LIQUID ATOMIZER

The Field of the invention

The invention relates to gas-and-droplet jet generation means adapted for generation of flat gas-and-droplet jets. The invention may be used in fire-fighting systems, irrigation apparatuses, processing equipment adapted for various purposes such as deactivation and deodorization means, and also for applying various coatings, as well as cooling means.

Background of the invention

It is known from US Patent No 3635407 (published on 18.01.1972, IPC B05B 1/26) a liquid atomizer having a casing comprising two baffle plates adapted for dividing the casing internal cavity lengthwise of the course of flow of the liquid into a pressure chamber and a discharge chamber. The first baffle plate is equipped with two apertures equal in diameter and arranged symmetrically in relation to an axis of symmetry of the pressure chamber. The second baffle plate functions as an end wall of the liquid atomizer casing. The second baffle plate is equipped with a liquid atomizer discharge opening. The pressure chamber is communicating with a liquid supply pipeline.

The liquid atomizer is furnished with a splitter axially aligned with the casing downstream of a plane of the discharge opening. The splitter side surface facing the atomizer discharge opening is made conoid-shaped. The splitter is mounted on a rod extending through the atomizer discharge opening and is secured on the first baffle plate. The cross section of the discharge opening is formed annular.

Liquid is delivered from the supply pipeline into the casing pressure chamber wherein the stream is widened and the liquid pressure is equalized across the chamber section. The liquid is then guided from the pressure chamber through the apertures provided through the first baffle plate into the discharge chamber. In the discharge chamber, the liquid flow velocity gradually increases as the flow-through channel is narrowing toward the atomizer discharge opening.

An atomized liquid jet is formed in the process of flowing of the liquid along a guiding profiled surface of the splitter and subsequent issuing thereof through the atomizer discharge opening.

The employment of a prior art apparatus provides for a uniform spraying of a surface due to a preliminary equalizing of a working fluid pressure across the section of a pressure chamber. Furthermore, the prior art apparatus allows the course of flow of an atomized jet, the

liquid flow velocity and the degree of spray dispersion to be regulated by axially shifting a splitter relative to a discharge opening.

However, the distance of discharging a generated gas-and-droplet jet is restricted owing to the liquid kinetic energy losses occurring as a result of striking a high-speed stream against the profiled surface of the splitter.

The US Patent No4813610 (published on 21.03.1989, IPC B05B 1/26) describes a liquid atomizer (injector) having a casing comprising two chambers: a pressure chamber and a discharge chamber. Said chambers are separated from one another by means of a baffle plate provided with two apertures equal in diameter and arranged symmetrically relative to an axis of symmetry of the pressure chamber. A atomizer discharge opening provided through an end part of the casing is axially aligned with an axis of symmetry of the pressure chamber. The cross section of the atomizer discharge opening is formed circular in shape. The side surface of the discharge chamber is equipped with a cylindrical inlet portion and a conical outlet portion continuously narrowing in the course of flow of the liquid. The conical portion of the chamber functions as a deflecting surface in the atomizer construction.

The liquid streams issuing from the pressure chamber via the apertures provided through the baffle plate flow along the cylindrical portion wall in parallel with the axis of symmetry of the chamber. As a result of cooperation of parallel liquid streams with the conical surface of the chamber outlet portion the streams are deflected toward one another. A finely dispersed atomized liquid jet is generated as a result of impingement of the streams downstream from a plane of the atomizer discharge opening. Depending on the selected sizes of the conical deflecting surface, two atomized liquid jets are generated or a single conical jet with an oval-shaped section is generated.

It should be noted that owing to a substantial extension of the discharge chamber in the process of flowing of the liquid streams up to an atomized jet formation region, the kinetic energy of the stream is wasted in friction against the air filling the chamber.

The closest prior art of the claimed invention is a liquid atomizer described in US Patent No2626836 (published on 27.01.1953, IPC B05B 1/26). The prior art atomizer has a casing comprising two baffle plates. The baffle plates divide the casing internal cavity in the course of flow of the liquid into a pressure chamber and a discharge chamber.

The first baffle plate is equipped with two apertures equal in diameter and arranged symmetrically relative to an axis of symmetry of the pressure chamber. The second baffle plate functioning as an end wall of the atomizer casing is equipped with a discharge opening of the atomizer, said opening being arranged symmetrically relative to the axis of symmetry of

the pressure chamber. The atomizer is designed so as to allow the end wall of the atomizer to be shifted relative to the first baffle plate.

The liquid atomizer casing consists of two detachable parts joined through a threaded connection. The discharge chamber of the atomizer is made cylindrical in shape. An additional baffling member with an inclined guiding surface may be mounted downstream from the atomizer discharge opening. The plane of the baffling member is arranged at an acute angle to the plane of the atomizer discharge opening.

Generation of an atomized liquid jet by means of the prior art atomizer is enabled due to cooperation of the liquid streams produced in the apertures of the first baffle plate with the internal surface of the end wall of the atomizer casing and the edge of the discharge opening.

The finely dispersed gas-and-droplet jet generated issues through the atomizer discharge opening.

The disadvantage inherent in the design of the prior art apparatus is connected with essential kinetic energy losses occurring as a result of braking the liquid stream upon collision thereof with the surface of the baffling member. Upon collision of the liquid streams with the end wall of the atomizer casing, backflow streams are produced which flow toward the streams issuing from the apertures provided through the first baffle plate.

Disclosure of the invention

It is an object of the present invention to create a liquid atomizer allowing high-speed, flat, wide-spread gas-and-droplet jets to be generated. The jets generated should be characterized by a high spatial homogeneity, an increased distance of discharging working fluid droplets and minimal wastes of kinetic energy.

The technical result achieved involves an increased efficiency in generating of high- distance wide-spread jets. In particular, when the liquid atomizer is employed as a fire-fighting means (as part of fire-fighting equipment) the technical result may exhibit itself in an increased efficiency in extinguishing of high-temperature fire sites. The given effect is due to highly uniform intensive spraying of a high-temperature fire site of vast area, provided that the equipment and personnel may be placed at safe distance from there. In this instance, effective cooling of the fire site surface is enabled with minimal power supply and working fluid consumption. Also, an intensive and homogeneous spraying of liquid over the entire fire site surface area allows oxygen access to a high-temperature zone of the fire site to be cut off.

The technical result is reached with the utilization of a liquid atomizer having a casing comprising two baffle plates dividing the internal cavity of the casing along the course of flow of the liquid into a pressure chamber and a discharge chamber. The first baffle plate is

equipped with two apertures equal in diameter and arranged symmetrically relative to an axis of symmetry of the pressure chamber. The second baffle plate is adapted for serving as an end wall of the liquid atomizer casing and is equipped with a atomizer discharge opening axially aligned with the discharge chamber.

5 According to the present invention, the discharge opening of the liquid atomizer is sized so that a projection of the atomizer discharge opening edge onto the surface of the first baffle plate divides the section of each of the two apertures provided through the first baffle plate into two segments. An area Ss of the segment arranged within the projection of the discharge opening edge should comply with the condition: 0.3 < S _s /S < 0.6, where S is a cross-sectional l o area of the aperture provided through the first baffle plate. Moreover, the sidewall of the atomizer discharge chamber is formed converging in the course of flow of the liquid.

A combination of the aforesaid essential features of the invention allows the technical result to be achieved owing to the generation of a flat fan-shaped atomized liquid jet with an increased kinetic energy of droplets. A spray cone angle of the jet generated in a plane

15 perpendicular to the line extending through the centers of the apertures provided through the first baffle plate is within the range of from 90° to 120°.

Generation of such a jet is enabled owing to the cooperation downstream from the plane of the discharge opening of two arcuate atomized jets produced on the edge of the discharge opening. The arcuate sheet-like flows are produced due to spreading of the liquid over the side 0 surface of the discharge chamber. Spreading of the liquid is, in turn, enabled by a predetermined relative arrangement of the apertures provided through the first baffle plate and the edge of the atomizer discharge opening. The given relative arrangement of the atomizer design components is characterized by a cross-sectional area ratio of segments of each of the apertures. The aperture segments are separated by a projection of the edge of the atomizer 5 discharge opening onto the surface of the first baffle plate.

The subsequent formation of a single gas-and-droplet jet is stipulated by impingement of two symmetrical arcuate atomized streams in a spatial region downstream from the cut of the atomizer discharge opening. Generation of a wide-spread, fan-shaped gas-and-droplet jet is, likewise, facilitated due to creation in the spatial region defined between the two arcuate 0 atomized jets of a reduced static pressure zone. Creation of such a zone promotes approaching and subsequent impingement of two symmetrical atomized jets.

The atomized gas-and-droplet jets are generated within the discharge chamber of the atomizer casing as a result of cooperation of two streams formed on issuing of the liquid through the two apertures provided through the first baffle plate. The experiments have shown

that the achievement of a desirable result is provided in case the parameters of the jets comply with the following conditions:

-linear velocities of the streams should not essentially differ in their values; -liquid flow rates for each of the streams should not substantially differ in their values; -velocity vectors of the streams should be directed parallel to an axis of symmetry of the atomizer discharge chamber;

-jets generated should partly cross the edge of the atomizer discharge opening. With the side surface of the discharge chamber made continuously converging in the course of flow of the liquid, a part of streams flowing in the vicinity of the side wall of the discharge chamber are caused to deviate from the initial direction, in parallel with the axis of symmetry of the discharge chamber, toward the axis of symmetry of the discharge chamber.

Generation of a gas-and-droplet jet having a velocity vector directed in parallel with an axis of symmetry of the discharge chamber is reached by selecting the sizes of the atomizer discharge opening and also the relative arrangement of the apertures provided through the first baffle plate and the discharge opening of the atomizer.

The given condition is characterized in that the projection of the edge of the atomizer discharge opening onto the surface of the first baffle plate should divide the cross section of each of the two apertures provided through the first baffle plate into two segments.

The desirable ratio of the liquid velocity and flow rate values is provided when the area Ss of the aperture segment arranged within the projection of edge of the discharge opening complies with the following condition: 0.3<S _s /S<06.

For the purpose of providing a stabilized flow of streams lengthwise of the side surface of the discharge chamber, the side surface thereof may be made conical or conoid-shaped.

In a preferred version of embodiment of the invention, the cross-section of the atomizer discharge opening is formed circular in shape. In this instance, the projection of edge of the atomizer discharge opening onto the surface of the first baffle plate intersects the axes of symmetry of the apertures provided through the first baffle plate.

The cross section of the atomizer discharge opening may be also formed elliptical. An inclination angle of a side surface generatrix of the discharge chamber relative to the axis of symmetry of the pressure chamber is preferably within the range of from 15° to 50°. With the indicated inclination angles of the side surface generatrix of the discharge chamber, the maximum homogeneous droplet distribution across the section of the wide-spread gas-and- droplet jet is observed.

In the preferred version of embodiment of the invention, a maximal diameter D _max of the cross section of the discharge chamber is from D _CH to (Dc _H -d), where DC _H is the diameter of the pressure chamber, d is the diameter of the apertures provided through the first baffle plate. A distance h from the plane of the apertures provided through the first baffle plate to the plane of the atomizer discharge opening is preferably selected from the following condition: 0.5d ≤ h < 1.5d.

With the given optimal sizes of the atomizer discharge chamber, a maximum uniform spreading of the liquid stream over the side surface of the discharge chamber is enabled and, consequently, a homogeneous gas-and-droplet jet is generated with a homogeneous liquid droplet distribution.

In order to provide for stable formation of the reduced static pressure zone in the space between the sheet-like atomized jets, it is recommended that the distance S between the centers of the apertures provided through the first baffle plate be selected from the condition: d < S < 4d. For adjusting the parameters of the generated gas-and-droplet jet by changing the volume of the atomizer discharge chamber, the first baffle plate may be positioned in the atomizer casing so as to be shifted relative to the end wall of the atomizer casing in the course of flow of the liquid stream.

Brief description of the drawings The invention is further explained by the examples of a concrete embodiment of the liquid atomizer with references to the accompanying exemplifying drawings provided in the 1 :1 scale.

The exemplifying drawings illustrate the following:

Fig. 1 is a longitudinal section of a liquid atomizer with a conical side surface of a discharge chamber;

Fig. 2 is a bottom view of the atomizer of Fig. 1;

Fig. 3 is a longitudinal section of the liquid atomizer with a conoid-shaped side surface of the discharge chamber;

Fig. 4 is a bottom view of the atomizer of Fig. 3. Preferable example of embodiment of the invention

According to the first example of embodiment of the invention illustrated in Figs 1 and 2, a liquid atomizer has a casing 1 comprising two baffle plates: a first baffle plate 2 and a second baffle plate 3, said baffle plates dividing the internal cavity of the atomizer casing lengthwise of the course of flow of the liquid into a pressure chamber 4 and a discharge

chamber 5. The side surface of the discharge chamber 5 is continuously converging in the course of flow of the liquid and defined by a conical surface. In the example of embodiment of the invention under c.onsideration, an angle α of inclination of a side conical surface generatrix of the discharge chamber 5 to an axis of symmetry of the pressure chamber 4 constitutes 45° (within the range of values of the angle α of from 15° to 50°).

The first baffle plate 2 is equipped with two apertures 6 of equal diameter. The apertures 6 are arranged in symmetry with respect to an axis of symmetry of the pressure chamber 4. The diameter d of each of the apertures 6 in the example of embodiment of the invention under consideration is 13 mm. The second baffle plate 3 serving as an end wall of the atomizer casing 1 is equipped with a discharge opening 7 of the atomizer. The discharge opening 7 is axially aligned with the axis of symmetry of the pressure chamber 4. The cross section of the discharge opening 7 is formed circular in shape. In the example of embodiment of the invention under consideration the diameter Do of the discharge opening 7 constitutes 32 mm. It should be noted that an elliptical cross section of the atomizer discharge opening may be provided in other versions of embodiment of the invention. The larger axis of ellipse may extend in parallel with the line connecting the centers of the apertures 6 provided through the first baffle plate 2 as well as perpendicular thereto.

A projection of the edge of the atomizer discharge opening 7 onto the surface of the first baffle plate 2 intersects the centers of the apertures 6 provided through the first baffle plate 2 (see Fig. T). The sizes of the atomizer discharge opening 7 are selected with the provision that the projection of the edge of the discharge opening 7 onto the surface of the first baffle plate 2 divides the cross-sectional area of each of the two apertures 6 provided through the first baffle plate 2 into two segments 8 and 9, the segment 8 being disposed within the projection of the edge of the discharge opening 7 and the segment 9 being disposed beyond the projection of the edge of the discharge opening 7 and closed with the second baffle plate 3.

In the version of embodiment of the invention under consideration, the ratio of an area Ss of the segment 8 to a cross-sectional area S of the aperture 6 constitutes 0.33 (within an allowable range of values of from 0.3 to 0.6). The maximal diameter D _ma χ of the cross section of the discharge chamber 5 of the atomizer casing 1 in the example of embodiment of the invention under consideration is 54 mm (within the range of values D _max of from 58 mm to 45 mm, said range being calculated in accordance with the range of values: from D _C H to (D _CH -d) with DCH ⁼ 58 mm).

A distance h from a plane of the apertures 6 provided through the first baffle plate 2 to a plane of the atomizer discharge opening 7 constitutes 12 mm (within the range of values of from 6.5 mm to 19.5 mm, said range being calculated to comply with the condition: 0.5d < h < 1.5d). The distance S between the centers of the apertures 6 provided through the first baffle plate 2 constitutes 32 mm (within the range of values of from 13 mm to 52 mm, said range being calculated to comply with the condition: d < S < 4d).

According to a second example of embodiment of the invention illustrated in Figs 3 and 4, a liquid atomizer has a casing 10 comprising two baffle plates 11 and 12 dividing the internal cavity of the casing 10 lengthwise of the course of flow of the liquid into a pressure chamber 13 and a discharge chamber 14. The first baffle plate 11 is positioned for shifting relative to an end wall of the atomizer casing. Shifting of the baffle plate 12 is enabled by rotation thereof with the help of a threaded connection of a channel of the casing 10 and the baffle plate 11 (see Fig. 3). The side surface of the discharge chamber 14 is formed continuously converging in the course of flow of the liquid and is defined by a conoid-shaped surface.

The first baffle plate 11 is equipped with two apertures 15 equal in diameter. The apertures 15 are arranged symmetrically to an axis of symmetry of the pressure chamber 13. The diameter d of each of the apertures 15 constitutes 13 mm. The second baffle plate 12 serving as the end wall of the atomizer casing 10 is equipped with a discharge opening 16 of the atomizer. The discharge opening 16 is axially aligned with the axis of symmetry of the pressure chamber 13. The cross section of the discharge opening

16 is made circular in shape. The diameter Do of the discharge opening 16 constitutes 34 mm.

The axes of symmetry of the apertures 15 provided through the first baffle plate 11 (see Fig. 4) are offset relative to the projection of the edge of the atomizer discharge opening 16 onto the surface of the first baffle plate 11. The atomizer discharge opening 16 is sized so that the projection of the edge of the discharge opening 16 on the surface of the first baffle plate 11 divides the cross-sectional area of each of the two apertures 15 provided through the first baffle plate 11 into two segments 17 and 18 (see Fig 4). The segment 17 is positioned within the projection of the edge of the discharge opening 16. The segment 18 is positioned beyond the edge of the discharge opening 16 and is closed with the second baffle plate 12. In the version of embodiment of the invention under consideration, the ratio of the area Ss of the segment 17 to the cross-sectional area S of the aperture 15 constitutes 0.36 (within the range of allowable values of from 0.3 to 0.6).

The maximal diameter D _max of cross section of the discharge chamber 14 of the atomizer casing 10 in the example of embodiment of the invention under consideration constitutes 48 mm (within the range of values D _max of from 58 mm to 45 mm, said values being calculated in accordance with the range of from DQH to (DcH-d) with DCH ⁼ 58 mm). The distance h from the plane of the apertures 15 provided through the first baffle plate

11 to the plane of the atomizer discharge opening 16 is 18 mm (within the range of values of from 6.5 mm to 18.5 mm, said range being calculated to comply with the following condition: 0.5d ≤ h < 1.5d).

The liquid atomizer implemented according to the first example of embodiment of the invention illustrated in Figs 1 and 2 operates in the following manner.

A working liquid is delivered from a supply pipeline under a pressure of 1.2 MPa into the pressure chamber 4 of the casing 1. The working liquid is forced out from the pressure chamber 4 through two apertures 6 provided through the first baffle plate 2 of the casing 1 into the discharge chamber 5. The liquid streams produced in the apertures 6 are guided onto the conical side surface of the discharge chamber 5 to spread over the chamber surface and generate two arcuate liquid streams. Issued from the apertures 6, the streams are of similar shape and have equal velocities at a parallel direction of the velocity vectors.

As a result of cooperation between the two parts of the liquid stream, one of the parts issuing from the side surface of the discharge chamber 5 and the other part issuing without deviation within the space between the first baffle plate 2 and the plane of the discharge opening 7, two fan-shaped atomized liquid jets are generated. The relationship between the cooperating parts of each of the liquid streams is conditioned by selecting the areas of segments of the apertures 6 separated by the projection of the edge of the atomizer discharge opening onto the surface of the first baffle plate 2. The given condition is expressed as: 0.3 < S _s /S < 0.6, where S is the cross-sectional area of the aperture 6 provided through the first baffle plate 2, and Ss is the area of segment of the aperture 6 positioned within the projection of the edge of the atomizer discharge opening.

In case the above condition is fulfilled, two arcuate (crescent) wide-spread jets of atomized liquid are generated at the outlet of the atomizer discharge opening 7, said jets approaching each other in the space due to the creation of a reduced static pressure zone between two symmetrical sheet-like jets having equal velocities and flow rates.

An excessive pressure acting from the environmental space upon the two sheet-like jets, with a reduced static pressure zone created between the jets, results in an approaching of the atomized jets to one another. Drawing of the atomized jets within the space toward the axis of

symmetry of the apertures 6 causes air to be ejected from the environment into the reduced static pressure zone, followed by collapsing of the sheet-like jets.

As the two arcuate atomized jets approach one another, the liquid is intensively mixed with the air to thereby generate a two-phase finely dispersed gas-and-droplet jet flat in shape. The spray cone angle in the plane of symmetry of the apertures 6 is about 120°. The spray cone angle in a perpendicular direction is about 6°. The distance of discharging the generated gas-and-droplet jet was at least 15 m at the total liquid flow rate through the two apertures 6 of 10 1/s. An average droplet size in the jet was about 200 micron.

The experiments made have shown that with the Ss/S ratio reduced to less than 0.3, no spatially homogeneous wide-spread jet is generated. The given effect is a consequence of a violation of the effective ratio of volumetric flow rates of the parts of liquid streams issued from the apertures 6 in the discharge chamber, which is due to a predominance of the part (volumetric flow rate) of the liquid stream issuing from the conical surface of the discharge chamber 5 over the other part of the liquid stream flowing around the edge of the liquid atomizer discharge opening 7. In this instance, the arcuate liquid streams approach one another in the immediate vicinity of the end wall of the liquid atomizer casing.

With an increase in the Ss/S ratio above 0.6, the volumetric flow rate of the liquid stream parts issuing from the conical surface of the discharge chamber 5 is essentially less than the volumetric flow rate of the liquid stream parts flowing around the edge of discharge opening 7 of the liquid atomizer. In this instance the generated arcuate sheet-like streams may intersect each other at a substantial distance from the end wall of the atomizer casing. As a result, the streams will be atomized in the surrounding space before the convergence region thereof without creating a reduced static pressure zone between the two symmetrical atomized jets. Also, in case the above essential condition is not complied with, two independent gas-and- droplet jets may be generated which have no single convergence region wherein a single finely dispersed gas-and-droplet liquid jet should be produced.

With a reduction in an inclination angle of the side conical surface generatrix of the discharge chamber to the axis of symmetry of the pressure chamber 4 to less than 15°, a probability is increased to generate a single liquid jet of a circular section downstream from the discharge opening 7 of the atomizer casing without creation of sheet-like jets (at predetermined liquid flow rate and pressure values in the pressure chamber 4).

When the discharge chamber 5 of the casing 1 has a maximal diameter D _ma χ exceeding the diameter of the pressure chamber D _C H, additional kinetic energy losses of the liquid stream occur at the outlet ends of the apertures 6. The given losses are due to the occurrence of a

vortex effect in the regions disposed in the vicinity of the zone where the side surface of the discharge chamber 5 is joined to the first baffle plate 2.

When the discharge chamber of the casing has a maximal diameter D _max below (Dc _H -d), the sidewall of the discharge chamber 5 may partly overlap the sections of the apertures 6. The result is that additional kinetic energy losses of the liquid stream also occur owing to an increase in the hydraulic resistance upon issuing of the liquid from the apertures 6.

An increase in the distance h from the plane of the apertures provided through the first baffle plate 2 to the plane of the discharge opening 7 to the value exceeding 1.5d results in an expansion and/or offset of the liquid streams issuing from the apertures 6 within the cavity of the discharge chamber 5. As a consequence, a vortex effect occurs near the sidewall of the discharge chamber 5 with the result that the liquid stream kinetic energy losses increase. The indicated phenomena may lead to the creation of individual liquid streams behind the plane of discharge opening, said liquid streams failing to generate a single atomized flat gas-and- dropletjet. Reduction in the volume of the discharge chamber 5, when the distances h are less than

0.5D, the mixing efficiency of the sheet-like streams is substantially decreased behind the end wall of the liquid atomizer casing 1 because the stream mixing region is offset toward the atomizer discharge opening 7.

The distance S between the centers of the apertures 6 is an important parameter defining the characteristics of the generated gas-and-droplet jet along with other geometric and hydrodynamic parameters of an apparatus.

When the distance S is reduced to a value less than d, hydrodynamic cooperation of the liquid streams in the cavity of the discharge chamber 5 and, as a consequence, a partial confluence of the liquid streams before said streams flow past the discharge opening 7 are likely to occur. So ₅ an early hydrodynamic cooperation between the liquid streams is likely to prevent formation of the two individual sheet-like jets at the outlet of the liquid atomizer discharge opening 7.

It should be also pointed out that an increase in the distance S between the apertures 6 by more than 4d may lead to the generation of two individual sheet-like jets which do not cooperate with each other in the space due to an increased distance between the jets. In the latter case the probability of creating a closed zone with a reduced static pressure between the two symmetrical sheet-like jets is eliminated.

Functioning of the liquid atomizer implemented according to the second example of embodiment of the invention illustrated in Figs 3 and 4 is provided in a manner similar to that

of the aforesaid first example of embodiment of the invention complemented with the following additions.

Utilization in the apparatus of the discharge chamber 18 with a conoid-shaped side surface and implementing in the design of the atomizer of the first baffle plate 11 movable relative an end wall of the atomizer casing 10 enables a continuous changing of characteristics of the generated gas-and-droplet jet depending on the volume of the discharge chamber 14 and, correspondingly, on the distance h (see Fig. 3).

Parts of liquid streams issuing from the apertures 15 cooperate with the conoid-shaped side surface and flow from this surface in the form of two symmetrical thin sheet-like jets. With the use of a more continuous transition (as compared to the conical surface) between the sections of the discharge chamber 14 converging in the course of flow of the liquid, hydraulic losses of the liquid streams are decreased and formation of a thin liquid sheet at the outlet of the discharge opening 16 is arisen.

Characteristics of the generated gas-and-droplet jet are controlled by preliminarily moving the baffle plate 12 for a predetermined distance h relative to the end wall of the atomizer casing 10. In the example of embodiment of the invention under consideration the baffle plate 11 is shifted by rotating it with the use of the threaded connection of the channel of the casing 10 with the baffle plate 11.

Industrial application of the invention The invention may be employed as a fire-fighting means for extinguishing large and intensive fire sites, for example, reservoirs containing petroleum products.

The invention may have widespread application as a liquid protecting curtain generator for generating the curtains adapted to protect equipment and personnel from heat fluxes and toxic gases resulting from burning petroleum products. Finely dispersed gas-and-droplet curtains generated by means of the atomizer are characterized by high efficiency in absorbing of combustion products and provide for a reliable thermal protection.

The above examples of embodiment of the invention are preferable, however these examples do not cover any other possible versions of embodiment of the invention which are based on the claims and may be implemented through the employment of means and processes known to those skilled in the given art.