. It should be noted that the above described embodiment lacks means for adjustment of a cone angle of the generated gas-droplet flow spray. The closest analog of a fluid atomizer of the present invention is an atomizer described in the Author's certificate USSR No. 292678 (IPC AOlm 7/22, the Description published 22.04.1971). The atomizer includes a nozzle equipped with a profiled channel, a cylindrical chamber connected at its one end to the nozzle inlet, and a fluid flow swirler. The profiled channel of the atomizer consists of two parts: a converging tube and a diffuser. The fluid flow swirler is housed within the nozzle diffuser cavity and is configured as a deflection plate with two acute edges arranged at an angle of 30° with respect to one another. On supplying of fluid under pressure into the atomizer, the fluid flow is accelerated in the converging tube to abut against the acute edges of the swirler, this resulting in splitting of the fluid flow into small droplets and acceleration of the produced gas-droplet flow in the nozzle diffuser. The resultant gas-droplet flow discharged from the nozzle outlet end is configured as a cone spray. However, the given apparatus of the prior art does not provide for the generation of high-velocity gas-droplet flows having uniform droplet sizes since the deflection plate housed within the converging tube cavity imparts additional resistance to the fluid flow. Therefore, despite an improved uniformity of the gas-droplet flow in a spray, the fluid flow velocity is substantially reduced. It should be also pointed out that the parallel oriented acute edges of the swirler deflect the generated flow only in one direction, namely, perpendicular to the swirler edge surfaces. As a result of these, the gas-droplet flow spray is expanded at the nozzle outlet end in one direction. The resultant flow spray has an elliptical section. The atomizer of the prior art has therefore limitations as to practical application due to non-uniform expansion of a gas-droplet flow. Moreover, the apparatus of the prior art does not provide the possibility for adjustment of a cone angle of gas-droplet flow spray while keeping the velocity of fluid particles directed to a fire site. Disclosure of the invention The present invention is aimed at providing the adjustment of a cone angle of a generated gas-droplet flow spray at a predetermined distance of projecting a fire extinguishing substance. The object of the invention is to facilitate the adjustment of a cone angle of a generated gas-droplet flow spray in terms of the following conditions: on varying a cone angle of a gas-droplet flow spray, an axial velocity of fluid droplets would not be significantly reduced (accordingly, a distance of projecting a fire extinguishing or any other substance would not be significantly reduced); on varying a cone angle of a flow spray, the uniformity of a gas-droplet flow with regard to droplet sizes should be kept; on varying a cone angle of a spray of gas-droplet flow, a fluid flow velocity through the nozzle must be kept. The technical result obtained through the solution of tasks set with regard to a portable fire extinguishing apparatus is an improved efficiency in extinguishing various classes of fires, including those caused by the inflammation of flammable liquids. The claimed technical result is achieved with the use of a portable fire extinguishing apparatus and a fluid atomizer designed in accordance with the present invention. The portable fire extinguishing apparatus comprises a storage tank for a fire extinguishing fluid, a system for supplying a pressurized fluid, a fluid flow swirler equipped with guiding elements, and a fluid atomizer coupled through a supply line to the storage tank.

The fluid atomizer includes a nozzle with a profiled channel and a cylindrical chamber one end part of which is connected to the nozzle inlet. According to the present invention, the fluid flow swirler is located upstream of the other end part of the cylindrical chamber, the number of the guiding elements of the swirler is at least three, and the guiding elements are uniformly distributed in an azimuth of the cylindrical chamber cross section. The edges of the adjacent guiding elements define through apertures in a projection on a cross section of the cylindrical chamber. Located upstream of the swirler in the course of fluid flow is a diaphragm provided with apertures arranged opposite the through apertures of the swirler, with the structure of the atomizer enabling an azimuthal movement of the diaphragm relative to an axis of symmetry of the cylindrical chamber. The combination of the above described essential features of the invention allows the mode of generation of a narrow directed gas-droplet flow to be changed-over by aligning the apertures in the diaphragm with the apertures in the swirler to the mode of generation of a wide gas-droplet flow by providing an azimuthal shift of the apertures in the diaphragm with respect to the apertures in the swirler. The given invention is characterized in that change in the mode of generation of a gas-droplet flow (shape of stream) does not substantially reduce a distance of projecting a stream flow and a fluid flow velocity and does not change the uniformity of the flow with regard to the fluid droplet sizes. The given effect is due to the employment of a cylindrical expansion chamber interposed between the inlet of the profiled channel of the nozzle and the guiding elements of the swirler. Another essential feature of the apparatus is the availability of the diaphragm equipped with passage apertures and adapted for azimuthal movement. The diaphragm is positioned directly before the guiding elements of the swirler. Together with the flow swirler having through apertures in a projection on the cross section of the cylindrical chamber, the diaphragm structurally defines a regulator for adjusting an angle of fluid flow turbulence relative to an axis of symmetry of the cylindrical chamber. Thus, a fluid flow with a peripheral part having a tangential velocity component is generated in the cylindrical chamber. The generated fluid flow with the turbulent peripheral part is thereafter delivered to the inlet of the profiled channel of the nozzle. The azimuthal movement of the diaphragm results in shifting of its passage apertures with respect to the through apertures interposed between the guiding elements of the swirler and, as a consequence, in changing of an angle of turbulence of the fluid flow. Acceleration of the fluid flow generated in the profiled channel of the nozzle results in the atomization of the fluid flow and production of a long-distance gas-droplet flow. The spray cone angle of the gas- droplet flow is a function of the angular shifting of the apertures in the diaphragm and swirler. In a preferred embodiment of the invention, the length L of the cylindrical chamber is selected on condition that L < 14d_c, where d_c is diameter of a passage section of the cylindrical portion of the nozzle. It may be also advantageous that the diameter D of the cylindrical chamber be selected on condition that D > 3d_c, where d_c is diameter of a flow-passage section of the cylindrical portion of the nozzle. With the above conditions, the minimal reduction in the distance of projecting the gas- droplet flow and in the fluid flow velocity has been exhibited and minimal changes in the uniformity of flow with regard to droplet sizes have occurred after adjustment of the cone angle of the generated spray of gas-droplet flow. The achieved technical result exhibits itself to the maximum extent with the employment of swirler guiding elements having a concave surface. For increasing a distance of projecting the generated gas-droplet flow, the nozzle used has a profiled channel defined by a converging conical portion, a cylindrical portion, and a diverging conical portion, said portions being arranged in succession. A nozzle with a profiled channel defined by a converging conoid-shaped portion, a converging conical portion, a cylindrical portion and a diverging conical portion can also be used, said portions being arranged in succession. In order to reduce the apparatus manufacture expenses, a short nozzle free from a diverging conical portion may be used. In this case, a profiled channel of the nozzle is formed of a converging conoid-shaped portion, a converging conical portion and a cylindrical portion, said portions being arranged in succession. The obtained technical result may be also achieved through the utilization of a fluid atomizer including a nozzle with a profiled channel, a cylindrical chamber having one end part connected with the nozzle inlet, and a fluid flow swirler. According to the present invention, the fluid flow swirler is located upstream of the other end part of the cylindrical chamber, the selected number of guiding elements of the swirler is at least three, and the guiding elements are uniformly distributed in an azimuth of a cross section of the cylindrical chamber. The edges of adjacent guiding elements form through apertures in a projection on a cross section of the cylindrical chamber. Located upstream of the swirler in the course of fluid flow is a diaphragm equipped with apertures arranged opposite the through apertures in the swirler. The structure of the atomizer provides for azimuthal movement of the diaphragm with respect to an axis of symmetry of the cylindrical chamber. The combination of the above essential features characteristic of the structure of the fluid atomizer allows gas-droplet streams to be generated with an adjustable cone angle of a gas-droplet flow spray at a predetermined distance of projecting a fluid flow, a fluid flow velocity and uniformity of the flow with regard to drop sizes, when the present invention is utilized. In a preferred embodiment the length L of the cylindrical chamber is selected on condition that L < 14d_c, where d_c is diameter of a passage section of the nozzle cylindrical portion. The diameter D of the cylindrical chamber is selected on condition that D > 3d_c, where d_c is diameter of a passage section of the cylindrical portion of the nozzle. The guiding elements of the swirler may be concave in shape. The profiled channel of the nozzle may be formed of a converging conical portion, a cylindrical portion and a diverging conical portion, said portions being arranged in succession. A nozzle of the embodiment most preferable is provided with a profiled channel formed of a converging conoid-shaped portion, a converging conical portion, a cylindrical portion and a diverging conical portion, said portions being arranged in succession. An embodiment of the invention is also possible, where the atomizer nozzle is free from a diverging conical portion. In this case, the profiled channel of the nozzle is formed of a converging conoid-shaped portion, a converging conical portion, and a cylindrical portion, said portions being arranged in succession. Brief description of drawings The present invention is explained by an example of a particular embodiment of a portable fire extinguishing apparatus and a fluid atomizer as part of it, and accompanying drawings, including: Fig. 1 is a schematic diagram of a portable fire extinguishing apparatus with a fluid atomizer; Fig. 2 is a longitudinal section of a fluid atomizer with a local view of a fluid flow swirler; Fig. 3 is a cross sectional view of a fluid atomizer in plane A-A at the site of arrangement of a device for restricting an azimuthal movement of a swirler relative to a diaphragm; Fig. 4 is a cross sectional view of a fluid atomizer in plane B-B at the site of arrangement of a swirler; Fig. 5 is a side view of a swirler with flat guiding elements; Fig. 6 is a side view of a swirler with concave guiding elements. Description of a preferred embodiment of the invention A portable fire extinguishing apparatus illustrated in Fig.l includes a water storage tank (container) 1 intended for placement onto a fire-fighter's (user's) backpack. The apparatus is also furnished with a displacement-type fluid supplying system including a balloon 2 with a pressurized gas (air) contained therein, a line for supplying a pressurized gas to a gas cavity of the storage tanlc 1, said line being equipped with a check valve 3 and a gas reducer 4. The fire extinguishing apparatus is further provided with a fluid atomizer 5 mounted on a handle 6 with a trigger-type valve mechanism 7. In the embodiment under consideration, the fluid atomizer is an integral part of the fire extinguishing apparatus, however the given atomizer may also function as an independent unit in the structure of apparatuses of any other designation. The atomizer 5 is coupled to the storage tanlc 1 via a supply line 8. Water is supplied to the fluid atomizer 5 upon pressing by the fire-fighter on the trigger-type mechanism 7. The storage tanlc 1 is fluidly communicated with a charging manifold through a charging valve 9. A charging valve 10 and a pressure meter 11 are set on the balloon 2. The fluid atomizer illustrated in Fig. 2 is comprised of a nozzle 12 with a profiled channel, a sleeve 13 with a cylindrical chamber, and a connection pipe 14. The connection pipe 14 is furnished with a built-in diaphragm 15 having four apertures 16. A swirler 17 with guiding elements 18 is disposed at the input to the cylindrical chamber of the sleeve 13, near 5 an inlet end of the chamber. The four guiding elements 18 are uniformly distributed in an azimuth of a cross section of the cylindrical chamber. The number of the guiding elements 18 may vary from three to six in different embodiments of the fluid atomizer. The nozzle 12 is fixed on the sleeve 13 by means of a captive nut 19. The junction between the nozzle 12 and the sleeve 13 is hermetically sealed with a sealing gasket 20. The0 profiled channel of the nozzle is formed of a converging conoid-shaped portion 21, a converging conical portion 22, a cylindrical portion 23, and a diverging conical portion 24, said portions being arranged in succession. The sleeve 13, in conjunction with the cylindrical chamber, is attached to the connection pipe 14 by means of a captive nut 25 for rotation relative to an axis of symmetry of the5 cylindrical chamber. Rotation of the sleeve 13 relative to the fixed connection pipe 14 is essential in order to provide for azimuthal shifting of the passage apertures 16 of the diaphragm 15 relative to the through apertures 26 defined by the edges of adjacent guiding elements 18 of the swirler 17 (see Fig. 3). In the initial position (before adjustment of the cone angle of a gas-droplet flow spray), the apertures 16 of the diaphragm 15 are arranged opposite o the apertures 26 of the swirler 17, as shown in Fig. 3. Rotation of the sleeve 13 relative to the fixed connection pipe 14 is enabled by locating the sleeve 13 in spaced-apart relation with respect to the surfaces of the captive nut 25 and the connection pipe 14. The junctions are hermetically sealed by means of sealing gaskets 27 and 28.5 The azimuthal shift of the apertures 16 in the diaphragm 15 relative to the apertures 26 in the swirler 17 within the predetermined range of from 0° to 45° is provided by means of an angular movement restricting device. In an embodiment of the atomizer under consideration, a protrusion 29 on the surface of the sleeve 13 functions as an angular movement restricting device. The protrusion 29 is set in a slot 30 formed in an end part of the connection pipe 14 for o free movement to the extreme angular positions (see Figs 2 and 3). The guiding elements 18 of the swirler 17 are uniformly distributed in an azimuth of a cross section of the cylindrical chamber provided in the sleeve 13 (see Fig. 4). The apertures 26 of the swirler 17, which are defined by the edges of the adjacent guiding elements 18, are made rectangular in shape, with apertures 26 being of through-type in a projection onto a cross section of the cylindrical chamber of the sleeve 13 (see Fig. 4). The surface of the guiding elements 18 in the swirler 17 may be flat, as shown in Fig. 5, or concave, as shown in Fig. 6. When the guiding elements 18 with flat surfaces are used, an optimal inclination angle of the guiding surface with respect to a longitudinal axis of symmetry of the swirler 17 and the sleeve 13 is 45° (see Fig. 5). An embodiment most preferable is a swirler 17 with guiding members provided with a concave working surface (see Fig. 6). In this case, the hydraulic losses for turbulization of a fluid flow in the cylindrical chamber are reduced. In an embodiment of the swirler 17 shown in Fig. 6, a flat edge 31 with an inclination angle of 45° with respect to an axis of symmetry of the swirler is provided on a reverse side of the guiding element 18. The use of such an. edge allows hydraulic losses to be reduced owing to the elimination of abrupt deviations in the swirler channel, which is provided between the adjacent guiding elements 18. In an example of the embodiment of the invention under consideration the sizes of the cylindrical chamber of the sleeve 13 are selected in terms of the following conditions depending upon diameter d_c of a passage section of the cylindrical portion 23 of the nozzle 12 (see Fig. 2): length L of the cylindrical chamber is 11 d_c (L < 14d_c); diameter D of the cylindrical chamber is 4d_c (D > 3d_c). With the selected value d_c=4 mm for the diameter of the cylindrical portion 23 of the nozzle 12, the length L and the diameter D of the cylindrical chamber are 44 mm and 16 mm, respectively. The operation of the fire extinguishing apparatus and the fluid atomizer as part of the apparatus is provided in the following manner. Before the first employment of the fire extinguishing apparatus, the storage tank 1 is charged with a fire extinguishing fluid. The fire extinguishing fluid used is water containing foam generators and other chemical additives causing an increase in fire fighting capability. The storage tank 1 is charged by means of the charging valve 9. The volume of fluid for the backpack-type fire extinguishing apparatus is about 12 / with the total volume of the storage tank of 15 /. The balloon 2 is charged through the charging valve 10 with a pressurized air, which is supplied from a compressor until the pressure of (150 ÷ 300) TO⁵ Pa is set. Thereafter a gas cavity in the storage tanlc 1 is preliminarily supercharged via a compressed gas line. To this end, a check valve 3 is opened and the pressurized gas is delivered to the input of a gas reducer 4. The pressure at the output of the reducer 4 and, accordingly, in the gas cavity of the storage tank 1 is (8- 10) TO⁵ Pa. As a result, a fluid pressure within a predetermined range is set in the fluid cavity of the storage tanlc 1 and in the supply line 8 up to the inlet end of a controllable normally closed valve (not shown in the drawing). The given valve is mounted in the body of the handle 6. The valve is controlled by means of a trigger type mechanism 7. The above pressure level in the fluid supply system for supplying fluid to the atomizer is conditioned by thee required flow velocity of from 0.2 to 0.4 Us of the generated gas-droplet flow. The pressure level in the storage tank 1 is selected with due regard for the hydraulic losses in the supply line 8 and in the fluid atomizer 5. In an example of embodiment of the invention under consideration the gas-droplet flow velocity through the atomizer 5 is correlated to the desired fire fighting capability, which is of essential importance when the atomizer is employed as part of a portable fire extinguishing apparatus. The storage tank 1 and the balloon 2 equipped with a pressurized gas line and fittings are mounted either on the fire-fighter's backpack or in the portable container. The generation of a gas-droplet flow is provided by the fire-fighter using the fluid atomizer 5 attached on the handle 6 and actuated by means of the trigger type mechanism 7. Upon pressing by the fire-fighter on the trigger type mechanism 7, the controllable valve on the handle 6 is opened and the fluid is delivered under pressure of (8 ÷ 10) TO⁵ Pa to the inlet of a connection pipe 14 of the atomizer 5. The vortex of the fluid flow occurs while it passes through the channels defined by the openings 16 of the diaphragm 15 and the guiding elements 18 of the swirler 17. The azimuthal arrangement of the guiding elements 18 of the swirler 17 over the cross section of cylindrical chamber of the sleeve 13 enhances an increase in an amount of turbulization for the most part in the peripheral portion of the fluid flow. Turbulization of a fluid flow may be accomplished with the use of swirlers equipped with guiding elements having various shapes of their surfaces. For example, a swirler 17 with flat guiding elements 18 may be utilized for this purpose (see Fig. 5). The given embodiment of the swirler 17 is simple in manufacture, although the employment of such a swirler is linked to the substantial increase in hydraulic losses. The embodiment of a swirler 17 most preferable includes guiding elements 18 of concave shape (see Fig. 6). Each of the four channels of such a swirler is defined by a concave surface of the guiding element 18 and by a flat edge 31 on the reverse side of an adjacent guiding element. The flat edge 31 has an angle of inclination of 45° with respect to an axis of symmetry of the swirler. The use of the given embodiment of the swirler allows hydraulic losses in the fluid flow to be essentially reduced. The turbulized fluid flow is finally formed in the cylindrical chamber of the sleeve 13. In the cylindrical chamber the fluid flow acquires a predetermined structure, with the central (axial) part of the flow having a maximal axial and minimal tangential velocity component compared to the peripheral part of the flow (adjacent to the wall). In a preferred embodiment of the atomizer, the sizes of the cylindrical chamber are selected under the following conditions. Length L of the chamber is selected on condition that L < 14d_c, where d_c is diameter of a passage section of the cylindrical portion 23 of the nozzle 12. Diameter D of the chamber is selected on condition that D > 3d_c. The above conditions provide for reduction in hydraulic losses and for a predetermined structure of the fluid flow at the input of the nozzle 12. The generated fluid flow is then delivered to the inlet of the nozzle 12 for further acceleration and atomization thereof. The fluid is preliminarily accelerated while passing through a succession of the converging conoid-shaped portion 21 and the converging conical portion 22. In the course of passage of the accelerated fluid flow through the cylindrical portion 23 of the nozzle 12 cavitational bubbles are intensively created in the turbulized fluid flow. Vaporization process in the fluid flow goes on until the latter reaches an inlet end of the diverging conical portion 24 (a diffuser) of the nozzle 12 where the cavitational bubbles intensively grow and collapse. In the course of passage through the portion 24, the fluid flow separates from the nozzle wall, the cavitational bubbles intensively collapse and the resultant tangentially turbulized fluid drops are split. On flowing through the portion 24 of the nozzle 12 a vapor-gas phase is produced in the fluid flow. This results in reduction of the flow density and acceleration of the two-phase flow in the diverging portion of channel of the nozzle 12. The static pressure in the cavity of the diverging conical portion 24 of the nozzle 12 is low and commensurable with a cavitation pressure value. This results in the occurrence of a directed inflow of ambient air into the cavity defined between the gas-fluid flow and the nozzle wall. The countercurrent air flowing along walls of the diverging portion 24 of the nozzle 12 enhances the vortex process. The given event induces an intensive collapsing of the cavities in the fluid flow and splitting of the latter. The result is that a finely dispersed gas- droplet flow is developed, said fluid drops having a tangential flow velocity component. An average size of drops in the generated flow defined as a total volume to drop surface ratio was from 200 to 400 microns, with the size of individual drops in the flow varying from 40 to 400 microns. It should be pointed out that the indicated range of drop sizes in the generated flow is consistent with an optimal range of drop sizes of from 200 to 300 microns, which is most efficient for extinguishing the fires caused by the inflammation of solid flammables. It had been established during experimental tests that the flow generated had various cone angles of spray depending upon a tangential drop velocity value. The shape of a fluid flow spray may be therefore changed tlirough the adjustment of the tangential flow velocity at the inlet of the nozzle. According to the present invention, the tangential fluid flow velocity is adjusted by changing the azimuthal position of the apertures 16 of the diaphragm 15 with respect to the apertures 26 of the swirler 17. The relative azimuthal movement of the apertures is accomplished by the fire-fighter providing an angular shift of the sleeve 13 relative to the comiection pipe 14. Rotation of the sleeve 13 is provided by arranging it in spaced relation with respect to mating structural components. The junctions between the sleeve 13, captive nut 25 and connection pipe 14 are hermetically sealed by means of sealing gaskets 27 and 28. The junction between the sleeve 13 and nozzle 12 is made fixed and is hermetically sealed by means of a sealing gasket 20 which is tightened up by the captive nut 19. The azimuthal movement of apertures 16 and 26 may be accomplished within a restricted range of angles of from 0° to 45°. The extent of angular movement is restricted by the protrusion 29 formed on the sleeve 13, with sleeve 13 being fixed in its the extreme positions by said protrusion in the process of advancement of the sleeve along the wall of the slot 30 formed in the end part of connection pipe 14 (see Fig. 3). In the initial position of the sleeve 13, the apertures 16 are opposed to the apertures 26 of the swirler 17. In this case, the fluid flow is split into individual streams created in the apertures 16 of the diaphragm 15. Upon passage through the diaphragm, part of the streams abut against surfaces of the guiding elements 18 of the swirler 17 while the major part of the streams flow through the apertures 26 without being turbulized. The partly turbulized fluid flow is further directed into the cylindrical chamber of the sleeve 13 where a single flow is created from the individual streams. The fluid pressure at the input section of the nozzle is about 8 TO⁵ Pa. After acceleration and atomization of the fluid flow, an atomized fluid flow with a spray cone angle of about 20° is generated in a profiled channel of the nozzle 12. The distance of projecting the atomized gas-droplet flow is more than 10 m with the fluid flow velocity of from 0.2 to 0.4 //s. A narrow directed fire extinguishing substance flow generated by means of the fluid atomizer may be used for extinguishing the sites of fire caused by the inflammation of solid flammables. In order to extinguish the sites of fire caused by the inflammation of liquid combustibles and highly flammable liquids, a cone angle of the gas-droplet flow spray is to be increased. To do that, the fire-fighter effects angular movement of the sleeve 13 relative to the connection pipe 14 until the protrusion 29 of the sleeve 13 intrudes into the slot 30 to a fixed extreme position. In the indicated position of the sleeve 13, the apertures 16 of the diaphragm 15 are arranged opposite surfaces of the guiding elements 18 of the swirler 17. Some fluid streams flowing through the apertures 16 of the diaphragm 15 are deflected by the surfaces of the guiding elements 18. In this case, the turbulized fluid streams are created in the cylindrical chamber of the sleeve 13 to flow along walls of the chamber. The generated fluid flow having a turbulized peripheral part is discharged into the profiled channel of the nozzle 12 where it is accelerated and atomized. An atomized gas-droplet flow with a spray cone angle of about 30° is generated at the outlet of the nozzle 12. The investigations performed have shown that, despite an increase in the spray cone angle, the uniformity of gas- droplet flow with regard to drop sizes, the flow velocity and the distance of projecting the gas- droplet flow did not substantially change. The employment of the fluid atomizer as part of the fire extinguishing apparatus of the present invention allowed the spray cone angle of the atomized fluid flow to be changed within the range of from 20° to 30°, said changing being provided by the fire-fighter rotating the sleeve 13 of the fluid atomizer. Changing of the cone angle of the gas-droplet flow within the indicated range did not affect the basic parameters of the flow that proved to be consistent with predetermined requirements and, thus, confirmed the achievement of the technical result. Industrial applicability of the invention The invention may be employed in fire fighting systems and as part of processing equipment used for various purposes. In addition to the employment of the fluid atomizer in fire fighting systems, it may be utilized for the combustion of fuels in heat engineering and transport, as well as for moistening of environment and spraying of disinfectants and insecticides. As fire extinguishing means, the invention may be used in stationary and mobile fire fighting installations for fires extinguishing on a variety of objects, such as hospital, library and museum rooms, on ships, aircrafts, as well as for retarding the sites of fire in open space, etc. The above example of an implementation of the embodiment of the invention is preferable, although it does limit any other possible versions of the embodiment based on the claims of the invention which may be utilized with the help of means and methods Icnown for those skilled in the art.

Claims

CLAIMS We claim: 1. A portable fire extinguishing apparatus comprising a storage tanlc (1) with a fire extinguishing fluid contained therein, a system for supplying a fluid under pressure, a fluid flow swirler (17) with guiding elements (18), a fluid atomizer (5) connected through a supply line (8) with said storage tank (1), said fluid atomizer comprising a nozzle (12) with a profiled channel and a cylindrical chamber having one end part connected to an inlet of the nozzle (12), is characterized in that said fluid flow swirler (17) is placed upstream of other end part of the cylindrical chamber, the number of the guiding elements (18) of the swirler (17) is at least three, said guiding elements (18) being uniformly distributed in an azimuth over cross section of the cylindrical chamber, the edges of adjacent guiding elements defining through apertures in a projection onto cross section of the cylindrical chamber, a diaphragm (15) is disposed upstream of said swirler (17) in the course of fluid flow, said diaphragm (15) being equipped with apertures (16) opposed with respect to the through apertures in said swirler (17), with the structure of said atomizer providing an azimuthal movement of said diaphragm (15) relative to an axis of symmetry of the cylindrical chamber.

2. The apparatus of claim 1 wherein the length L of said cylindrical chamber is selected on condition that L < 14d_c, where d_c is diameter of a passage section of a cylindrical portion (23) of said nozzle (12).

3. The apparatus of claim 1 wherein the diameter D of said cylindrical chamber is selected on condition that D > 3d_c, where d_c is diameter of a passage section of said cylindrical portion (23) of said nozzle (12).

4. The apparatus of claim 1 wherein the surface of said guiding elements (18) is made concave in shape.

5. The apparatus of claim 1 wherein the profiled channel of said nozzle (12) is defined by a converging conical portion (22), said cylindrical portion (23) and a diverging conical portion (24), and said portions being arranged in above-mentioned succession.

6. The apparatus of claim 1 wherein the profiled channel of said nozzle (12) is defined by a converging conoid-shaped portion (21), said converging conical portion (22), said cylindrical portion (23) and said diverging conical portion (24), and said portions being arranged in above-mentioned succession.

7. The apparatus of claim 1 wherein the profiled channel of said nozzle is defined by said converging conoid-shaped portion (21), said converging conical portion (22) and said cylindrical portion (23), said portions being arranged in above-mentioned succession.

8. A fluid atomizer (5) comprising a nozzle (12) with a profiled channel, a cylindrical chamber having one end part connected to the inlet of said nozzle (12), and a fluid flow swirler (17) with guiding elements (18), wherein said fluid flow swirler (17) is located upstream of other end part of said cylindrical chamber, the number of the guiding elements (18) of said swirler (17) is at least three, said guiding elements (18) being uniformly distributed in an azimuth over the cross section of said cylindrical chamber, the edges of adjacent guiding elements (18) defining through apertures in a projection onto the cross section of the cylindrical chamber, a diaphragm (15) being located upstream of said swirler (17) in the course of fluid flow, said diaphragm being equipped with apertures (16) arranged opposite the through apertures of said swirler (17), with the structure of said atomizer (5) providing for azimuthal movement of said diaphragm (15) with respect to an axis of symmetry of said cylindrical chamber.

9. The fluid atomizer of claim 8 wherein the length L of said cylindrical chamber is selected on condition that L < 14d_c, where d_c is diameter of a passage section of a cylindrical portion (23) of said nozzle (12).

10. The fluid atomizer of claim 8 wherein the diameter D of said cylindrical chamber is selected on condition that D > 3d_c, where d_c is diameter of a the passage section of said cylindrical portion (23) of said nozzle (12).

1 1. The fluid atomizer of claim 8 wherein the surface of said guiding elements (18) is made concave in shape.

12. The fluid atomizer of claim 8 wherein the profiled channel of said nozzle (12) is defined by a converging conical portion (22), said cylindrical portion (23) and a diverging conical portion (24), said portions being arranged in above-mentioned succession.

13. The fluid atomizer of claim 8 wherein the profiled channel of said nozzle (12) is defined by a converging conoid-shaped portion (21), said converging conical portion (22), said cylindrical portion (23) and said diverging conical portion (24), said portions being arranged in above-mentioned succession.

14. The fluid atomizer of claim 8 wherein the profiled channel of said nozzle (12) is defined by said converging conoid-shaped portion (21), said converging conical portion (22) and said cylindrical portion (23), said portions being arranged in above-mentioned succession.