JP4863693B2 - Two-fluid injection nozzle and oil burner - Google Patents

Description

  The present invention relates to a two-fluid jet nozzle capable of jetting a fluid at a high speed and having straightness, and an oil burner using the jet nozzle.

  In general, a jet burner is configured to send fuel and combustion air into a combustion cylinder and inject combustion gas burned in the combustion cylinder from a Laval nozzle at a high speed. The Laval nozzle is designed so that the injection speed of the combustion gas exceeds the speed of sound, and the structure is a mere medium-thin nozzle, and no particular contrivance is found in the nozzle shape. This type of jet burner is differentiated by providing features in the combustion chamber cooling structure and combustion air supply means.

  As for this jet burner, for example, a first combustion chamber that supplies high-pressure air from the periphery of the combustion chamber on the central axis of the burner body to generate a swirl combustion flow, and further, preheated high-pressure air is supplied to provide a swirl flow. And a second combustion chamber that forms a vortex high-temperature combustion part is arranged, and is ejected from the second combustion chamber through a constricted throttle-like shock wave conversion part (Laval nozzle) that raises the combustion gas to a sound speed or higher. Patent Document 1 discloses a structure in which the periphery of the second combustion chamber has a triple-pipe structure, and high-pressure air is circulated therein to serve as cooling means for preheating and maintaining the combustion chamber. Yes.

  In addition to this, the combustion air is preheated and supplied around the combustion chamber, and a double pipe structure is provided to cool and protect the combustion chamber, and combustion gas is ejected from the combustion chamber through a Laval nozzle at high speed. The jet burner is known from Patent Document 2 or Patent Document 3.

  On the other hand, in addition to the jet burner, in order to atomize and spray water, water is supplied to the surroundings ejected from the air ejection nozzle and stirred and mixed in the mixing chamber, and from the injection port provided at the tip of the mixing chamber Patent Document 4 discloses a two-fluid injection nozzle configured to eject a mixed fluid of water and air to spray fine particles.

Japanese Patent No. 3634325 JP 11-82940 A JP 09-21508 A Japanese Utility Model Publication No. 5-63658

  However, the conventional jet burner, as is known from the above-mentioned Patent Documents 1, 2, or 3, jets the combustion gas generated in the combustion cylinder at a high speed, and is more fluid (combustion gas) than combustion heat. It is used for cutting and crushing rocks at high speed. In the jet burner disclosed in Patent Document 1, vortex flow is caused in combustion gas by the air supplied to the combustion chamber, and the vortex is jetted from the jet outlet at a speed higher than the speed of sound. According to such a method, the combustion gas ejected from the injection port is rapidly diffused by the swirling flow, and even if it has a function of generating a shock wave, it is stalled and it is difficult to expect straightness. . Further, since high temperature combustion is performed in the combustion cylinder, it is necessary to protect the combustion cylinder, and it is used as a preheating path for the supply air, but there is a problem that a cost increase is unavoidable due to the multiple pipe structure.

  On the other hand, an ordinary two-fluid injection nozzle, as known from Patent Document 4, pursues atomization of liquid, and since the two fluids after spraying stall at the same time as injection, linear high-speed injection and fine particles It is difficult to achieve both. Therefore, it cannot be used in a state where the fluid is sprayed from the ejection position to a far position.

  In order to solve the above-described problems, the present invention has a structure in which air is attracted around the fluid to be ejected so that the ejected fluid is straightly moved when the two-fluid ejection is performed using the Laval nozzle structure. An object of the present invention is to provide a two-fluid spray nozzle configured to include an oil burner that uses the spray nozzle.

In order to achieve the above object, the two-fluid injection nozzle according to the first invention comprises:
Inside the nozzle head attached to the end of the double pipe is a guide body provided with a first fluid flow hole communicating with the inner pipe of the double pipe and a second fluid flow hole communicating with the outer pipe. In the mixing chamber formed between the peripheral surface of the guide body and the inner wall of the nozzle head, the two fluids are mixed and flow into the suction part of the Laval nozzle shape, and the Laval nozzle shape diffuser outlet front position In addition, a plurality of vertically long air suction holes are disposed around the ejection flow path of the mixed fluid along the axis.

In the first aspect of the present invention, the guide body has a second half in the axial direction as a fitting portion in the nozzle head, a front half is smaller in outer diameter than the fitting portion, and a hook-like protrusion is formed at the front end. Are provided with a recess communicating with the inside of the inner tube, and a plurality of flow holes communicating with the inside of the outer tube are formed radially by dividing a plurality of small-diameter flow holes from the recess toward the outer periphery of the first half. It is structured to be provided parallel to the axis, and is closely fixed to the tip of the double pipe by the nozzle head at the fitting portion, and from both the flow holes between the inner wall surface of the nozzle head and the outer peripheral surface of the front half. It is preferable that a mixing chamber for two fluids to be ejected is formed, and an annular ejection flow path for the mixed fluid is formed by the flange-like protruding portion and the inner surface of the suction portion having the Laval nozzle shape ( second invention). ).

In the guide body, the inner tube communication flow hole and the outer tube communication flow hole may be provided at the same circumferential angle ( third invention).

In the first invention, the injection flow rate may be set by changing the throat diameter of the Laval nozzle as well as changing the diameter and / or the number of flow holes provided in the guide body ( fourth invention).

Further, the oil burner of the fifth invention is
A guide body having a circulation hole for fuel oil supplied through the inner pipe of the double pipe and a distribution hole for compressed air supplied through the outer pipe is disposed inside the nozzle head attached to the end of the double pipe. The mixing chamber formed between the peripheral surface of the guide body and the inner wall of the nozzle head communicates with the suction portion of the Laval nozzle shape, and is vertically elongated along the axis at the Laval nozzle shape diffuser outlet front position. A plurality of air suction holes are arranged, and air is sucked from the air suction holes around the mixture of fuel oil and air ejected from the diffuser, so that a highly straight flame is generated by the mixture to be injected. It is the structure obtained.

In the fifth aspect of the invention, the guide body may be configured such that the flow rate of two fluids can be set by changing the hole diameter and / or the number of arrangement of both flow holes provided ( sixth aspect ). In the fifth aspect of the present invention, it is preferable that the combustion amount and the flame amount are set by changing the throat diameter of the Laval nozzle as well as changing the diameter and / or the number of flow holes provided in the guide body ( seventh). invention).

According to the present invention (the first invention) , the first fluid and the second fluid are guided to the mixing chamber by the guide body arranged inside the nozzle head, mixed and atomized, and the suction portion of the Laval nozzle shape is fed from the mixing chamber. By using the pressure mixing means of Laval nozzle shape, evenly flowing in and sucking the secondary air around the mixed fluid ejected at high speed, the fluid ejected from the diffuser is diffused by the pressure release and stalled. By preventing, it can inject in the state which has high straightness. Therefore, there is an advantage that the structure can be simplified by mixing the two fluids with one guide body. Moreover, as the mixed fluid ejection control means, the ejection state of the mixed fluid can be changed by changing to a guide body having different hole diameters and / or arrangement numbers of the two fluid flow holes. Furthermore, if the diameter of the Laval nozzle-shaped throat is changed, the straightness of the jet fluid can be changed.

According to the fifth aspect of the present invention, when the two-fluid injection nozzle is used as a burner, the mixture to be injected has very high straightness, and up to about half of the total length of the flame as blue fire, the remaining half. Can be a red flame with strong radiant heat. Therefore, for example, it is effective for use in applications in which a clogged portion caused by dust or slag generated in a melting furnace is locally heated and melted. Further, since combustion is started after jetting from the nozzle, there is an advantage that the structure is simple and maintenance is easy as a burner.

Also, replacement of the different pore sizes and / or the arrangement number of the flow holes of the guide body that is disposed within the Bruno Zuruheddo, or by changing the throat diameter of the Laval nozzle shape with the changes of the guide body, the combustion conditions of the burner Can be set.

  Next, specific embodiments of the two-fluid injection nozzle and the oil burner according to the present invention will be described with reference to the drawings.

FIG. 1 is an overall outline view showing a two-fluid injection nozzle according to the premise technique of the present invention. FIG. 2 shows a longitudinal sectional view (a) of the main part of the injection nozzle, and its AA sectional view (b) and BB sectional view (c). FIG. 3 shows a mechanism for controlling the fluid of the injection nozzle. A longitudinal sectional view is shown respectively.

The two-fluid injection nozzle 1 shown in these drawings includes an outer tube 2 and an inner tube 3 of a required length combined in a coaxial core, a first fluid jet port 12 provided at the tip of the inner tube, A needle valve (flow control valve 10) for controlling the flow rate at the ejection port 12, a nozzle head 20 provided at the tip of the outer tube 2 and having a Laval nozzle forming portion inside, and the inner tube 3 inside the nozzle head 20 And a flow rate setting mechanism 26 that can set the flow rate of the second fluid.

  The inner tube 3 with respect to the outer tube 2 includes a screw hole 4b formed coaxially inside a connection support fitting 4 in which a screw hole 4a is screwed and fixed to a rear end thread portion 2a of the outer tube 2, and an outer tube 2 is held concentrically by a receiving piece 5 that is equally divided into the inner circumference attached to the tip of 2 and provided with a projection, and a required space 7 is formed between the outer circumference and the inner surface of the outer tube 2. ing. A second fluid supply port 6 and its connecting pipe 6 'are attached to the rear part of the outer pipe 2 perpendicular to the side surface.

  Further, the inner tube 3 has a longer dimension than the outer tube 2, and a male screw portion 3 a is formed on the outer periphery of the rear end portion, and the male screw portion 3 a is fixed to the rear end screw portion 2 a of the outer tube 2. A lock nut 8 screwed into the screw hole 4b of the metal fitting 4 and screwed into the male screw portion 3a is brought into contact with the rear surface 4c of the connection support metal fitting 4 and fixed. The rear end portion of the male threaded portion 3a of the inner tube 3 is provided with a supply port 9 for the first fluid supplied into the inner tube 3 and its connecting tube 9a in a lateral direction, with the inner tube at the center. The first fluid introduction fitting 11 having the attachment screw hole 11a is screwed and fixed. The first fluid introduction metal fitting 11 is fixed so that a lock nut 8 ′ engaged with the male thread portion 3 a of the inner tube 3 is brought into contact with the front surface and is not detached from the end of the inner tube 3.

  On the other hand, as shown in FIG. 2, a fluid jet 12 is provided on the central axis at the distal end of the inner pipe 3, and the flow rate control valve 10 having an inner periphery of the fluid jet 12 as a valve seat 13. (Needle valve) is provided. In this flow control valve 10, a valve stem 14 having a needle valve body 14 a at the tip is inserted through a coaxial core from the rear end portion of the inner tube 3, and a male screw portion formed at the rear end portion of the valve stem 14. 14b is threadedly engaged with a valve stem operating screw hole 11c formed through the center of the first fluid introduction fitting 11, and a handle (not shown) is engaged with a square shaft portion 14d formed at the end of the valve stem 14. Then, by rotating the valve rod 14, the needle valve body 14 a is advanced and retracted with respect to the valve seat 13 by a screw number (pair), and the flow rate is adjusted. Reference numeral 16 in the drawing is an attachment member for attachment to equipment using the two-fluid injection nozzle 1, which is provided with a plurality of attachment holes (not shown) and is fixed to an intermediate portion of the outer tube 2.

  The nozzle head 20 is attached to the tip of the outer tube 2 with a coaxial core. As shown in FIG. 2, the nozzle head 20 includes a screwing attachment portion (female screw portion 21 a) to the end of the outer tube 2 of the cylindrical rear portion 21, and the inner tube 3 is connected to the tip of the outer tube 2. An extended portion 7a of the annular second fluid flow space 7 formed between the inner periphery of the outer tube 2 and the outer periphery of the inner tube 3 is received. The intermediate part of the nozzle head 20 has a diffuser through a constricted portion 23 (throat portion 23) from a trumpet-shaped suction portion 22 that contracts from the formation portion of the extension portion 7a of the flow space toward the axial center on the central axis. A Laval nozzle forming portion 25 leading to 24 is provided. Further, an air suction part 27 having an enlarged opening diameter is formed from the intermediate part to the front part so as to be connected to the diffuser 24.

  In the suction portion 22, a valve body portion 10 a formed at the distal end portion of the inner pipe 3 sets a gap between the extension portion 7 a of the flow space 7 of the second fluid so as to oppose the trumpet-like constricted wall surface 22 a. The trumpet-shaped restricting wall surface 22a and the valve body portion 10a (corresponding to the inner surface of the second fluid passage wall and the tip of the inner pipe in the present invention) provide a second fluid flow rate setting mechanism 26. Is formed. The setting operation in the flow rate setting mechanism 26 can set the flow rate of the second fluid appropriately by setting the gap by means described later.

  Further, the air suction part 27 is formed into a cylindrical shape having a required length with a larger diameter than the tip diameter of the diffuser 24 of the Laval nozzle forming part 25, and the cylindrical part is equally divided into a peripheral surface along the axis. A plurality of elongated air suction holes 28 are provided.

In the thus configured two-fluid injection nozzle 1, the water as a first fluid in use, using compressed air as the second fluid, will be described when used as a water spray nozzle.

  In this water spray nozzle, a pressure water supply pipe (not shown) is connected to the first fluid supply port 9 via the connection pipe 9a, and the connection pipe is connected to the second fluid supply port 6. A compressed air or steam supply pipe (not shown) is connected through 6 'to supply each fluid. Prior to use, a supply flow rate of the second fluid (compressed air or steam) is set. Regarding the setting of the supply flow rate of the second fluid (compressed air or steam), the tightening of the lock nut 8 fixed in contact with the rear surface 4c of the connection support fitting 4 is loosened, and the first fluid introduction fitting 11 is rotated. As a result, the inner pipe 3 integrally coupled with the first fluid introduction fitting 11 rotates, and the screw hole 4b (female screw portion) of the connection support fitting 4 and the male screw portion 3a of the inner pipe 3 are connected. The inner pipe 3 is directly advanced and retracted with respect to the connection support fitting 4 by a screw number (joint), and the valve body portion 10a at the tip of the inner pipe 3 constituting the flow rate setting mechanism 26 and the trumpet-shaped reduced wall surface in the nozzle head 20 The gap with 22a is set appropriately. When the flow rate setting is completed, the lock nut 8 is tightened to fix the inner tube 3 to the connection support bracket 4 for use.

  On the other hand, the pressure water supplied into the inner pipe 3 can adjust the injection flow rate by operating the flow rate adjusting valve 10 incorporated in the inner pipe 3. The flow rate control valve 10 has a handle or a servo motor having a positioning function attached to a square shaft portion 14d at the end of the valve rod 14 protruding from the rear portion of the pressure water (first fluid) introduction fitting 11 (or a tool such as a monkey). ), By rotating the valve stem 14, the needle valve body 14a at the tip of the valve stem 14 advances and retreats, and the gap between the valve seat 13 at the inner peripheral edge of the fluid jet 12 provided at the tip of the inner tube 3 The flow rate can be adjusted by adjusting.

  The operation of the water spray nozzle (two-fluid jet nozzle 1) thus configured will be described. The pressure water fed from the supply port 9 passes through the inner tube 3 from the jet port 12 at the tip of the suction port of the Laval nozzle shape portion 25. 22 erupts. On the other hand, compressed air (or steam) is fed from the supply port 6 into the flow space 7 inside the outer tube 2, and a set gap (a trumpet-like constriction) in the flow rate setting mechanism 26 from the extension 7 a of the flow space in the nozzle head 20. It is ejected to the suction portion 22 through a gap between the wall surface 22a and the valve body portion 10a at the distal end portion of the inner tube.

  The pressure water and compressed air (or steam) ejected to the suction part 22 in the nozzle head 20 are vigorously mixed at the Laval nozzle inlet (suction part 22), and are compressed by the throat part 23, which is the narrowest flow path. The fuel is accelerated to the above speed, passes through the diffuser 24, and is injected at an extremely high speed at the outlet 29. Due to the discharge force (injection force) of the air-fuel mixture passing through the outlet portion 29, a plurality of vertically formed portions around the air suction portion 27 provided at the nozzle tip portion as schematically shown in FIG. The ambient air is sucked in from the air suction hole 28, and the air flow f sucked around the air-fuel mixture g to be ejected is jetted in a surrounding state. As a result, the air-fuel mixture g injected from the nozzle tip can be prevented from diffusing at the nozzle tip outlet 30 and can be jetted with high straightness.

  For this reason, the water spray nozzle is different from the purpose in which the spray state of the sprayed water simply expands the diffusion range of the atomized spray as in the case of a general spray nozzle. Since the directivity is generated, the fluidity can be imparted by causing the surrounding airflow to travel along with the jet. Therefore, for example, it can be expected that the rectifying effect in the tower can be enhanced by using it for the spray nozzle of the temperature reducing tower. In addition, upward spraying can be performed.

The two- fluid injection nozzle 1 can be used as an oil burner by using fuel oil such as kerosene as the first fluid and compressed air (or steam) as the second fluid. Next, a case where an oil burner is used will be described.

  In this oil burner, the fuel oil supply pipe is connected to the first fluid supply port 9 via the connection pipe 9a, and the second fluid supply port 6 is compressed via the connection pipe 6 '. Air (or steam) supply piping is connected to supply each fluid. Prior to use, a supply flow rate of the second fluid (compressed air or steam) is set. Since the supply flow rate setting of the second fluid (compressed air or steam) is the same as in the case of the water spray nozzle, the description thereof is omitted.

  The fuel oil fed from the supply port 9 is jetted from the jet port 12 at the tip through the inside of the inner pipe 3 to the suction portion 22 of the Laval nozzle shape portion 25. On the other hand, compressed air (or steam) is fed from the supply port 6 into the flow space 7 inside the outer tube 2, and a set gap (a trumpet-shaped reduced wall surface) in the flow rate setting mechanism 26 from the flow space extension portion 7 a in the nozzle head 20. 22a and a gap formed by the valve body 10a at the distal end portion of the inner pipe).

  The fuel oil and compressed air (or steam) ejected to the suction part 22 in the nozzle head 20 are vigorously mixed at the inlet (suction part 22) of the Laval nozzle shape part, and compressed by the throat part 23 that forms the narrowest flow path. Then, it is accelerated to a speed higher than the speed of sound, passes through the diffuser 24, and is injected at an extremely high speed at the outlet. As shown in FIG. 4, due to the discharge force (injection force) of the air-fuel mixture g passing through the outlet portion 29, as in the case of the water injection, the air suction portion 27 provided at the nozzle tip portion surrounds the surroundings. The surrounding air is sucked from the air suction holes 28 formed in a vertically long shape at a plurality of locations, and the air flow f sucked around the air-fuel mixture g to be ejected is jetted in a surrounding state. As a result, the air-fuel mixture g injected from the nozzle tip outlet 30 is prevented from diffusing at the nozzle tip outlet 30 and is injected with high straightness. Accordingly, if an ignition means (ignition nozzle, not shown) is separately provided for the injection portion of the mixture g, and the mixture is ignited by the ignition nozzle when the injection of the mixture is started, it can be performed at high speed. The jetting air-fuel mixture can be burned.

  When the air-fuel mixture (combustion gas) ejected from the tip of the nozzle head 20 is burned in this way, a plurality of air suction holes 28 formed in a vertically long shape by the air suction part 27 provided at the nozzle tip 29 as described above. The air flow sucked around the air-fuel mixture to be ejected is injected in a state of being surrounded by the suction of air from the air. As a result, the air-fuel mixture injected from the nozzle tip outlet 30 is prevented from diffusing at the nozzle tip outlet 30 and is injected with high straightness without stalling. The state of combustion can be made to correspond to the state of use by adjusting the amount of fuel oil jetted by the flow rate adjusting valve 10. Of course, the air supply amount may be adjusted on the compressed air supply piping side.

As for the flame of the air-fuel mixture that is injected and burned in this way, up to about half of the total length of the flame becomes blue fire due to high-speed combustion, and the other half becomes red fire with strong radiant heat. According to the oil burner, it is possible to radiate a flame having such straightness, so that, for example, a closed portion due to dust or slag generated in a melting furnace in a waste treatment facility is locally heated and melted. It is used for processing purposes and has great effect. In addition, it is effective when so-called local heating is required. Also, the O Irubana Since burning the fuel-air mixture after ejected from the nozzle, the nozzle is not exposed to high temperatures, there is an advantage of avoiding damage due to heat.

It will now be described implementation form of two-fluid injection nozzle of the present invention.
FIG. 5 shows a cross-sectional view (a) of a main part of a two-fluid injection nozzle according to an embodiment of the present invention and an enlarged cross-sectional view (b) taken along CC line.

The two-fluid injection nozzle 1A according to the present embodiment is the same as the above-described two-fluid injection nozzle 1 in its basic configuration, but is different in a configuration incorporating a guide body as a two-fluid mixing means. The description will focus on the different parts. Accordingly, the same or similar components as those of the above-described two-fluid injection nozzle 1 are denoted by the same reference numerals and detailed description thereof is omitted.

  The two-fluid injection nozzle 1A is configured such that the inner tube 3 and the outer tube 2 are disposed inside a nozzle head 20A attached to the tip of a double tube composed of an inner tube 3 and an outer tube 2 that supply two fluids individually. The coupling part piece 40 fitted and attached to the inner pipe end part 3 'and the outer pipe end part 2' and the guide body 50 for mixing the two fluids are incorporated. ing.

Similarly to the nozzle head 20 , the nozzle head 20 </ b> A has a Laval nozzle shape 25 inside and is provided with an air suction portion 27 at the tip. This nozzle head 20A is the same as the inner and outer tubes 3 and 2 by screwing a female screw portion 21a formed on the inner periphery of the base end portion 21 'with a male screw portion 2a formed on the outer periphery of the distal end portion of the outer tube 2. It is detachably mounted along the axis. On the other hand, the nozzle head 20A has a peripheral end position at the rear end position of the external thread 2a formed on the outer tube 2 in order to maintain the function of fitting and fixing a guide body 50, which will be described later, in a removable state. A groove portion 2c having an appropriate width is provided on the surface, and a stop ring 46 is detachably attached to the rear end of the female screw portion 21a on the inner periphery of the base end portion 21 '. The stop ring 46 is fitted into the groove 2c, and the stop ring 46 is coupled to the base end 21 'side by a screw piece 47 for fixing through screw holes 2d provided at a common position at a plurality of positions from the outer peripheral surface. To be fixed. The stop ring 46 is divided in the circumferential direction so as to be fitted into the groove 2c.

  As shown in FIG. 5, the coupling piece 40 is formed with a front half portion 41 in the axial direction in the shape of a bowl having a diameter smaller than the outer periphery of the outer tube 2, and is fitted to the inner diameter of the outer tube 2. A recess 43 for receiving the end portion of the inner tube 3 from the rear end is formed in the axial center with the rear portion 42 having an outer shape capable of forming the inner space of the outer tube 2 and the required gap portion 35. . A first fluid circulation hole 44 is formed through the recess 43 to the center of the front surface, and a front portion of the circulation hole 44 is formed in an enlarged manner. Further, around the central circulation hole 44, communication holes 45 connected to the gap portion 35 are formed at a plurality of positions at equal rotational angle positions in the circumferential direction in parallel with the axis.

  Further, as shown in FIG. 5, the guide body 50 has an outer shape that is inserted and fixed in a guide body fixing step portion 21 c formed in the nozzle head 20 </ b> A with the latter half formed in a thick bowl shape in the axial direction. The front half 52 has an outer diameter smaller than that of the fitting portion 51, and a hook-like protruding portion 53 is formed at the front end. In the central part, a concave part 54 is provided which is a bottomed hole along the axis with a required length from the rear end face. The concave portion 54 is formed to have a diameter that is substantially the same as or slightly larger than the enlarged diameter portion of the flow hole 44 provided in the coupling piece 40, and has a small diameter flow hole 55 toward the outer periphery of the front half 52 at the inner end portion. Are divided into a plurality of portions and are formed radially. In addition, a flow hole 56 is formed in the fitting portion 51 at a position that coincides with the plurality of communication holes 45 provided in the coupling piece 40 at the time of assembly. The front end is arranged so as to open above the outer peripheral surface of the front half 52. The flow hole 44 (communication to the inner tube side) communicating with the recess 54 and the flow hole 56 (communication to the outer tube side) provided in the fitting portion 51 are provided so as to be at the same rotation angle position. preferable. However, it is not limited to this.

  In the two-fluid injection nozzle 1 </ b> A configured as described above, the distal end portion 3 ′ of the inner tube 3 is fitted into the concave portion 43 of the coupling portion piece 40, and the coupling portion piece 40 is fitted to the end portion of the outer tube 3. As a result, the inner tube 3 and the outer tube 2 are held together on the same axis. In this state, the guide body 50 is applied to the front surface of the connecting piece 40, and the base end portion 21 'of the nozzle head 20A is attached by screwing the female screw portion 21a to the male screw portion 2a of the outer tube 3. The guide body side of the communication hole 45 has a circumferential groove structure, so that when the nozzle head 20A is mounted on the outer tube 3, the communication hole of the guide body 50 and the connection piece 40 are connected to each other. It is not necessary to match 45.

  The guide body 50 couples the nozzle head 20A to the outer tube 2 by a screw number (joint), and is fastened by a screw piece 47 by fitting the stop ring 46 and the groove 2c at the rear end of the base end 21 '. When fixed, it is sandwiched between the step surface of the guide body fixing step portion 21c in the nozzle head 20A and the front surface of the coupling portion piece 40, and the rear surface of the guide body 50 is fixed in close contact with the front surface of the coupling portion piece 40. The first fluid or the second fluid does not leak at the intimate portion.

  When the guide body 50 is assembled in the nozzle head 20A in this manner, the two-fluid injection nozzle 1A is positioned in front of the suction portion 22 of the Laval nozzle shape 25 formed inside the nozzle head 20A as shown in FIG. , An annular space is formed between the outer periphery of the front half 52 of the guide body 50 and the inner wall surface of the nozzle head, and this space forms a mixing chamber 58. A flange-shaped protrusion 53 formed at the front end of the guide body 50 forms a narrow annular passage 59 between the peripheral wall surface of the suction portion 22 and a portion communicating with the suction portion 22 from the mixing chamber 58. The fluid mixed through the annular passage 59 is ejected from the entire circumference to the suction portion 22 of the Laval nozzle shape 25.

The two-fluid injection nozzle 1A configured as described above connects a fluid supply pipe to each of the inner and outer pipes 3 and 2, supplies the first fluid to the inner pipe 3 side, and supplies the second fluid to the outer pipe 2 side. Then, the first fluid flows into the concave portion 54 of the guide body 50 from the flow hole 44 of the coupling piece 40 and is ejected to the mixing chamber 58 through the small-diameter flow holes 55 provided radially. Further, the second fluid supplied to the outer tube 2 side is ejected to the mixing chamber 58 through the plurality of communication holes 45 of the coupling piece 40 from the corresponding flow holes 56 of the guide body 50. When both the flow holes 55 and 56 are provided at the same rotation angle position, both the fluids collide with the first fluid and the second fluid ejected into the mixing chamber 58 at the same time as the ejection. When mixed, the first fluid is water and the second fluid is gas (compressed air), and the ejected water is atomized by collision mixing with the compressed air and flows out to the suction part 22 of the Laval nozzle shape 25, and further mixed vigorously. Then, it is compressed by the throat portion 23 and accelerated, and injected from the diffuser 24 at the outlet portion 30 at an ultra high speed. Note that the air suction part 27 at the tip can suck ambient air from an air suction hole 28 provided in the periphery and perform injection with high rectilinearity like the two-fluid injection nozzle 1 described above .

The two-fluid injection nozzle 1A of this embodiment can be used as an oil burner, similar to the two- fluid injection nozzle 1.

When used as an oil burner, like the two-fluid injection nozzle 1 , fuel oil such as kerosene is supplied as the first fluid and compressed air (or steam) is supplied as the second fluid. In addition, regarding the setting of the supply flow rate of each fluid, setting the hole diameters of the first fluid-side flow hole 55 and the second fluid flow hole 56 provided in the guide body 50, and setting the number of holes. Alternatively, it can be changed by setting the hole diameter and determining the number of flow holes. Accordingly, a plurality of different diameters of the flow holes 55 and 56 are prepared in advance with respect to the guide body 50 having standard conditions set, and the optimum one is selected. When the number of holes is changed, the communication hole 45 in the connecting piece 40 is replaced with a corresponding one.

  At the time of replacement by changing the guide body 50, the threaded portion of the nozzle head 20A is disassembled by releasing the connection by the screw piece 47 fastened to the stopper ring 46 fixed to the inner end portion of the base end portion 21 'of the nozzle head 20A. Make it possible. Thereafter, when the nozzle head 20A is removed from the outer tube 2, the guide body 50 (and the connecting piece 40) can be easily removed. Therefore, the guide body 50 can be replaced with the selected flow amount and assembled as described above. Can perform the required injection. Furthermore, if necessary, the nozzle head 20A can be used by replacing the throat 23 in the Laval nozzle-shaped portion 25 with a modified diameter if the structure of the mounting portion is aligned.

  In the close combination of the guide body 50 and the connecting piece 40, when the number of the flow holes 55, 56 is changed, or in order to facilitate assembly, for example, a contact surface on the guide body 50 side ( You may make it use what formed the cyclic | annular groove | channel (not shown) which each flow hole 56 connects in the rear surface. If it carries out like this, the flow of the 2nd fluid can be made to respond | correspond without making the position of the communicating hole 45 provided in the coupling | bond part piece 40 and the flow hole 56 of the guide body 50 correspond. The communicating annular groove may be provided on one side of the coupling portion.

According to the two-fluid injection nozzle 1A (oil burner) of the present embodiment configured as described above, it is possible to provide a simple structure capable of exhibiting a target injection function without incorporating a movable mechanism.

  In the above description, one embodiment of the two-fluid injection nozzle has been described. However, the present invention is not limited to this, and it is needless to say that the shape structure can be changed within the technical scope of the present invention.

Overall outline drawing of two-fluid injection nozzle according to the premise technique of the present invention Longitudinal sectional view (a) of the main part of the injection nozzle, and its AA sectional view (b) and BB sectional view (c) A longitudinal sectional view showing a mechanism for controlling the fluid of the injection nozzle Schematic showing the operating mode of the jet fluid at the tip of the nozzle head The principal part sectional view (a) of the two fluid injection nozzle concerning one embodiment of the present invention, and its CC view expanded sectional view (b)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1A Two-fluid injection nozzle 2 Outer pipe 3 Inner pipe 4 Connection metal fitting 6 Supply port of 2nd fluid (compressed air or steam) 7 Flow space 7a Extension part of flow space 8 Lock nut 9 1st fluid (pressure water or fuel (Oil) supply port 10 Flow rate adjusting valve 11 First fluid introduction fitting 14 Valve rod 20, 20A Nozzle head 21 'Nozzle head base end 22 Suction part 23 Throat part 24 Diffuser 25 Laval nozzle shape part 26 Flow rate setting of second fluid Mechanism 27 Air suction portion 28 Air suction hole 30 Nozzle tip outlet 40 Joint piece 44 Flow hole 45 Communication hole 46 Stop ring 50 Guide body 51 Guide body fitting portion 52 Front half portion of guide body 54 Recess portions 55 and 56 Flow holes 58 Mixing chamber

Claims (7)

  Inside the nozzle head attached to the end of the double pipe is a guide body provided with a first fluid flow hole communicating with the inner pipe of the double pipe and a second fluid flow hole communicating with the outer pipe. In the mixing chamber formed between the peripheral surface of the guide body and the inner wall of the nozzle head, the two fluids are mixed and flow into the suction part of the Laval nozzle shape, and the Laval nozzle shape diffuser outlet front position In addition, a two-fluid jet nozzle characterized in that a plurality of vertically long air suction holes are provided around the axis to surround the jet flow path of the mixed fluid. The guide body has a second half in the axial direction as a fitting portion in the nozzle head, a front half having an outer diameter smaller than that of the fitting portion, and a hook-like projecting portion formed at the front end. The guide body communicates with the inside of the inner pipe. A concave portion is provided, and a plurality of small-diameter flow holes are radially divided from the concave portion toward the outer periphery of the first half, and a plurality of flow holes communicating with the inside of the outer tube are provided in the fitting portion in parallel with the axis. The two fluids ejected from both the flow holes between the inner wall surface of the nozzle head and the outer peripheral surface of the front half are closely fixed to the tip of the double pipe by the nozzle head at the fitting portion. mixing chamber is formed, the two-fluid injection nozzle according to configured claim 1 as the annular ejection passage of the mixed fluid with the flange-like projecting portion by the suction portion internal surface of the Laval nozzle shape is formed. Wherein the guide body, and the distribution hole and the outer tube communicating the fluid passing holes of the inner tube communicating, two-fluid injection nozzle according to claim 1 or 2 are provided at the same circumferential angle. 2. The two-fluid injection nozzle according to claim 1 , wherein the injection flow rate is set by changing a throat diameter of a Laval nozzle together with a change in the diameter and / or number of flow holes provided in the guide body.   A guide body having a circulation hole for fuel oil supplied through the inner pipe of the double pipe and a distribution hole for compressed air supplied through the outer pipe is disposed inside the nozzle head attached to the end of the double pipe. The mixing chamber formed between the peripheral surface of the guide body and the inner wall of the nozzle head communicates with the suction portion of the Laval nozzle shape, and is vertically elongated along the axis at the Laval nozzle shape diffuser outlet front position. A plurality of air suction holes are arranged, and air is sucked from the air suction holes around the mixture of fuel oil and air ejected from the diffuser, so that a highly straight flame is generated by the mixture to be injected. An oil burner characterized by having an obtained structure. 6. The oil burner according to claim 5 , wherein the guide body is configured so that a flow rate of two fluids can be set by changing a hole diameter and / or a number of the flow holes provided. The oil burner according to claim 5 , wherein the combustion amount and the flame amount are set by changing the throat diameter of the Laval nozzle as well as changing the diameter and / or number of flow holes provided in the guide body.

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