EP1827610A1

EP1827610A1 - Method and sprinkler

Info

Publication number: EP1827610A1
Application number: EP05747212A
Authority: EP
Inventors: Andrey Leonidovich Dushkin; Alexander Vladimirovich Karpyshev; Nikolai Nikolaevich Ryazanczev
Original assignee: Dushkin Andrey Leonidovich; Ryazanczev Nikolai Nikolaevich
Current assignee: Velzen Holdings Ltd
Priority date: 2004-05-11
Filing date: 2005-05-05
Publication date: 2007-09-05
Also published as: RU2258551C1; WO2005107880A1

Abstract

A sprinkler comprises a housing (1) including a cylindrical axial liquid supply channel (2). A liquid stream is divided into two streams by means of a partition wall (3) mounted in the axial channel (2) and symmetrical streams are generated in two flow passages (4). The cross-section of each of the two flow passages (4) in the region close to their outlet openings is configured as a segment of a circle. Frame arms (12) of an attachment fitting for attachment of a deflector (10) of the sprinkler are positioned in a plane of symmetry of the partition wall (3). The liquid streams formed in the flow passages (4) run around the frame arms. The generation of a finely dispersed gas-and-droplet flow is performed with high kinetic energy and uniform spatial distribution of liquid droplets.

Description

METHOD AND SPRINKLER Field of the Invention The invention relates to the liquid atomizing processes and technical means designed for atomization of liquids, such as sprinklers. In particular, the invention may be employed as part of automatic fire-fighting systems for suppressing fires in the rooms with a great number of possible fire sites, such as the rooms in hospitals, libraries, museums, office buildings, warehouses, garages, etc. Description of the Prior Art Various methods of generating an atomized liquid stream are currently known. For example, Patent DE 10010881 (IPC A62C 37/00, published 13.09.2001) describes a method of creating an atomized liquid stream, including the supplying of a liquid under pressure into an axial channel of a liquid atomizer. The liquid stream is divided into two streams by means of a partition wall mounted in the axial channel of the atomizer. The liquid streams symmetrical with respect to a plane of symmetry of the partition wall are formed in flow passages. The tangential supplying of the liquid into the flow passages promotes swirling of the liquid streams in the flow passages in the opposite directions. The liquid streams generated in the flow passages of a chamber disposed at the outlets of the flow passages are mixed to create a turbulent liquid stream. The resulting turbulent liquid stream generated in the chamber is atomized through an outlet opening of the sprinkler channel. The method and the apparatus of the prior art allow atomized liquid streams of a conical shape with a wide range of cone angles to be generated and droplet sizes to be changed. Parameters of gas-and-droplet jets are regulated at a constant pressure of the liquid supplied into the atomizer by changing the outlet opening section. The liquid stream is further turbulized through the use of a profiled baffle located opposite the outlet opening. It should be pointed out that the apparatus of the prior art is free from a thermally responsive unit providing automatic initiation of an atomizer when a predetermined surrounding temperature is reached. The liquid is supplied into the atomizer channel upon opening of a common distributing valve mounted in a main pipeline. In automatic fire-suppressing systems, sprinklers with independent valves are used for liquid atomization, said valves being furnished with thermally responsive unit. Patent US 4800961 (IPC A62C 37/10, published 31.01.1989) discloses a structure of a sprinkler comprising a housing with a cylindrical axial liquid supply channel. An outlet of the axial channel is communicating with four flow passages. A thermally responsive unit is secured in the sprinkler housing by means of an attachment fitting. A deflector is connected to a valve, which closes an inlet opening of the cylindrical axial liquid supply channel. The valve, in conjunction with the deflector, is maintained in an initial position by means of the thermally responsive unit configured as a horizontally positioned bulb. The outlet openings of the flow passages are uniformly distributed around the circumference on an end surface of the sprinkler housing. The axes of symmetry of the flow passages are arranged at an angle to an axis of symmetry of the axial liquid supply channel. A vortex generating chamber is disposed centrally of the sprinkler housing. The employment of a sprinlder of the prior art provides generation of an atomized jet with large liquid droplets to increase the fire-suppressing efficiency and decrease the consumption of liquid. However, because the liquid is atomized toward structural components of the attachment fitting, shielding effects are produced in the process of distribution of an atomized liquid jet. The above effects enhance non-uniform distribution of the liquid droplet jet. A sprinkler and a method of creating an atomized liquid jet are known from Patent EP 0701842 (IPC A62C 37/08, published 20.03.1996). The sprinlder comprises a housing with a cylindrical axial channel, a thermally responsive unit including a valve, and a thermally responsive unit attachment fitting including frame arms. As a predetermined surrounding temperature is reached and the thermally responsive unit of the sprinlder is opened, the liquid is supplied under pressure into the axial channel of the sprinkler. According to an invention of the prior art, the liquid stream is divided into two coaxial streams by means of an annular dividing partition wall mounted in the axial channel of the sprinlder. An outside vortex liquid stream is generated in helical flow passages provided on an outer surface of the partition wall. A central axial liquid stream is generated in an internal axial channel of the partition wall. The resulting streams are delivered into a turbulizing chamber disposed in an axial channel upstream of an outlet opening of the sprinkler. The given method and apparatus allow finely dispersed atomized liquid jets to be generated, said jets having droplet sizes maximum optimal for fire suppression and providing prompt and efficient suppression of a fire site. Yet, the structure of the sprinlder of the prior art does not provide the generation of spatially homogeneous atomized liquid jets. The engagement of the atomized liquid stream with components of the thermally responsive unit attachment fitting results in the occurrence of shielding effects enhancing an increased non-homogeneity in the distribution of the atomized liquid. A portion of the liquid stream flowing from the axial channel opening changes its direction upon contacting with the frame arms of the thermally responsive unit attachment fitting. The regions with a low sprinkling intensity are created in the zones shielded by the frame arms of the attachment fitting, while the regions with an increased sprinkling intensity are created at the boundary of the engagement of the divided streams in a free space. Hence, the uniform suppression of a vast area fire site may not be provided. The closest analog to the claimed method is a method of creating an atomized liquid jet described in Patent US 6073700 (IPC A62C39/00, published 13.06.2000). The actuation of a heat sensitive component of a thermally responsive unit at a predetermined surrounding temperature causes a liquid supply valve to be opened for supplying of liquid into a cylindrical axial channel of a sprinkler. Accordingly, a liquid stream deflector mounted on the same rod as the valve is displaced to its lower operating position. The liquid is delivered under a predetermined pressure into the sprinlder axial channel wherein it is divided into two individual streams by means of a partition wall mounted in the sprinkler axial channel. Liquid streams symmetrical with respect to a plane of symmetry of the partition wall are formed in curved flow passages. The liquid streams thus formed are supplied to an outlet opening of a converging axial channel of the sprinlder to be atomized in the surrounding space owing to the engagement of the streams with the deflector. This results in the generation of a finely dispersed atomized liquid jet. It should be noted that an essential component of the sprinlder structure is an attachment fitting for the deflector and for the thermally responsive unit, including frame arms fixed on the sprinkler housing. Therefore, upon atomizing of the liquid in the spatial region where the attachment fitting frame arms are located, the liquid streams partly intersect with the sprinkler structural components. As a result, the zones with different atomizing intensity and, accordingly, with different intensity of sprinkling of a surface to be protected are created. The closest analog to the claimed apparatus is a sprinlder described in the aforesaid Patent US 6073700. The sprinlder of the prior art comprises a housing with a cylindrical axial liquid supply channel, wherein a partition wall is mounted to divide the axial channel into two curved flow passages symmetrical with respect to a plane of symmetry of the partition wall. A thermally responsive unit and a liquid stream deflector are mounted by means of an attachment fitting in the lower part of the sprinlder. The thermally responsive unit is composed of two heat sensitive mechanisms. The first mechanism includes a component connected with a valve and fabricated from a shape memory alloy. A heat sensitive component is located in the lower part of the housing and connected to a liquid supply valve. The second heat sensitive mechanism of the thermally responsive unit is located opposite an outlet opening of the axial channel and is adapted for maintaining the partition wall in its upper position. The second heat sensitive mechanism comprises plates retained by a component fabricated from a readily fusible alloy. Upon occurrence of a fire, the heat sensitive component fabricated from a shape memory alloy is heated to a shape memory restoring temperature. The heat sensitive component stretches in a vertical direction to maintain the valve in its closed position. Further increase in the temperature of air surrounding the sprinlder leads to melting of the component fabricated from a readily fusible alloy. As a result, supporting plates are separated from the sprinkler to thereby move the deflector to its lower operating position. At the same time, the liquid supply valve is opened for supplying the liquid into the cylindrical axial channel of the sprinlder. On the whole, the operation of the sprinkler and the generation of an atomized liquid jet are provided in accordance with the above-mentioned method for the generation of an atomized liquid jet disclosed in Patent US 6073700. It should be noted that an inherent characteristic of the apparatus as well as of the method is a restriction associated with non- uniform atomizing of liquid above the surface under protection owing to the intersection of the liquid streams with the attachment fitting components. Disclosure of the Invention The invention to be patented is targeted at solving a technical task aimed at elimination of the problem associated with the influence of structural components upon a spatial distribution of liquid droplets in a generated atomized liquid jet. The technical result achieved includes the generation of a finely dispersed gas-and- droplet jet with high kinetic energy of droplets and uniform spatial distribution of liquid droplets, which, in its turn, is of essential significance for effective suppression of fire sites. The above technical result is provided by implementing a method of creating an atomized liquid jet and a sprinlder, including the supplying of a liquid under pressure into an axial channel of the sprinlder as a surrounding temperature reaches a predetermined value and a thermally responsive unit of the sprinlder is opened. The process of implementing the method further includes the dividing of the liquid stream into two streams by means of a partition wall mounted in the axial channel of the sprinlder, and forming in flow passages of the liquid streams symmetrical with respect to a plane of symmetry of a partition wall. The liquid streams generated are atomized through the engagement thereof with a deflector secured on a sprinlder housing by means of an attachment fitting for the deflector and for the thermally responsive unit of the sprinkler. The attachment fitting includes frame arms. According to the present invention, the liquid streams are created in the flow passages to run around the frame arms of the attachment fitting for the deflector and for the thermally responsive unit. The frame arms are positioned in a plane of symmetry of the partition wall mounted in the axial channel. With such an arrangement of the frame arms, water streams are created at the outlet of the axial channel of the sprinlder to run around the frame arms of the attachment fitting for the deflector and for the thermally responsive unit. The aforesaid relative arrangement of the frame arms of the attachment fitting and the outlets of the flow passages reduces losses in kinetic energy of the stream commonly occurring upon intersection of the liquid streams with obstacles, in the particular case, with the frame arms of the attachment fitting. In order to provide a mode most optimal for running of the liquid streams around the frame arms and, accordingly, for improving the uniformity of distribution of the liquid droplets in an atomized liquid jet, conditions are created for generating the liquid streams in the flow passages having a cross-section configured as a segment of a circle in the region close to the outlet openings. The liquid streams formed by means of the flow passages have central zones within which the liquid flows in parallel with a plane of symmetry of the partition wall. Such a flowing promotes the creation of a uniform liquid film and the effective deflection of the liquid stream as it engages with the deflector. In order to produce a uniform finely dispersed gas-and-droplet jet with a high kinetic energy of the droplets, the liquid streams are formed in the flow passages having a length L selected on the condition that: 4D<L<10D, where D is a maximal diameter of a circle inscribed in an outlet section of the flow passages. A length L of the flow passages is selected on the condition that stable flowing of liquid is provided. The length L of the flow passages greater than 10D leads to an increased losses in kinetic energy of the liquid owing to the friction of streams against the flow passage surfaces. The length L of the flow passages smaller than 4D leads to possible radial deviations of the liquid stream from the direction ensuring a maximal uniform spatial distribution of the liquid to be atomized. In order to increase the velocity of droplets and the uniformity of the spatial distribution of the droplets in the atomized jet, the generation of the liquid streams is provided in the flow passages converging in the course of flow of the liquid. In order to prevent the flow passages from obstruction with solid contaminants, the liquid stream flowing through the axial passages of the sprinlder is subjected to filtering before being supplied through said flow passages. The liquid streams generated are preferably atomized by means of the deflector provided with a flat continuous central portion, which is restricted within the geometric boundary of a projection of the cylindrical axial channel. Furthermore, the edges of the deflector may be made perforated and may be configured as a conical surface diverging in the course of flow of the liquid. The employment of the above embodiment of the deflector for atomization of the liquid allows a sprinkling area to be increased at a predetermined uniformity, dispersity and intensity of the gas-and-droplet jet. The above technical result is also attained with the use of a sprinlder comprising a housing including a cylindrical axial liquid supply channel, wherein a partition wall is mounted to divide the axial channel into two flow passages symmetrical with respect to a plane of symmetry of the partition wall, a thermally responsive unit including a valve, a liquid stream deflector, and an attachment fitting for the thermally responsive unit and for the deflector including frame arms. According to the present invention, the frame arms of the attachment fitting for the thermally responsive unit and for the deflector are positioned in a plane of symmetry of the partition wall in the axial channel. The cross-section of each of the two flow passages in the region close to their outlet openings is configured as a segment of a circle. It is practical to select the length L of the flow passages on the condition that: 4D < L < 10D, where D is a maximal diameter of a circle inscribed in an outlet section of the flow passages. The implementation of the given condition provides a stable flowing of the liquid through the flow passages with minimal friction losses in kinetic energy. In order to increase the liquid stream velocity, the flow passages may be made converging in the course of flow of the liquid. To provide a converging shape of the flow passages it is advantageous to use a partition wall diverging in the course of flow of the liquid. An optimal liquid stream velocity through the flow passages sufficient for the maximum efficient atomizing of the liquid stream is achieved by providing a partition wall diverging in the course of flow of the liquid at a gradient of 3-25%. In this case, a finely dispersed gas-and- droplet jet with a high kinetic energy of droplets is generated. With the partition wall gradient less than 3%, no substantial increase in the liquid stream velocity is noted at the outlet of the flow passages. With the partition wall gradient greater than 25%, the losses in kinetic energy of the liquid stream flowing through the flow passages are increased. The partition wall may be mounted in a centering sleeve fixed in the cylindrical axial channel. In this case an accurate positioning of the dividing partition wall is achieved to thereby enable the maximum uniform distribution of the liquid stream in the flow passages relative to a plane of symmetry of the partition wall. In a preferred embodiment of the sprinkler, the width of the frame arms adjoining the point of attachment thereof to the housing shall not exceed the width of the partition wall in the vicinity of the outlet openings of the flow passages. The given structural embodiment allows the losses in kinetic energy of the liquid stream to be decreased to a greater extent and the uniformity of the liquid droplet distribution in the atomized jet to be increased. This results in elimination of a probability of changing the course of flow of the liquid streams as the latter run around the surfaces of the frame arms of the attachment fitting for the thermally responsive unit and for the deflector. A filter with a maximal diameter of apertures equal to or less than 0.8D may be mounted in the cylindrical axial channel of the sprinkler upstream of an entry into the flow passages. The employment of the filter in the sprinlder structure prevents the flow passages from obstruction to thereby enhance the reliability in operation of the sprinkler. In order to increase the sprinkling area, the liquid stream deflector may be provided with a flat continuous central portion positioned within the geometric boundary of a projection of the cylindrical axial channel. With regard to this embodiment of the sprinlder, it is desirable that the diameter of the central portion of the deflector exceed the diameter of the axial cham el by no more than two times. The given limitation is due to a possible decrease in the intensity of sprinkling in the central zone of the area to be sprinkled immediately under the sprinlder with a significant increase in the diameter of the central portion of the deflector. In the preferred embodiment of the sprinlder, the edges of the liquid stream deflector are made perforated and are shaped as a conical surface diverging in the course of flow of the liquid. An inclination angle of the conical surface generatrix to a plane perpendicular to an axis of symmetry of the axial channel is selected in the range of from about 10° to about 30°. The given version of embodiment of the sprinlder structure ensures an increase in the uniformity of distributing a finely dispersed gas-and-droplet jet on large sprinkling areas. The inclination angle greater than 30° results in separation of the liquid stream from the deflector surface and in an increase in the sprinkling intensity at the central zone of the area under sprinkling process in comparison with the peripheral zones. The inclination angle of the conical surface less than 10° results in an axial component of the liquid stream velocity decreasing up to a zero value and in a reduced sprinkling intensity at the central zone. Brief Description of Drawings The invention is further illustrated by a concrete example of implementing the invention including an example of embodiment of a sprinlder operating in accordance with a claimed method of generating an atomized liquid jet. The example of implementation is explained with the appended drawings depicting the following: Fig 1 is a longitudinal sectional view of a sprinlder in a plane of symmetry of a partition wall; Fig 2 is a longitudinal sectional view of a sprinlder illustrated in Fig. 1 in plane A- A; Fig. 3 is a cross sectional view of a sprinkler illustrated in Fig. 1 in plane B-B (the sprinkler is shown in an enlarged scale after opening of a thermally responsive unit and a valve). Preferred Embodiment of the Invention The sprinkler comprises a housing 1 provided with a thread on its outer surface for joining the sprinlder to a liquid distributing pipeline (not shown in the drawing). The housing 1 includes a cylindrical axial liquid supply channel 2 wherein a partition wall 3 is mounted. The partition wall 3 is adapted for dividing the axial channel 2 into two flow passages 4 symmetrical with respect to a plane of symmetry of the partition wall and is fixed in a centering sleeve 5 located inside the axial channel 2. In the version of the embodiment of the invention under consideration, the partition wall 3 is made diverging in the course of flow of the liquid with a gradient of 10% selected in compliance with the range of optimal gradient values of from 3% to 25%. The flow passages 4 defined by the surfaces of the partition wall 3 and of the centering sleeve 5 are made converging in the course of flow of the liquid to conform to the shape of the partition wall 3. The cross-section of each of the two flow passages 4 in the region of their outlet openings is configured as a segment of a circle. Fig. 3 illustrates a circle inscribed in an outlet section of the flow passages 4 and having a maximal diameter D. In the version of the embodiment of the invention under consideration the length L of the flow passages 4 is 6D to comply with the condition of selecting an optimal length of the flow passages 4: 4D<L≤10D. A filter 6 located in the axial channel 2 of the housing upstream of an entry into the flow passages 4 is configured as a cylindrical perforated insert, with a diameter of apertures 7 of the insert making 0.6D to comply with the condition of selecting a maximal size of the filter apertures according to the claims of the invention: not greater than 0.8D. A valve 8 provided with a stopper and fabricated from a polymeric material is adapted for closing an outlet opening of the axial channel 2. The valve 8 is secured in its initial position by means of a thermally responsive unit, a heat sensitive component of which is formed as a glass bulb 9. The glass bulb 9 is filled with a liquid having a volumetric expansion coefficient sufficient for destroying the glass bulb owing to the expansion of liquid as the surrounding temperature reaches a predetermined temperature level. The thermally responsive unit with the glass bulb 9 and the liquid stream deflector 10 are attached to the housing 1 of the sprinkler by means of an attachment fitting for the thermally responsive unit and for the deflector. The attachment fitting comprises a holder 11 for attachment of the deflector 10 and for retaining the glass bulb 9 in its initial position, frame arms 12 for joining the holder 11 with the housing 1, and an adjusting screw 13 for retaining the glass bulb 9 in its initial vertical position. The adjusting screw 13 is located in the axial opening of the holder 11. The frame arms 12 of the attachment fitting for the thermally responsive unit and for the liquid stream deflector are arranged in a plane of symmetry of the partition wall 3 of the axial channel 2 (see Figs 1 and 3). The width L_FA of the frame arms in the region of attachment thereof to the housing 1 does not exceed the width Lpw of the partition wall in the plane of outlet sections of the flow passages 4 (see Fig.3). The liquid stream deflector 10 is provided with a flat continuous central portion 14. The central portion 14 is positioned within the geometric boundary of a projection of the axial channel 2. In an example of embodiment of the sprinkler under consideration, a diameter of the central portion 14 D_CP=1.5D_CH. where D_CH is a diameter of the axial channel 2 of the sprinkler. The diameter Dcp exceeds the diameter D_CH by no more than two times in compliance with the condition of selecting the optimal values of Dcp and D_CH- The edges 15 of the liquid stream deflector 10, lying beyond the geometric boundary of a projection of the axial channel 2 are made perforated and are configured as a conical surface diverging in the course of flow of the liquid. An inclination angle α of a generatrix of the conical surface to a plane perpendicular to the axis of symmetry of the axial channel is 20°, i.e., it is within the range of optimal values α of from about 10° to about 30° (see Fig. 2). The operation of the sprinkler and the implementation of a method for generation of an atomized liquid jet are provided in the following manner. The sprinlder is joined through a threaded connector to a distributing pipeline (not shown in the drawing), whereupon the pipeline and the axial channel 2 of the sprinlder are filled with a working liquid at a pressure ranging from about 0.4 MPa to about 1 MPa. In the example under consideration the pressure is 0.6 MPa. When a surrounding temperature reaches a predetermined value, which in the example of embodiment under consideration is 68°C, the glass bulb 9 is destroyed under the pressure of the expanded liquid. Once the glass bulb is destroyed, the valve 8 with a stopper is removed from the outlet opening of the axial channel 2 under the action of pressure of the working liquid filling the axial channel 2. After opening of the valve closing the axial channel 2 of the sprinkler, the liquid flows under the pressure of 0.6 MPa through the filter 6, which catches solid particles hindering the normal operation of the sprinkler. The liquid stream is divided in the axial cham el 2 into two streams by means of the partition wall 3. An accurate positioning of the partition wall 3 in the axial channel 2 is enabled by means of the centering sleeve 5. The liquid is then delivered into the flow passages 4 defined by the side surfaces of the partition wall 3 and the internal surface of the centering sleeve 5. Two liquid streams generated in the converging flow passages 2 are characterized by the availability of central zones with maximal density. In the central zones, the liquid flows in parallel with a plane of symmetry of the partition wall 3 wherein the frame arms 12 of the thermally responsive unit attachment fitting are located. Therefore, in the process of flowing of the divided liquid streams through the converging flow passages 4, the directed liquid streams flowing at a predetermined velocity are generated. The liquid streams generated in the flow passages 4 and flowing symmetrically with respect to the plane of symmetry of the partition wall 3 are further directed to the outlet openings of the flow passages 4 and then to the outlet opening of the axial channel 2, through which the generated liquid streams are atomized. The liquid is atomized in a spatial region limited by the frame arms 12 of the attachment fitting for the deflector 10 and for the thermally responsive unit. In the process of atomizing the generated liquid streams by means of the deflector 10 provided with a flat continuous central portion 14, an atomized liquid stream is formed and discharged in a radial-axial direction. On splitting of such a stream, a uniform finely dispersed gas-and-droplet jet is created on the perforated portion of edges 15 of the deflector 10. The liquid streams reach the surface of the central portion 14 of the deflector 10 to run around the frame arms 12 of the attachment fitting for the thermally responsive unit and for the deflector. On the surface of the central portion 14 of the deflector 10 the liquid streams, which had been preliminarily divided in the flow passages 4, are combined to form an atomized stream in the form of a film flowing in a radial-axial direction toward the edges 15 of the deflector 10. As such a stream flows onto the perforated conical surface of the edges 15 of the deflector 10, the thickness of the film reduces and the liquid is split into fine droplets as it slips-off from the edges of the conical surface and flows through the depressions (perforations) provided on the edges 15 of the deflector 10. As a result of the given processes, the atomized liquid jets are generated with a radial-axial direction of flow characterized by the availability of an axial component of the flow velocity. The experiments performed have shown that the application of the method for generating an atomized liquid jet and of the sprinkler for implementation of the method for generation of an atomized liquid jet enables an increase in the area of sprinkling by means of a finely dispersed gas-and-droplet jet with a uniform spatial distribution of droplets and kinetic energy of droplets sufficient for effective extinguishing of a fire site. In the process of liquid atomization, the water was split into fine droplets having size equal to or less than 140 micron and a uniform gas-and-droplet jet was generated on an area of 9 9 14 m at a sprinkling intensity of 0.045 kg/m s at a root-mean-square deviation of the intensity over the said area equal to or less than 20%. It should be pointed out that the employment of a sprinkler described in the Patent EP 0701182 provides generation at the same pressure of a liquid jet with a size of droplets of 9 9

210 micron over an area of 10 m at a sprinkling intensity of 0.05 kg/m s and at a root-mean- square deviation of the intensity over the said area equal to or greater than 36%. The employment of a wide-known AM25-type sprinlder of the Grinell Company provides generation at the same pressure of a gas-and-droplet jet on an area of 6 m² with an average droplet diameter of 380 micron at the sprinkling intensity of 0.075 kg/m²s and a root- mean-square deviation of the intensity over the said area of 42 %. So, in comparison with the prior art, the implementation of the claimed method and sprinlder ensures the generation of a finely dispersed gas-and-droplet jet with high kinetic energy of droplets and uniform spatial distribution of liquid droplets over the surface to be sprinkled. Industrial Application of the Invention With the aforesaid advantages, the invention may be used in automatic fire-suppression systems fitted in the rooms furnished with valuable equipment and interior, in particular, in the rooms of hospitals, libraries, museums, office buildings, warehouses, garages, etc. The above example of utilizing the inventions is preferable, however it does not exhaust any other possible versions of embodiment of the invention based on the claims of the invention, which may be implemented with the help of technical means and methods lαiown by those skilled in the art.

Claims

CLAIMS We claim:

1. A method for generation of an atomized liquid jet, including the supplying of a liquid under pressure into an axial channel (2) of a sprinkler as the surrounding temperature reaches a predetermined temperature and a thermally responsive unit of the sprinkler opens; dividing a liquid stream into two streams by means of a partition wall 3 mounted in the axial channel 2 of the sprinkler; forming liquid streams in the flow passages 4, said streams running symmetrically with respect to an axis of symmetry of the partition wall (3) and atomizing the generated liquid streams through the engagement thereof with a deflector (10) secured on a housing (1) of the sprinkler by means of an attachment fitting for the deflector (10) and the thermally responsive unit, the said attachment fitting comprising frame arms (12), is characterized in that liquid streams are formed in the flow passages (4) to run around the frame arms (12) of the attachment fitting for the deflector (10) and for the thermally responsive unit, with the frame arms (12) being positioned in a plane of symmetry of the partition wall (3) of the axial channel (2).

2. The method of claim 1 is characterized in that the liquid streams are formed in the flow passages (4), with a cross-section of each of the flow passages in the region close to their outlet openings being configured as a segment of a circle.

3. The method of claim 1 is characterized in that the liquid streams are formed in the flow passages (4), a length L of which is selected on the condition that: 4D < L < 10D, where D is a maximal diameter of a circle inscribed into an outlet section of the flow passages (4).

4. The method of claim 1 is characterized in that the liquid streams are formed in the flow passages (4) converging in the course of flow of the liquid.

5. The method of claim 1 is characterized in that the dividing of the liquid stream in the axial channel (2) of the sprinkler is provided in the flow passages (4) converging in the course of flow of the liquid.

6. The method of claim 1 is characterized in that before supplying of the liquid into the flow passages (4), the liquid stream flowing through the axial channel (2) of the sprinkler is subjected to filtering.

7. The method of claim 1 is characterized in that the generated liquid streams are atomized by means of the deflector (10) provided with a flat continuous central portion (14), which is positioned within a geometric boundary of a projection of the cylindrical axial channel (2).

8. The method of claim 1 is characterized in that the generated liquid streams are atomized by means of the deflector (10), the edges (15) of which protruding beyond a geometric boundary of a projection of the cylindrical axial channel (2) are made perforated and are configured as a conical surface diverging in the course of flow of the liquid.

9. A sprinlder comprising a housing (1) with a cylindrical axial liquid supply channel (2), wherein a partition wall (3) is mounted to divide the axial channel (2) into two flow passages (4) symmetrical with respect to a plane of symmetry of the partition wall (3), a thermally responsive unit provided with a valve (8), a liquid stream deflector (10) and an attachment fitting for attachment of the thermally responsive unit and the deflector (10), including frame arms (12), is characterized in that the frame arms (12) of the attachment fitting for the thermally responsive unit and for the deflector (10) are positioned in a plane of symmetry of the partition wall (3) of the axial channel (2), with a cross-section of each of the two flow passages (4) in the region close to their outlet openings being configured as a segment of a circle.

10. The sprinlder of claim 9 is characterized in that a length L of the flow passages

(4) is selected on the condition that: 4D < L < 10D, where D is a maximal diameter of a circle inscribed in an outlet section of the flow passages (4).

11. The sprinlder of claim 9 is characterized in that the flow passages (4) are made converging in the course of flow of the liquid.

12. The sprinlder of claim 9 is characterized in that the partition wall (3) is made diverging in the course of flow of the liquid with a gradient of 3-25%.

13. The sprinkler of claim 9 is characterized in that the partition wall (3) is mounted in a centering sleeve (5) fixed in the cylindrical axial channel (2).

14. The sprinlder of claim 9 is characterized in that a width of the frame arms (12) in the region of attachment thereof to the housing (1) does not exceed a width of the partition wall (3) in the region close to the outlet openings of the flow passages.

15. The sprinkler of claim 9 is characterized in that a filter (6) is positioned in the cylindrical axial channel (2) upstream of the entry into the flow passages (4), the said filter having apertures (7) with a maximal diameter equal to or less than 0.8D.

16. The sprinkler of claim 9 is characterized in that the liquid stream deflector (10) is provided with a flat continuous central portion (14) positioned within the geometric boundary of a projection of the cylindrical axial channel (2), with a diameter of the central portion (14) of the deflector (10) exceeding that of the axial channel (2) by no more than two times.

17. The sprinlder of claim 9 is characterized in that edges 15 of the liquid stream deflector (10) lying beyond the geometric boundary of a projection of the cylindrical axial channel (2) are made perforated and are configured as a conical surface diverging in the course of flow of the liquid, with an inclination angle of the conical surface generatrix to a plane perpendicular to an axis of symmetry of the axial channel ranging from about 10° to about 30°.