WO2006028403A1

WO2006028403A1 - Liquid atomizer

Info

Publication number: WO2006028403A1
Application number: PCT/RU2005/000368
Authority: WO
Inventors: Andrey Leonidovich Dushkin; Alexander Vladimirovich Karpyshev; Nikolai Nikolaevich Ryazanczev
Original assignee: Andrey Leonidovich Dushkin; Karpyshev Alexander Vladimirov; Nikolai Nikolaevich Ryazanczev
Priority date: 2004-09-02
Filing date: 2005-07-06
Publication date: 2006-03-16
Also published as: RU2273527C1; EP1824605A1

Abstract

A liquid atomizer comprises a casing (1) provided with at least one supply channel (2) and an outlet slotted passage (3) with an open end part (4). The supply channel (2) is communicating with the slotted passage (3) on the side of its closed end part (5) and is arranged at an angle to a plane of symmetry of the slotted passage. The maximal cross-sectional size of an outlet aperture (9) of the supply channel (2) and a gap between walls (8) of the slotted passage (3) are selected on the determined conditions. The side walls (8) of the slotted passage (3) may be arranged in parallel with each other. The supply channels (2) may comprise closed cavities formed as branches leading from the channel zone where the supply channel (2) is joined to the outlet slotted passage (3). A high-velocity wide-span spatially homogeneous flat jet of finely dispersed liquid droplets is generated at the outlet of the slotted passage (3).

Description

LIQUID ATOMIZER

Field of the Invention

The invention relates to the equipment for creating atomized liquid flows formed as flat gas-and-droplet liquid jets and may be used in fire-suppression systems, sanitary engineering, irrigation units, as well as for deactivation, deodorization and applying of various coatings.

Background of the Invention

A wide range of liquid atomizers adapted for generation of finely dispersed flat gas-and- droplet liquid jets is currently known. For example, Patent FR 2614558 (published 04.11.1988, IPC B05B 1/22) describes a nozzle (an atomizer) with a supply channel and an outlet slotted passage with an open end part provided on the cylindrical surface of the nozzle casing.

The axially symmetric supply channel is communicating with the outlet slotted passage on the side of its open end part. The width of the outlet passage slot ranges between l .ld and 1.2d , where d is a diameter of the supply channel. A plane of symmetry of the slotted passage is extending at an acute angle to an axis of symmetry of the casing and, accordingly, to an axis of symmetry of the supply channel. The side walls of the outlet slotted passage are parallel to each other. A closed end part of the outlet slotted passage is made arcuate.

In the apparatus of the prior art the liquid is atomized by impingement of liquid streams on flat side walls of the slotted passage. The given atomizer allows the liquid to be atomized at low flow rates over a sufficiently vast area of the surface to be sprayed. The disadvantage of the prior art apparatus is a restricted flare angle of an atomized liquid jet: the flare angle does not exceed 140°. The indicated restriction of the sizes of jet generated is due to the arcuate shape of the closed end part of the outlet slotted passage ensuring the concentration of the gas- and-droplet jet in a certain angular sector.

The published patent application JP 2001269603 (issued 02.10.2001, IPC B05B 1/04) discloses a liquid atomizer comprising a casing with two parallel supply channels and an outlet slotted passage with an open end part. The supply channels are communicating with the slotted passage on the side of its closed end part and are facing toward each other in the region of intersection with walls of the slotted passage.

The supply channels are of equal length. The side walls of the slotted passage are extending in parallel to each other. The closed end part of the slotted passage is defined by two surfaces intersecting at a right angle in the area adjacent to the outlet apertures of the supply channels. During operation of the liquid atomizer, a finely dispersed gas-and-droplet jet is created upon collision of the liquid streams preliminarily formed in the supply channels with each other and with the walls of the slotted passage.

The employment of an apparatus of the prior art allows an area of the surface to be sprayed to be increased due to an increased width thereof. Because of this, the application of the given atomizer does not provide generation of a flat finely dispersed gas-and-droplet jet with a minimal angle of divergence in the direction perpendicular to the plane of symmetry of the slotted passage. Such distribution of the gas-and-droplet jet in the space is due to the fact that edges of the outlet aperture of the supply channels are spaced by a minimum possible distance from the edge of the open end part of the slotted passage. It should be noted that during operation of the prior art atomizer, the flare angle of the flat gas-and-droplet jet is ranging between 50° and 120°.

The closest analog to the claimed invention is a liquid atomizer described in the Patent GB 798 645 (published 23.07.1958, IPC B05B 1/04) and having a casing provided with one or two supply channels and an outlet slotted passage with an open end part. The supply channels are communicating with the slotted passage on the side of its closed end part.

The side walls of the slotted passage may be arranged parallel with or at an acute angle to each other. One of the supply channels intersects the side wall of the slotted passage at a right angle and the other supply channel intersects the end wall of the slotted passage.

A transverse through bore may be provided across the atomizer casing for communication with the slotted passage, said bore extending along the end wall thereof. The diameter of the transverse through bore slightly exceeds the width of the slotted passage.

During operation of the atomizer the open end part of the slotted passage is facing toward the surface to be sprayed.

The diameter of the supply channel intersecting the side wall of the slotted passage exceeds the width of the slotted passage by as much as 3-6 times. In a preferred embodiment of the atomizer, the width of the slotted passage is 0.25-0.5 MM.

The prior art apparatus ensures generation of a flat gas-and-droplet jet with a flare angle of about 180° at a liquid stream velocity through the supply channels of about 1 m/s and at a pressure of about 4 MPa. The size of droplets created with the help of the additional transverse through bore near the edges of the gas-and-droplet jet exceeds the size of droplets in the central part of the jet. The non-uniform distribution, with regard to droplet sizes, is provided specially for the purpose of improving the stability of the generated gas-and-droplet jet at a high velocity of an approach air stream. Because of the low velocity of liquid droplets at the outlet of the slotted passage, the restricted flare angle of the flat gas-and-droplet jet and non-uniform distribution of the liquid droplets over the surface to be sprayed, which is due to non-uniformity of the jet with regard to droplet sizes, the prior art atomizer has limited possibilities for effective utilization in various fields of technique, including the employment of the liquid atomizer in fire-suppression systems.

Disclosure of the Invention

The object of the present invention is to create a liquid atomizer providing generation of a high-velocity wide-span spatially homogeneous flat gas-and-droplet jet. Such a jet shall be spatially homogeneous both with regard to droplet density and droplet sizes.

Furthermore, the generated flat gas-and-droplet jet shall have a minimal divergence angle in the direction perpendicular to a plane of symmetry of a slotted passage.

The technical result achieved includes an increase in the efficiency of generating thin sheet-like gas-and-droplet jets with a highly uniform spatial distribution and an increased distance for the maximal extent of covering the surface to be sprayed. Particularly, with the employment of the liquid atomizer in fire-suppression systems, the technical result achieved may exhibit itself in an increased fire-fighting efficiency and effective protection of rooms from smoking up and heat flows at minimal amounts of the liquid consumed. The aforesaid technical results are achieved by employment of a liquid atomizer comprising a casing provided with at least one supply channel and an outlet slotted passage with an open end part. The supply channel is communicating with the slotted passage on the side of its closed end part and is arranged at an angle to a plane of symmetry of the slotted passage and intersects its side wall. According to the present invention, the maximal cross- sectional size d_κ of an outlet aperture of the supply channel and a gap δ between the side walls of the slotted passage in the area of arrangement of the supply channel aperture are selected on the condition that: 0.2d_k < δ < 0.6d_k ; δ > 0.6 mm.

The above combination of essential features of the invention ensures the achievement of a novel technical result due to the high velocity of droplets in the liquid stream, the spatial homogeneity of the gas-and-droplet jet, the flare angle of the jet in the space exceeding 180° and the minimal size of the jet generated in the direction perpendicular to the plane of symmetry of the slotted passage.

The present invention is based on the following prerequisites confirmed by the obtained experimental data. As has been found by the experimental tests, the generation of a wide-span uniform high- velocity flat finely dispersed droplet jet with a minimal divergence angle in the direction perpendicular to the plane of symmetry of the slotted passage is provided only in case predetermined conditions are created for maintaining a predetermined liquid stream velocity mode during transition from the supply channels into the slotted passage of the atomizer.

By recognizing that the transition of flow of a boundary layer of stream from a laminar flow mode into a turbulent steady-state mode in the slotted passage occurs at the same velocity mode as in the supply channel, the following condition should be fulfilled:

where U_∞ is a velocity of the liquid flow running against the plate-shaped side walls of the slotted passage; U_av is an average flow velocity of the liquid in the supply channel.

The second condition on which the present invention is based implies that a film should be formed on the side walls of the slotted passage and, consequently, flowing of the liquid along the slotted passage side walls should be provided in the form of a film flow. To do this requires that during running of the liquid in the slotted passage, the liquid stream is not exposed to essential transverse perturbations in the direction perpendicular to the plane of symmetry of the slot. In this case, the condition for transition of the laminar flow mode to the turbulent flow mode in the boundary layer within the slotted passage should be similar to the respective condition for transition of the flow modes for the cylindrical supply channel. The above assumptions are true only in the case the width of the slotted passage is smaller than the diameter of the supply channel. Otherwise, the liquid stream will not run against the slotted passage surface in the area adjacent to the outlet aperture of the supply channel but will rather issue in the form of a stream from the outlet aperture of the supply channel into the cavity of the slotted passage. Contacting of the liquid stream with the side walls of the passage is possible in the latter case owing to the divergence of the liquid stream or to the directed supplying of the liquid stream onto the side wall of the slotted passage.

It has been found on the basis of the results of experimental tests that a minimal divergence of a generated flat gas-and-droplet jet at the outlet of the slotted passage is achieved with the restriction of the width δ of the passage depending on the maximal cross-sectional size d_κ of the outlet aperture of the supply channel in compliance with the following condition: 0.2d_k < δ < 0.6d_k .

The minimal threshold of the values δ is governed by the influence upon issuing of a gas- and-droplet jet of end effects acting in the supply channel and the slotted passage junction site and by essential reduction in the velocity immediately in the slotted passage, with the result W

5 that reduced pressure zones are created in the slotted passage, which predetermine the spatial non-uniform liquid droplet distribution in the stream. The maximal threshold is due to the action of a transverse perturbation forces causing an increase in the thickness of the gas-and- droplet jet generated. The second condition ensuring the minimized influence of a perturbation force acting perpendicular to the plane of the slot is elimination of the influence of a surface tension force upon predetermined characteristics of a shape of the gas-and-droplet jet.

The influence of the surface tension force is exhibited to a greater extent when the minimal size of the atomizer, which, for the claimed apparatus, is the gap δ between the side walls of the slotted passage, is selected on the following condition: δ « b, where b is a capillary constant determined from the formula: σ b =

; g(p_e -p_g) where: σ is a surface tension coefficient of the liquid, H/m; g is a gravitational acceleration, m/s";

Pi is density of the liquid, kg/m³;

P_g is density of a gaseous fluid into which the liquid is atomized, kg/m³.

For water (a medium to be sprayed) and for air (a surrounding medium) b « 3 mm.

Another condition for the liquid atomizing procedure is the exceeding of the surface tension force over the inertial mass force. The ratio of the above forces for the case when the liquid flows from the channel into the slot gap may be derived using a similarity criteria.

In the supply channel, the Laplasian criterion Lp₅ = d-_κp_eσ I μ² _, where μ is a dynamic viscosity coefficient of the liquid, determines the ratio of the surface tension force to the viscosity force in the channel. For the slot gap, the Galilean criterion Ga_g= p_e gδl μ² determines the ratio of inertial mass force to the viscosity force in the gap.

In a general way, the Lp_s/Ga_s ratio illustrates the ratio of the surface tension force to the inertial mass force at a boundary where the transition of the liquid flow from the supply channel into the slotted passage occurs. With fulfillment of the Lp_s/Ga_g > 1 condition, the surface tension force prevails over the inertial mass force upon issuing of the liquid from the supply channel into the slot gap. The given relationship defines optimal conditions for uniform atomization of the liquid.

It has been found experimentally that the influence upon formation of an atomized liquid jet of the surface tension force, which is also dependent upon the material of the atomizer passage wall, is minimized with optimal conditions for the liquid atomization procedure when the following dependence is fulfilled: δ > l/5b.

Consequently, in the cases when the liquid to be atomized is water and the surrounding gaseous medium is air: δ > 0.6 mm. When the given condition is fulfilled with regard to the slotted passage of the atomizer, the influence of the surface forces upon geometric sizes of the generated gas-and-droplet jet is eliminated regardless of the material from which the walls of the slotted passage are manufactured, for example from steel or fluoroplastic.

When the above condition is not fulfilled, a gas-and-droplet jet generated at the outlet of the slotted passage with the walls made from steel has a small flare angle in the plane of the slotted passage, said jet being concentrated along the central part of the slotted channel. When the walls of the slotted passage are made from flouroplastic, the violation of the above condition will cause the gas-and-droplet jet to be divided into two separate jets. Such jets will issue from the slotted passage at an angle of 180° to each other, with the central part of the slotted passage remaining unfilled.

With an atomizer having more than two supply channels, the maximal cross-sectional size d_κ of the outlet aperture of the supply channel is selected so as to fulfill the above conditions in compliance with the following relationship:

where d^, d^, d_kN are maximal cross-sectional sizes of the apertures of the supply channels, N is the number of supply channels.

In case several supply channels are used, it is advisable that these channels be equal in length. This is necessary for symmetrical distribution of the liquid streams in the slotted passage. It is also advisable that a distance h from the edge of the outlet aperture of the supply channel to the edge of the open part of the slotted passage in the course of issuing of the liquid stream be selected according to the condition that: 3.5d_k < h < 28d_k

The given condition defines the influence of the turbulence extent of the liquid stream running onto a flat surface of the slotted passage. It is known that a turbulence extent of a liquid stream is defined by the values of the critical Reynolds number. With the case under consideration for the liquid stream running onto a plate, the designed values of the Reynolds number Re _κp are within the following range (see. Shlikhting G. The boundary layer theory. M., SCIENCE, 1974., pages 440, 441) : Re _κp= 3.5-10⁵ ÷ 2.8-10⁶. The above condition for the distance h have been obtained on the basis of equality of the velocities of the liquid streams running through the supply channels and running along the slotted passage of the atomizer, with the designed values of the Re_κp number for the minimal and maximal extent of perturbation of the turbulent liquid stream having been also taken into account. In a general way, the critical Reynolds number for the plate is determined from the following expression:

Re ₀.=^ ,

V where: x is a length of the plate; v is kinematic viscosity of the liquid.

With the case under consideration using flat side walls of the slotted passage, a length x of the plate corresponds to the distance h from the edge of the outlet aperture of the supply channel to the edge of the open end part of the slotted passage in the course of issuing of the liquid stream: x =h.

The transition of the laminar flow mode to a turbulent flow mode in the supply channel is determined from the value of the critical Reynolds number Re s_cr - 10⁵ estimated for the cylindrical channel from the following formula:

The following dependence was produced as a result of solving the system of the above equations:

The given essential condition (3.5d_k < h < 28d_k) was obtained by integrating in the resulting dependence of the numerical values Re sc_r with a high and a low stream turbulence extent.

The slotted passage may have various spatial configurations: a flat configuration for the case when the side walls of outlet slotted passage are disposed parallel to each other, or wedge- shaped configuration diverging in the course of issuing of the liquid stream. In the latter case it is desirable that the flat side walls of the slotted passage be arranged at an angle of 1-3°. An inclination angle of an axis of symmetry of the supply channel to the plane of symmetry of the slotted passage may range from 5° to 90°.

In a preferred embodiment of the invention, one supply channel may have a closed cavity formed as a branch leading from the channel zone adjacent to the supply channel and the outlet slotted passage junction site. Such a closed cavity serves as a resonator for creating pressure fluctuations in the supply channels for the purpose of increasing the efficiency of liquid stream dispersion.

Depending on the desired flare angle of the gas-and-droplet jet, the closed end part of the outlet slotted passage may be formed arcuate or it may be defined by two surfaces intersecting in the area of the outlet aperture of the supply channel. Furthermore, the closed end part of the slotted passage may be formed as a flat surface extending in parallel with the outlet edge of the open part of the slotted passage.

In the preferred embodiment of the invention, the atomizer may include at least one movable deflector bridging the side open end part of the slotted passage. The use of the movable deflector allows the spatial distribution of the generated gas-and-droplet jet to be controlled during functioning of the atomizer.

The outlet aperture of the supply channel may be defined by intersection of the supply channel surface with the flat side surface of the slotted passage and with the surface of the closed end part of the slotted passage. In other versions of embodiment, the supply channel surface intersects only with the side wall of the slotted passage.

The supply channel may be equipped with a liquid stream swirl unit arranged upstream of the channel outlet aperture. Such a swirl unit permits formation of a liquid swirl flow at the inlet of the slotted passage for the purpose of increasing the efficiency of splitting the liquid stream into small droplets and the distance of discharging the jet generated. In order to create a spatially homogeneous gas-and-droplet jet symmetrical with respect to an axis of symmetry of the slotted passage, the plane of symmetry of the slotted passage is extending at an angle of from 88° to 92° to the plane of arrangement of the axes of symmetry of the supply channels.

Brief Description of Drawings

The invention is further explained by the examples of concrete embodiment of the liquid atomizer with references to the exemplifying drawings provided in a (2:1) enlargement scale. The exemplifying drawings illustrate the following:

Fig. 1 is a longitudinal cross-section of a liquid atomizer provided with one supply channel;

Fig. 2 is a sectional view in a plane A - A of an atomizer illustrated in Fig 1 ; Fig. 3 is a longitudinal section of an atomizer provided with two supply channels;

Fig. 4 is a cross-sectional view in a plane B-B of an atomizer illustrated in Fig. 3; Fig. 5 is a longitudinal section in a plane C-C of an atomizer illustrated in Fig 3; Fig. 6 is a longitudinal section of an atomizer provided with two supply channels having liquid stream swirl units and with a movable deflector; Fig. 7 is a cross-sectional view in a plane D-D of an atomizer illustrated in Fig. 6;

Fig. 8 is a longitudinal section in a plane E-E of an atomizer illustrated in Fig. 6; Fig. 9 is a longitudinal section of an atomizer provided with two supply channels and a wedge-shaped slotted passage;

Fig. 10 is a cross-sectional view in a plane F-F of an atomizer illustrated in Fig 9; Fig. 11 is a longitudinal section in a plane G-G of an atomizer illustrated in Fig. 9;

Fig. 12 is a longitudinal section of an atomizer provided with two supply channels and a movable deflector and having a flat closed end part of a slotted passage;

Fig. 13 is a cross-sectional view in a plane H-H of an atomizer illustrated in Fig. 12; Fig. 14 is a longitudinal section in a plane I-I of an atomizer illustrated in Fig. 12.

Preferable Example of Embodiment of the Invention

According to the first embodiment of the invention (see Figs 1 and 2), an atomizer comprises a casing 1 with a thread provided on a portion of the external surface of the casing and adapted for connecting the atomizer to a pipeline of a liquid supply system (not shown in the drawing). The casing 1 has a supply channel 2 oriented at an acute angle relative to an axis of symmetry of the casing 1, and an outlet slotted passage 3 provided with an open end part 4 made in the form of an arc of circle.

The open end part 4 is defined by intersection of the cylindrical side surface of the casing 1 with the slotted passage 3. The supply channel 2 is communicating with the slotted passage 3 on the side of its closed end part 5.

An angle CL of inclination of an axis of symmetry 6 of the supply channel 2 to a plane of symmetry 7 of the slotted passage 3 is 90° (within the range of optimal values of from 5° to 90°). Flat side walls 8 of the outlet slotted passage 3 are arranged in parallel with each other (see Fig. 1). In the embodiment of invention under consideration, the closed end part 5 of the slotted passage 3 is formed as a flat surface. An outlet aperture 9 of the supply channel 2 is provided in the side wall 8 of the slotted passage 3. The cross-section of the outlet aperture 9 of the supply channel 2 in the plane of the side wall 8 is made annular. In this case, the maximal cross- sectional size d_κ of the outlet aperture 9 is commensurable with a diameter of the supply channel 2. The diameter of the supply channel is 4.5 mm (Fig. 2).

A gap δ between the side walls 8 of the slotted passage is 2 mm, i.e., within the range of values δ of from 0.9 mm to 2.7 mm, said range being calculated to comply with an essential condition of the claimed invention: 0.2d_k < δ < 0.6d_k ; δ > 0.6mm.

In the example of embodiment under consideration, a distance h from an edge 10 of the outlet aperture 9 of the supply channel 2 to an edge of the open end part 4 of the slotted passage 3 in the course of issuing of the liquid flow is selected to be equal to 20 mm (see Fig. 2). The indicated value is within the range of optimal values of from 16 mm to 126 mm, said range being calculated to comply with the condition that 3.5d_k < Ii < 28d_lc with d_κ=4.5 mm.

According to the second example of embodiment of the invention (see Figs 3 to 5), the liquid atomizer comprises a cylindrical casing 11 provided with two supply channels 12 equal in length and an outlet slotted passage 13 with an open end part 14. An outlet end edge 15 is provided on the open end part 14 of the slotted passage 13 and outlet side edges 16 are provided on the side cylindrical surface of the casing 11 (see Fig. 5).

An inclination angle α of an axis of symmetry 17 of each of the supply channels 12 to a plane of symmetry 18 of the slotted passage 13 is 20°, i.e., it is within the range of optimal values of from 5° to 90°. The plane of symmetry 18 of the slotted passage 13 is arranged at an angle β =90° to the plane within which the axes of symmetry of the supply channels 12 are extending. The given angle is selected to be within the range of optimal values of the angle β: from about 88 ° to about 92°.

The slotted passage 13 is defined by plane-parallel walls 19. The supply channels 12 are communicating with each other and with the slotted passage 13 on the side of its open end part 20. Outlet apertures 21 of the supply channels 12 are defined by intersection of the surfaces of the supply channels 12, the surfaces of the flat side walls 19 and an arcuate surface of the closed end part 20 of the slotted passage 13 (see Fig. 5). In the example of embodiment under consideration, an outlet aperture 21 of each of the supply channels 12 in the plane of the slotted passage has an elliptical section (see Fig. 5). The maximal sectional size of the aperture 21 in the example of embodiment of the atomizer under consideration is 4 mm. The maximal designed sectional size d_κ of the outlet aperture of the two supply channels 12 calculated according to the condition d_k = (d_ki + d^ + ... d_kN)/N is 4 mm. Width S of the side walls 19 is 30 mm.

In the given example of embodiment of the invention, the closed end part 20 of the slotted passage 13 is made arcuate (see Fig. 5). The gap δ between the walls 19 of the slotted passage 13 is 2 mm, i.e., within the range of optimal values δ of from 0.8 mm to 2.4 mm. The indicated range of values δ is calculated with d_k=4 mm in accordance with the condition wherein the value of the gap is selected depending on the maximal cross-sectional size of the outlet aperture of the supply channels 12: 0.2d_k< δ < 0.6d_lc.

A distance h from a lower edge 22 of the outlet aperture 21 of each of the supply channels 12 to the edge 15 of the open end part 14 of the slotted passage 13 is 16 mm (see Fig. 5). The selection of values h is limited to be within the range of optimal values of from 14 mm to 112 mm, said range being calculated according to the condition: 3.5d_k < h < 28d_k (with d_κ=4 mm).

A distance / from an upper edge 23 of the outlet apertures 21 of the supply channels 12 to an apex of a concave surface of the closed end part 20 of the slotted passage 13 is 2 mm (see Fig. 5).

According to the third example of embodiment of the invention (see Figs 6 to 8), a liquid atomizer comprises a cylindrical casing 24 provided with two supply channels 25 and an outlet slotted passage 26 with an open end part 27. An outlet edge 28 of the open end part 27 is defined by intersection of the side surface of the casing 24 with the slotted passage 26. Side edges 29 are extending along the side surface of the casing 24 in parallel with its axis of symmetry. The supply channels 25 are connected with each other in the area where they join to the slotted passage 26 on the side of its closed end part 30 (see Fig. 6).

The slotted passage 26 is defined by plane-parallel walls 31. The supply channels 25 have inlet portions 32 and outlet portions 33. The channels 25 are of equal length up to the point where these channels join with each other near the closed end part 30 of the slotted passage 26. An angle Ot of inclination of an axis of symmetry 34 of the outlet portion 33 of each of the supply channels 25 to a plane of symmetry 35 of the slotted passage 26 is 70° to comply with the range of optimal values of the angle α of from 5 ° to 90°. The plane of symmetry 35 of the slotted passage 26 is arranged at an angle β=90° to the plane in which the axes of symmetry of the supply channels are extending, i.e., within the range of optimal values of the angle β of from 88° to 92° (see Fig. 7).

The outlet apertures of the supply channels 25 are defined by intersection of the surfaces of the outlet portions 33 of the channels 25 by the plane-parallel side walls 31 and by the surface of the closed end part 30 of the slotted passage 26 (see Fig. 6).

The supply channels 25 have closed cavities 36 formed as branches leading from the channel area where it is joined with the outlet slotted passage 26. In order to provide closed cavities 36, the outlet portions 33 of the supply channels 25 on the side of the side surface of the casing 24 are closed by means of inserts 37.

An annular movable deflector 38 is positioned coaxially to the cylindrical casing 24 of the atomizer. The deflector 38 is joined with the side surface of the casing 24 so as to move axially along a side edge 29 of the slotted passage 26. The deflector 38 is movable between the position wherein the side part of the slotted passage 26 is fully open and the position wherein the side surface of the slotted passage 26 is fully closed. Fig. 6 illustrates the deflector 38 in its intermediate position, i.e., between the extreme positions of full opening and full closing the side part of the slotted passage 26.

The supply channels 25 of the liquid atomizer in the example of embodiment under consideration are equipped with liquid swirl units located upstream from the outlet apertures of the supply channels 25. The swirl units are formed as portions of helical paths 39 and 40 provided in the outlet portions 33 of the supply channels 25. The helical paths are oppositely oriented: the helical line of the path 39 is right-handed and that of the path 40 is left-handed (see Fig. 6).

The closed end part 30 of the slotted passage 26 is defined by two symmetrical surfaces 41 and 42 intersecting in the zone adjacent to the outlet apertures of the supply channels 25.

An inclination angle γ of the surfaces 41 and 42 to the plane of symmetry 35 of the slotted passage 26 is 80° . Each of the side walls of the slotted passage 26 has the width of 30 mm (see Fig. 8).

The outlet apertures of the supply channels 25 have an elliptical cross-section in the plane of symmetry of the slotted passage 26 (see Fig. 8). The maximal cross-sectional size d_KN of the outlet apertures of each of the supply channels 25 is 4 mm. The maximal design size d_κ of the outlet aperture of the two supply channels 25 calculated in accordance with the condition: d_k= (d_ki + d^ + ... d_kN)/N is also 4 mm. The size of a gap δ between the side walls 31 of the slotted passage 26, as in the previously described versions of embodiment of the atomizer structure, is selected to be 2 mm according to the range of optimal values δ = 0.8 - 2.4 mm, said range being calculated in accordance with the condition: 0.2d_k < δ < 0.6d_k ; δ > 0.6 mm. A distance h from a lower edge 43 of the outlet aperture of the supply channels 25 to an edge 28 of the open end part 27 of the slotted passage 26 is selected to be 16 mm (see Fig. 7) according to the designed range of optimal values h. A distance / from an upper edge 44 of the outlet aperture of the supply channels 25 to an apex of a convex surface of the closed end part 30 of the slotted passage 26 is 2.5 mm (see Fig. 8). According to the forth example of embodiment of the invention (see Figs 9 to 1 1), a casing 45 of an atomizer is provided with two supply channels 46 and an outlet slotted passage 47 with an open end part 48. In the given example of embodiment of the atomizer structure, the slotted passage 47 is formed as a wedge diverging in the course of issuing of the liquid stream. The open end part 48 of the slotted passage 47, as in other versions of embodiment of the invention, has an outlet edge 49 and parallel side edges 50 defined by intersection of the side surface with the slotted passage 47.

The supply channels 46 are communicating with each other and with the slotted passage 47 in the zone adjacent to a closed end part 51 of the slotted passage 47. Outlet apertures 52 of the supply channels 46 are defined by intersection of the surfaces of the channels 46 with side walls 53 of the slotted passage 47 and with the surface of its closed end part 51 (see Fig. 11).

The flat side walls 53 of the wedge-shaped slotted passage 47 are arranged at an angle φ = 2° (see Fig. 9) with respect to each other. The optimal values of the angle φ are ranging between 1° and 3°.

An inclination angle α of axes of symmetry 54 of the supply channels 46 to a plane of symmetry 55 of the slotted passage 47 is 20°(see Fig. 9). The given value complies with optimal values α ranging between 5 ° and 90°.

The plane of arrangement of the axes of symmetry 54 of the supply channels 46 is inclined toward the plane of symmetry 55 of the slotted passage 47 at an angle β=90° (see Fig. 10), i.e., within the range of optimal values of from 88 ° to 92°. The closed end part 51 of the slotted passage 47 is made arcuate. The outlet apertures 52 of the supply channels 46 in the plane of the slotted passage 47 have an elliptical cross-section. Each of the side walls 53 has width of 30 mm (see Fig. 11). The maximal cross-sectional size d_KN of the outlet aperture of each of the supply channels 46 in the plane of the slotted passage 47 is 4 mm.

The gap δ between the walls 53 of the slotted passage 47 in the zone adjacent to the aperture 52 of the supply channels 46 is selected to be 2 mm, i.e., within the range of optimal values of from 0.8 mm to 2.4 mm (see Fig. 9), with the maximal design size d_κ for the two supply channels calculated according to the dependence dk = (d^ + d_k2 + ... d_kN)/N also being

4 mm.

The distance h from a lower edge 56 of the outlet apertures 52 of the supply channels 46 to the outlet edge 49 of the open end part 48 of the slotted passage 47 is 25 mm (see Fig. 11), i.e., within the design range of from 14 mm to 112 mm according to the condition: 3.5d_k ≤ h ≤ 28d_k.

The distance / from an upper edge 57 of the outlet apertures 52 of the supply channels 46 to a bending point of the concave surface of the closed end part 51 of the slotted passage 47 is 2.5 mm (see Fig. 11). According to the fifth example of embodiment of the invention (see Figs 12 to 14), a liquid atomizer comprises a casing 58 provided with two supply channels 59 and an outlet slotted passage 60 with an open end part 61. An outlet edge 62 of the open end part 61 of the slotted passage 60 is defined by intersection of the end surface of the casing 58 with the slotted passage 60. Side edges 63 are defined by intersection of a cylindrical side surface of the casing 58 with the slotted passage 60.

The supply channels 59 are equal in length and are provided with inlet portions 64 and outlet portions 65. The outlet portions 65 of the channels 59 are communicating with each other and with the slotted passage 60 in the zone adjacent to its closed end part 66.

A distinctive feature of the given example of embodiment of the invention is the shape of closed end part 66 of the slotted passage 60, which is formed as a flat surface extending parallel to the outlet edge 62 of the open end part 61.

Axes of symmetry of the inlet portions 64 are extending in parallel with a plane of symmetry 67 of the slotted passage 60. An inclination angle α of the axes of symmetry 67 of the outlet portions 65 of the supply channels 59 to a plane of symmetry 68 of the slotted passage 60 is 80° (within the range of optimal values of from 5 ° to 90°). Side walls 69 of the slotted passage 60 are parallel to each other. Outlet apertures 70 of the supply channels 59 are defined by intersection of surfaces of the outlet portions 65 of the channels with surfaces of side walls 69 and with the flat surface of the closed end part 66 of the slotted passage 60 (see Fig. 14).

The supply channels 59 have closed cavities 71 formed as branches leading from the outlet portions 65 of the channels 59. In order to create the closed cavities 71, the outlet portions 65 of the supply channels 59 are closed at the side surface of the casing 58 by means of inserts 72.

An annular movable deflector 73 is located coaxially to the cylindrical surface of the casing 58. The deflector 73 is joined with the side surface of the casing 58 so as to move axially along the side edge 63 of the slotted passage 60. The deflector 73 is movable between the position wherein the side part of the slotted passage 60 is fully open and the position wherein the side part of the slotted passage 60 is fully closed. Figs 12 and 14 illustrate the deflector 73 in its intermediate position, i.e., between the extreme positions of opening and closing the side part of the slotted passage 60. A plane of symmetry 68 of the slotted passage 60 is arranged at an angle β=90° to the plane within which the axes of symmetry of the supply channels 59 are extending. The angle β complies with the range of optimal values β of from 88° to 92°.

In the example of embodiment of the invention under consideration, width S of the side walls 69 of the slotted passage 60 is 30 mm. The outlet aperture 70 of each of the supply channels 59 is made elliptical (see Fig. 14). The maximal cross-sectional size d_KN of the outlet aperture 70 of each of the supply channels 59, as in the previous examples of embodiment, is 4 mm. The maximal designed cross-sectional size of the outlet aperture of the supply channels is also 4 mm according to the condition: d_k = (di_d + di^ + ... d_kN)/N.

The value of gap δ between the side walls 69 is selected to be within a range of design values δ (from 0.8 mm to 2.4 mm) and is 2 mm.

The distance h from a lower edge 74 of the outlet aperture 70 of the supply channel 59 to the outlet edge 62 of the open end part 61 of the slotted passage 60 is 27 mm (within the range of optimal values h of from 14 mm to 112 mm). The distance / from an upper edge 75 of the outlet aperture 70 to the flat surface of the closed end part 66 of the slotted passage 60 is 2.5 mm (see Fig. 14).

The operation of the liquid atomizer implemented according to the aforesaid examples of embodiment of the invention (see Figs 1 to 14) and, accordingly, the procedure for generation of an atomized liquid jet are accomplished in the following manner. During operation of the liquid atomizer implemented according to the first example of embodiment of the invention, the working liquid is delivered under pressure of about 0.8 MPa from the main liquid supply line into the supply channel 2 of the atomizer. The liquid pressure in the supply channel 2 may vary within the range of from 0.5 MPa to 2 MPa. The liquid stream formed in the channel 2 is delivered through the outlet aperture 9 of the supply channel 2 into the cavity of the slotted passage 3. Owing to creation of conditions for the film-mode issuing of the liquid, a directed liquid stream is formed in the slotted passage 3 which runs onto the side walls 8 of the slotted passage 3 at a predetermined velocity mode. The liquid stream is spreading over the surface of the side walls 8 in an angular sector defined by the surface of the closed end part 5 of the slotted channel 3.

The film-mode issuing of liquid from the slotted passage 3 is provided through its open end part 4 at a flow velocity of about 40 m/s. The film-mode issuing of liquid through the slotted passage 3 is enabled by maintaining the velocity mode of the liquid stream upon transition from the supply channel 2 through its outlet aperture into the cavity of the slotted passage 3. The conditions required for maintaining the velocity mode are ensured, as indicated above, by fulfilling a predetermined proportion between geometric sizes of the supply channels (dk) and the slotted passage (δ):

0.2d_k < δ < 0.6d_k ; δ > 0.6 mm.

A gas-and-droplet jet is generated as a result of disintegration of the film stream at the section of the slotted passage 3 upon cooperation with the surrounding air. The liquid film begins to disintegrate into small droplets at a distance of several millimeters from the edge of the open end part 4 of the slotted passage 3.

The film disintegration process occurs under the influence of the two main factors. First, breaking down of the film is due to the development therein of separate perforations. The perforations in the liquid film are increasing until a net is formed consisting of thin filaments disintegrating into a plurality of small droplets.

Second, disintegration of the film is due to the formation thereon of fluctuating waves running perpendicular to the course of issuing of the stream, with the amplitude of said waves increasing as they move away from the edge of the open end part 4 of the slotted passage 3. The film is disintegrated by the action of the waves into thin filaments which are further split into droplets.

The above processes result in the formation at the section of the slotted passage 3 of a flat spatially homogeneous gas-and-droplet jet with an average droplet size of about 300 μm. Fulfillment of a predetermined proportion of sizes of the supply channels and the slotted passage allows the gas-and-droplet jet generated to have minimal divergence angle in the direction perpendicular to the plane of symmetry of the slotted passage. A flare angle of the jet in the plane of the slotted passage is 180° and the distance of discharging the jet exceeds 3 m.

The liquid atomizer implemented according to the present invention may be utilized for the generation of high-velocity gas-and-droplet jets to create sheet-like droplet curtains. Such curtains are used for protecting people in the closed spaces from smoke and thermal effects from a fire source.

To this end, in order to protect the passengers in the underground from fire, atomizers are located in the lower part of a tunnel in such a manner that the open end part 4 of the outlet slotted passage 3 is oriented upward.

The sheet-like gas-and-droplet jet is generated upon supplying of a working liquid under pressure of 1.6 MPa into the supply channel 2 of the casing 1. The film-like liquid stream formed in the slotted passage 3 issues through the open end part 4 of the slotted passage 3.

The processes of disintegration of the liquid film and generation of a flat spatially homogeneous gas-and-droplet jet are similar in this case to the above described processes.

While lifting to a height of about 6 M, the atomized jet essentially reaches the upper level of the tunnel and the liquid droplets fall downward by gravity toward the ascending gas-and-droplet jet.

The liquid droplets that have changed the direction of motion due to gravity fall downward at a relatively low velocity to thereby form a liquid sheet (fog). The liquid droplets move at a low velocity while attracting finely dispersed combustion products moving together with a hot air flow. The result is that the gas-and-droplet jet absorbs the combustion products, and a gas flow coming from the side of the burning source is cooled. So, the generated flat gas- and-droplet jet effectively hinders spreading of smoke and heat flows coming from the fire sources to thereby create conditions for localizing thereof.

The use of a reasonably narrow slotted passage in the atomizer, the sizes of which meet essential conditions of the present invention, the influence of the material of the slotted passage walls and the related surface tension forces upon the process of generating a spatially homogeneous flat gas-and-droplet jet is reduced. The experiments performed have shown that the employment of the atomizer with a steel casing having a gap satisfying predetermined conditions resulted in the generation of a gas- and-droplet jet with a low flare angle in the direction perpendicular to the plane of symmetry of the slotted passage. In case an atomizer having a fluoroplastic casing is employed, when the conditions for selecting the sizes of supply channels and a slotted passage are not fulfilled, two streams are formed that issue from the slotted passage in the zone adjacent to its closed end part at an angle of 170-180° to each other, with issuing of the liquid in the central region of the open end part of the slotted passage being essentially nullified.

Reduction of the gap δ to the value below a minimal admissible value of 0.2d_k leads to deflecting the issuing of the gas-and-droplet jet from the initial rectilinear direction in parallel with the axis of symmetry of the slotted passage and forming a jet diverging in the direction perpendicular to the plane of symmetry of the slotted passage. As a result of violation of a predetermined regulation, non-uniformity of the liquid flow rate along the plane of symmetry of the slotted passage is enhanced. The liquid flow rate increases in the direction away from the central part of the side wall of the slotted passage toward its edge. The maximal liquid flow rate is achieved in the zones where the surface of the closed end part of the slotted passage is joined with its side walls. Separate liquid streams are observed to be formed in the indicated zones.

On the other hand, an increase in the gap δ to the value exceeding the maximal admissible value of 0.6d_k results in an essential increase in a divergence angle of the jet in the direction perpendicular to the plane of symmetry of the slotted passage.

With reduction of the distance h from the edge 10 of the outlet aperture 9 of the supply channel 2 to the edge of the open end part 4 of the slotted passage below 3.5dk , the area of the surfaces of the side walls 8 of the slotted passage 3 proves to be insufficient for steady-state liquid issuing and, correspondingly, forming of a flat gas-and-droplet jet.

An increase in the value h above 28d_k does not facilitate formation of a spatially homogeneous gas-and-droplet jet with a flare angle exceeding 180° due to increased kinetic energy losses by friction against the surfaces of slotted passage side walls.

Utilization of liquid atomizers with various inclination angles α of the axis of symmetry 6 of the supply channel 2 to the plane of symmetry 7 of the slotted passage 3 within the range of optimal values of from 5° to 90° permits obtaining of flat finely dispersed jets with flare angles in the plane of the slotted passage within the range of from 150° to 180°. It should be noted that the greater are the inclination angles α of the axis of symmetry of the supply channel 2 to the plane 7 of symmetry of the slotted passage, the greater are the flare angles of the jet generated. The liquid atomizer implemented in accordance with the second example of embodiment of the invention (see Figs 3 to 5) functions in the similar way.

The working liquid is delivered from the main line under pressure of 8 MPa into the supply channels 12 of the casing 11. The streams formed in the supply channels 12 are combined into a single stream in the vicinity of the upper edge 23 of the outlet apertures 21 of the supply channels 12. The liquid stream is further delivered into the cavity of the slotted passage 13 while running onto its side walls 19. In the slotted passage 13 the liquid issues in the film-mode flow. The film-like liquid stream issues through the open end part 14 of the slotted passage 13 at a velocity of about 40 m/s. During disintegration of the liquid film beyond the slotted passage 13, the liquid stream is dispersed to thereby form a finely dispersed gas-and-droplet jet with an average droplet size of about 250 μm and a flare angle of 170°. The distance of discharging the jet generated is at least 3 m.

The arcuate shape of the closed end part 20 of the slotted passage 13 ensures formation of an atomized liquid jet with a steady flare angle, with the value of said angle being defined by a radius of curvature of the surface.

The distance / from the upper edge 23 of the outlet aperture 20 of the supply channels 12 to the apex of the concave surface of the closed end part 20 of the slotted passage 13 is selected on the condition that maximal spatial homogeneity of the generated gas-and-liquid jet be provided. The given condition is determined by experiments and may be expressed in the following form: δ< / < 3δ.

High dispersity of the jet generated is achieved by forming the outlet aperture 21 of the supply channels 12. The aperture 21 is defined by intersection of the surfaces of the supply channels 12, the flat side walls 19 of the slotted passage 13 and the closed end part 20 of the slotted passage 13. It has been found out experimentally that an increase in the forming surfaces intersecting with one another to thereby define the outlet aperture 21 allows an average droplet size to be reduced.

Formation of a flat liquid stream in the direction parallel to the plane of symmetry of the slotted passage is ensured by arranging the plane of symmetry 18 of the slotted passage 13 at an angle β having a value selected within the range of optimal values of from 88° to 92°. In case the above condition is not fulfilled, the film-like liquid stream deviates from the rectilinear issuing direction owing to redistribution of perturbing forces at the outlet of the slotted passage. The above effect is also noted in the cases when the condition of equality in the length of the supply channels is not fulfilled. The generation of a liquid jet by means of a liquid atomizer implemented in accordance with the third example of embodiment of the invention (see Figs 6 to 8) is effectuated in the similar manner. The following differences exist in the functioning of the given version of the atomizer structure. The movable deflector 38 as part of the atomizer allows a flare angle of a flat gas-and- droplet jet to be regulated in a plane of symmetry of the slotted passage 26 before starting of the atomizer or during functioning thereof.

In case it is desirable to produce an atomized liquid jet with a maximal flare angle, the deflector 38 is located in an extreme upper position wherein the side edges 29 of the open end part 27 are fully opened. The working liquid is delivered from the main line under the working pressure into the inlet portions 32 of the supply channels 25 and further into the outlet portions

33.

The liquid streams are swirled in the cavity of the outlet portions 32 of the channels 25 by means of oppositely oriented helical portions of the paths 39 and 40. As a result, swirled streams are formed at the inlet of the slotted passage 26 having angular velocities with oppositely oriented velocity components. The swirled liquid streams are discharged through outlet apertures of the supply channels 25 into the cavity of the slotted passage 26. The swirled streams formed are combined into a single stream near the upper edge 44 of the outlet apertures of the supply channels 26. In the process of supplying the working liquid through the supply channels 25, the cavities 36 whose end parts are closed by means of inserts 37 become blocked by the stream. As a consequence, the liquid does not penetrate into the cavities 36 filled with air. Variations in the static pressure within the liquid stream cause cyclic variations in the pressure within the closed cavities 36. Periodic compression and expansion of air in the cavities 36, in turn, give rise to pressure fluctuations within the liquid flow.

The above processes result in the formation within the slotted passage 26 of a fluctuating liquid stream running onto the side walls 31. The film-like liquid stream then issues through the open end part 27 of the slotted passage at a velocity of about 40 m/s. The processes of breaking down the film-like stream, dispersion and formation of finely dispersed gas-and- droplet jet in the case under consideration are similar to those typical for the above described examples of embodiment of the invention.

The employment of the closed cavities 36 allows the uniformity of the gas-and-droplet jet with regard to droplet sizes to be improved, the droplet sizes to be reduced and the liquid stream dispersion efficiency to be increased. Owing to the above, the gas-and-droplet jet formed downstream from the section of the slotted passage has an average droplet size of about 200 μm.

Also, upon swirling of the liquid streams within the helical paths 39 and 40 in opposite directions, the liquid stream created in the slotted passage 26 acquires additional kinetic energy. As a consequence, an additional increase in the distance of discharging and in a flare angle of the gas-and-droplet jet is ensured. The distance of discharging the jet generated is 4 m and the flare angle is 270°.

An increase in the flare angle is also achieved by making the closed end part 30 of the slotted passage 26 in the form of two symmetrical surfaces 41 and 42 which intersect in the area adjacent to outlet apertures of the supply channels 25.

Functioning of the liquid atomizer implemented according to the forth version of the atomizer structure (see Figs 9 to 11) is provided in the manner similar to that described with regard to the above described examples of embodiment of the invention. The differences in the functioning of the liquid atomizer are as follows. Implementation of the slotted passage 47 in the form of a wedge diverging in the course of issuing of the liquid stream and having side walls 53 arranged at an angle φ = 2° to each other (the angle φ being selected within the range of from 1° to 3°) ensures generation of a flat spatially homogeneous atomized liquid stream having a predetermined thickness (the size in the direction perpendicular to the plane of symmetry 55 of the slotted passage 48). During operation of the liquid atomizer of the given structure version, a spatially homogeneous gas-and-droplet jet is created downstream from the section of the slotted passage 48 with a droplet size of about 250 μm and a flare angle in the plane of symmetry of the slotted passage of 170°. The distance of discharging the gas-and-droplet jet generated is about 3 m.

Functioning of a liquid atomizer implemented according to the fifth version of the atomizer structure (see Figs 12 to 14) is accomplished in the manner similar to that for the above described examples of embodiment of the invention. The differences in the functioning of the given version of embodiment of the invention are as follows.

For the purpose of generating a jet with a predetermined flare angle of the jet generated (about 180°), the closed end part 66 of the slotted passage 60 is made in the form of a flat surface extending in parallel with the outlet edge 62 of the open end part 61 of the channel.

During supplying of the working liquid into the supply channels 59, a finely dispersed gas-and-droplet jet is created downstream from the section of the slotted passage having an average droplet size of about 200 μm and a jet flare angle of 180°. The distance of discharging the jet is about 3 m.

Thus, the above examples of embodiment of the invention confirm the possibility of acquiring a novel technical result including the generation of a finely dispersed high-velocity wide-span gas-and-droplet jet possessing the required extent of spatial homogeneity with a minimal angle of divergence of the jet in the direction perpendicular to the plane of symmetry of the slotted passage.

Industrial Application of the Invention Liquid atomizers implemented in accordance with the present invention may be utilized in various branches of industry, primarily in fire suppressing equipment. Along with it, the invention may be employed in sanitary and agricultural engineering as deactivation and deodorization means and in other branches of industry where the generation of finely dispersed wide-span flat gas-and-droplet jets is required. As one of the examples of implementing the invention, the ability of utilizing a liquid atomizer for creating protective sheet-like curtains should be noted, said sheet-like curtains being used for preventing combustion products from spreading in a closed space.

The above example of embodiment of the invention is preferable though it does not cover any other possible versions of embodiment of the invention without exceeding the scope of the invention which may be implemented by means of the prior art equipment and methods known to those skilled in the art.

Claims

CLAIMS We claim:

1. A liquid atomizer comprising a casing (1) provided with at least one supply channel (2) and an outlet slotted passage (3) with an open end part (4), said supply channel (2) communicating with the slotted passage (3) on the side of its closed end part (5) is arranged at an angle to a plane of symmetry (7) of the slotted passage (3) and is interesting its side wall (8), is characterized in that a maximal cross-sectional size d_κ of an outlet aperture (9) of the supply channel (2) and a value of a gap δ between side walls (8) of the slotted passage (3) in the area adjacent to the aperture (9) of the supply channel (2) are selected on the conditions that: 0.2d_k < δ < 0.6d_k ; δ > 0.6 mm.

2. A liquid atomizer of claim 1, characterized in that with the number of the supply channels (2) equal to or greater than two, a maximal cross-sectional size d_κ of the outlet aperture (9) of the supply channels (2) is selected on the condition that: dk = (did + dia + ... d_k>i)/N, where d_ki, d_k2, d_kN are maximal cross-sectional sizes of the apertures of the supply channels (2), N is a number of the supply channels (2).

3. A liquid atomizer of claim 2, characterized in that the supply channels (2) are equal in length.

4. A liquid atomizer of claim 1, characterized in that a distance h from an edge of the outlet aperture (9) of the supply channel (2) to an edge of the open end part (4) of the slotted passage (3) in the course of issuing of the liquid stream is selected on the condition that:

3.5d_k ≤ h < 28d_k 5. A liquid atomizer of claim 1, characterized in that the side walls (8) of the slotted passage (3) are parallel to each other.

6. A liquid atomizer of claim 1, characterized in that the slotted passage (3) is formed as a wedge diverging in the course of issuing of the liquid stream.

7. A liquid atomizer of claim 6, characterized in that the flat side walls (8) of the slotted passage (3) are arranged at an angle of 1-3°.

8. A liquid atomizer of claim 1, characterized in that an inclination angle of an axis of symmetry of the supply channel (2) to a plane of symmetry of the slotted passage (3) is 5-90°.

9. A liquid atomizer of claim 1, characterized in that at least one supply channel (25) has a closed cavity (36) formed as a branch leading from the channel in the area where the supply channel (25) is joined to a slotted passage (26).

10. A liquid atomizer of claim 1, characterized in that a closed end part (56) of a slotted passage is made arcuate.

11. A liquid atomizer of claim I₅ characterized in that a closed end part (30) of the slotted passage is defined by two surfaces (41 and 42) intersecting in the area adjacent to an outlet aperture of the supply channel (25).

12. A liquid atomizer of claim I₅ characterized in that a closed end part (66) of a slotted passage is made in the form of a flat surface extending in parallel with an outlet edge of an open end part (61) of the slotted passage.

13. A liquid atomizer of claim 1, characterized in that it comprises at least one movable deflector (73) bridging the open side end part of the slotted passage (60).

14. A liquid atomizer of claim I₅ characterized in that an outlet aperture (21) of a supply channel (12) is defined by intersection of a surface of the channel (12), a flat side surface of a slotted passage (13) and a surface of a closed end part (20) of the slotted passage (13).

15. A liquid atomizer of claim 1, characterized in that the supply channel (25) is provided with a liquid stream swirl unit (39 or 40) located upstream of the outlet aperture of the channel (25).

16. A liquid atomizer of claim I₅ characterized in that a plane of symmetry (35) of the slotted passage (26) is arranged at an angle of 88-92° to a plane where axes of symmetry of the supply channels (25) are extending.