JPS5847903A - Method and burner for evaporating and burning liquid fuel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for vaporizing and combusting liquid fuel by mixing air, gas or water vapor with atomized fuel, and a method for vaporizing and combusting a liquid fuel, and a method comprising an outlet tapering conically at the tip. It has a jacket pipe, and a spray nozzle is arranged in front of the outlet of the jacket pipe, and a notch is provided on the outer circumferential surface of the nozzle. The invention relates to a burner for liquid fuel starting from a ring-shaped chamber connected to a formed compressed gas supply and opening at the other end into the outlet chamber of a spray nozzle.

According to West German Patent Publication No. 1551638,
Burners are known in which, in front of the pneumatic oil atomization nozzle, the air is mixed into the jetting oil in an air supply chamber through a cut-out notch, and intensive mixing is achieved by swirl formation.

A method for atomizing and combusting a liquid fuel and a burner operated by this method are known from JP 12656439 A1, in which high-pressure air is injected into the first part of the oil injection nozzle. In the process, the liquid fuel is drawn in and atomized, and this premix is prepared so that it can actually be combusted without soot by introducing secondary air. Ru.

Burners according to the state of the art have in common the drawbacks caused by atomization of the fuel or by an exchange of kinetic energy between the liquid fuel stream and the high-pressure air, which is divided into partial jets.

This known method of operation presupposes large flows of highly compressed air.

Starting from this state of the art, the present invention not only can be implemented easily without the above-mentioned disadvantages, but also provides a very high temperature chemistries, non-luminous flame, which does not contain any soot. It is based on the object of the present invention to disclose methods and burners of the type mentioned at the outset for producing associated combustion.

The task is to atomize the fuel under high pressure with an atomizing nozzle and to further disperse the droplets thus formed by a jet of air or other gas at a static pressure lower than the vapor pressure of the liquid to be atomized and at a velocity higher than the speed of sound. The solution is to divide and evaporate the problem. For example, if the fuel is atomized through a spray nozzle at a medium pressure of 5 to 20 bar, the air or other gas jet has a low pressure compared to this pressure, for example 2.5 bar initially; This varies, for example, from 1 to 2 times the rate. This fuel vapor-gas premixture is mixed with secondary air at a low prepressure and completely combusted in the burner tube. Extremely fine atomization is caused by a relatively low volume air- or gas jet having a velocity higher than the speed of sound.The atomizing air or gas is passed through a nozzle into a stream of pre-atomized fuel. through which the nozzle has the characteristics of a Laval tube, i.e. the flow #I'f
The compressed gas is led into a chamber with a continuously tapering cross-section, and after passing through the narrowest cross-section it reaches a continuously expanding chamber, from which it flows into the opening of a jet nozzle;
At that time, due to the compression pressure still present in the jet or the expansion, 1
is converted to a speed greater than twice the speed. The gas jets exiting at supersonic speeds create strong compressive shocks, which periodically generate strong negative pressures. This interaction of pressurization and negative pressure causes the already finely atomized fuel confinement droplets to be further divided into levels below 1 μm, which are further divided in front of the nozzle due to the significant surface area expansion achieved by the confinement. Complete gasification takes place in conjunction with the resulting negative pressure. This is because the droplet and vapor pressures are greater than the ambient pressure during the negative pressure phase.

According to the present invention, liquid fuel is vaporized and burned.

The method allows the combustion of liquid fuels with viscosity ranging from low to very high viscosities, and therefore particularly heavy fuel oils as well.
After preheating to 0° C., it can be combusted with a homogeneous flame and free of 'f'f.

Regarding the device, the feature on which the present invention is based is that the spray nozzle is in linear contact with its outer peripheral surface to the inner surface of the tip of the jacket tube, which tapers into a conical shape, so that one end of the notch The chamber extends tapering from the anterior area of the chamber into the narrowest cross-section of the notch and the narrowest cross-section of the notch.
This is solved by having a chamber that widens from the cross section into the area behind the other end of the notch. The geometry in the area is cut along the central plane and can therefore be represented as a bisected Laval tube.

Advantageously, the spray nozzle has a spherical outer circumferential surface at its tip. However, it is also possible for the spray nozzle or its tip to be provided with circumferential surfaces corresponding to the jacket surfaces of the two truncated cones, the front truncated cone having a diagonal angle greater than the cone angle of the jacket tube and the rear cone having a diagonal angle larger than the cone angle of the jacket tube. The platform has a diagonal angle smaller than that of the rhinoceros tube.

The notch tapers into a conical shape and extends parallel to the inner peripheral surface of the tip of the tube.

The longitudinal axis of the notch may extend at an angle to the longitudinal axis of the tube and the atomizing nozzle, so that the compressed gas exiting at supersonic speeds is separated from the primary oil vapor around the central axis. The premix is subjected to turbulent flow conditions resulting in dynamic mixing.

According to another feature of the invention, the notch is formed on the outer circumferential surface 9 of the spray nozzle.
Alternatively, it may be provided on the inner circumferential surface of the tip of a conically tapered jack-nosed tube, in which case the geometry remains unchanged in other respects.

If the cross-sectional area of the notch is larger than the sum of the cross-sectional area of the notch and the cross-sectional area of the narrowest part of the notch, it is Yuri.

It is also possible to provide one notch instead of several notches.
It is J-Noh. It may also be replaced by a notched groove, which is extremely important from a production technology standpoint.

A dam plate with 1 #44 central through holes is provided at regular intervals in front of the outlet of the burner tube, through which the fuel vapor-gas mixture mixed with secondary air flows into the burner tube. The through opening of the dam plate is constricted in the shape of a trumpet when viewed in the direction of flow, thus providing a feature of the nozzle that reduces noise generation.

The distance of the dam plate from the outlet of the jacket tube and the cross-sectional area of the opening are such that the secondary air has a high velocity, e.g.
It is advantageous to select ↓ that reaches ~40 m/sec.

According to another feature of the invention, the cylindrical tube of the burner is surrounded by another jacketed conduit to form a ring-shaped chamber,
This chamber has an outlet at its conically tapered tip and is connected to a gas supply at its rear end. In this way, liquid fuel and gaseous fuel can be combusted alternately and simultaneously in the burner. This additional jacket tube, as well as the jacket tube of the burner, provides insulation for the liquid fuel supply. The device can therefore operate with hot air without concern for oil evaporation or cranking in the supply conduit.

In this embodiment as a combination burner, operation is first started with gas and then switched to heavy oil operation after achieving a temperature of about 800° C. or higher in the burner. This embodiment of the burner reveals the possibility of use in a low-temperature controlled combustion chamber, e.g. for heat treatment, drying, generation of hot water, etc., since it exits the burner tube without contamination. The compressed air produced cools the atomizing nozzle at the same time, so that the nozzle is protected from the effects of temperature radiation from the burner tube and even during regulatory time intervals of interruptions in the supply of fuel or compressed gas. .

Systems with such high conversion characteristics are accompanied by violent and noisy production. In order to prevent this, the present invention proposes that the burner tube be provided with holes distributed over its entire circumferential surface, and that the burner tube be surrounded by the sleeve tube or the burner block while being held in a ring-shaped chamber. Through this, a part of the sound waves is conducted into the cylinder chamber and is attenuated by several reflections.

It is advantageous if the outlet cross-section of the burner tube widens in a trumpet-like manner in the direction of flow, so that the formation of peripheral swirls, which can cause noise, is reduced or prevented.

According to another proposal of the invention, in the area of the burner tube, the front part of the dam plate is provided with a hole opening into the annular chamber. The combustion air flowing out through the holes mixes with the gas stream exiting through the holes in the burner tube, thereby damping the impulse of the gas stream and lowering its peak temperature.
A soundproofing material is provided in a ring-shaped chamber in the rear region of the burner tube, which further reduces the strength of the sound waves.

According to another feature of the invention, the dam plate is tightly connected to the tube piece surrounding it, the outer diameter of the bow tube piece approximately corresponding to the inner diameter of the burner tube. The tube piece is fitted as tightly as possible to the inner wall of the burner tube. Its function is to keep the flow of air between the dam plate and the inner wall of the pipe low without using a backing member, and to keep the flow of air low when the air flows through the ring-shaped slit that inevitably forms. The idea is to mix the air at a location that is sufficiently far away from the base of the generated flame when viewed in the direction of the air. This avoids the formation of turbulence in the area of the dam plate and the cooling of the flame gases near the dam root, which would otherwise form at the dam plate.

It is advantageous if the tube piece has a conically tapering section at its front end. This area has the effect of reducing the velocity of the air flowing through the annular slit between the tube piece and the burner tube 6 so that the air no longer acts on the flame gas flow.

According to a further proposal of the invention, the front end of the ignition electrode extends with a gap maintained as far as the conically tapered region of the tube piece as counter electrode.

In this way, ignition is ensured through the defined distance between the electrode and the tube piece in an area that is not at risk from increased temperatures.

Next, the present invention will be explained in detail with reference to the accompanying drawings.

In the embodiment according to FIGS. 1-6, the burner tube is 1, the burner mounting flange is 2, the connecting casing is 2a and the blind-
7 lunges are represented by 3. A combustion air supply conduit 4 opens radially into the burner tube 1, and a fuel oil supply conduit 5 and a compressed air supply conduit 6 are connected to the burner, which will be explained in more detail below.

The burner has a jacket tube 7 which tapers conically at its front end and is provided with an outlet 18, in front of which a spray nozzle 10 is arranged. Spray nozzle 1
0 has a spherical outer peripheral surface at its front end, and with this outer peripheral surface,
It is in contact with the inner surface of the front end of the jacket tube 7, which is tapered into a conical shape. This area of the spray nozzle 10 is provided with a notch 16 or cut-out groove on its outer circumferential surface, one end of which is connected to the compressed air, the liquid distribution chamber, formed by the spray nozzle 10 and the jacket tube 7. The ring-shaped chamber 9 used for this also starts and is connected at its other end with the outlet chamber of the spray nozzle 10.

The kneading contact between the spherical outer circumferential surface of the spray nozzle 100 and the linear inner surface of the front end of the conically tapered jacket tube 7 causes the front area of one end of the notch 16 and the back area of the other end of the notch 16 to be separated. One cavity is formed in each case, both cavities 17 having the same geometrical shape.The notch 16 is formed in the jacket surface of the front end 12 of the conically tapered jacket tube 7. They run parallel to each other, or, as is clear from FIG. The geometry in the area of the crimp line of the injection nozzle 10 for the tip pressure of the conically tapering jacket tube 7 is cut along the central plane. Therefore, it is a Laval tube divided into two equal parts.

The nozzle holder of the burner is designated 8 into which an oil supply conduit 5 opens.

An oil distribution chamber 11 is arranged inside the nozzle holder 8 .

A dam plate 13 with a central through hole 14 is provided at a constant interval in front of the outlet 1-8 of the jacket pipe 7, and this also serves as a support part 15 which also serves as a spacer. Supported by

The operation of the burner takes place in that the liquid fuel supplied via the supply conduit 5 reaches a distribution chamber 11 and is fed from this chamber under high pressure to the spray nozzle 10. The resulting droplets are further atomized by the compressed air flowing into the annular chamber 9 via the supply conduit 6, ie the compressed air is divided through the notch 16 into a high air jet. At this time, the speed is higher than the speed of sound. The droplets further divided in this way are further evaporated due to the formation of an aerodynamic negative pressure, during which time they mix with the fuel vapor-air mixture and the secondary air at a low pre-pressure and are then used in the burner. Secondary air is introduced into the burner tube 1 via the supply conduit 4, ie into the annular chamber surrounding the burner.

Due to several steps of atomization and vaporization and intensive mixing with the combustion air, a very hot, stoichiometric, aluminous fluid is created in the burner tube 1, in which case the fuel burns completely free of soot. do.

In the embodiment according to FIGS. 4 and 5, a notch 16 is provided on the inner circumference of the front end 12 of the conically tapered jacket tube 7, with a geometrical cross-section that is crucial for the functionality of the system. Provided to maintain the state. In this embodiment, instead of a spherical circumferential surface, two types of truncated conical outer circumferential surfaces are provided, the front truncated cone having a vertical angle larger than the cone angle of the jacket tube, and the rear truncated cone having a vertical angle larger than the cone angle of the jacket tube. The truncated cone has a smaller diagonal angle than that of the jacket tube.

The compressed air supplied via the supply conduit 6 for finely atomizing the liquid fuel cools the atomizing nozzle 1o, so that it is protected from the effects of thermal radiation from the burner tube 1.

In the embodiment according to FIG. 6, the through hole 1 of the weir stop plate 13
4 has a trumpet-shaped constriction.

In this embodiment, the jacket tube 1 of the burner is surrounded by a further jacket tube 21, thereby forming a ring-shaped chamber 2.3. An outlet 22 is provided at the front end of the conically tapering jacket tube 21 . The annular chamber 23 is connected via a supply conduit 20 to a gas supply.

This embodiment makes it possible to burn liquid fuel and gaseous fuel alternately or simultaneously in the burner. Thus, for example, when burning heavy oil, the system is started with gas or light oil and then proceeds to burn the heavy oil.

Both the jacket tube 21 and the jacket tube 1' of the burner act as a heat-insulating part of the liquid fuel supply line 5, so that the entire installation can be operated with hot air, with the fuel being evaporated or evaporated in the supply line 5. There is no risk of decomposition.
As is clear from FIG. 7, the burner tube 1 is provided with holes 25 over its entire circumferential surface in order to reduce the noise of the burner. The burner tube 1 is surrounded by a sleeve tube 24, which may be the inner circumference of the burner lock.

A part of the sound waves passes through the hole 25 and reaches the burner tube 1 and the sleeve tube 2.
4 and is attenuated by several reflections. The opening 28 of the burner tube 1 widens in the shape of a trumpet in the direction of flow, which reduces or prevents the formation of peripheral swirls which can cause noise generation.

Seven dam stop plates 1 seen in the flow direction in the area of the burner pipe 1
A hole 26 is provided in the front part of the burner tube 1.
and a ring-shaped chamber between the sleeve tube 24 and the sleeve tube 24. The combustion air exiting through this hole 26 mixes with the gas stream exiting through the hole 25, the impact of which is attenuated and the peak temperature reduced by the upper part. soundproofing material 2
7 is provided, which further reduces the sound intensity.

Taken together, these measures achieve a reduction in noise generation of 15-20 dB.

As is clear from FIG. 8, the dam plate 13 may be closely connected to the tube piece 29 surrounding it, which
Is the outer diameter of 9 the same as the inner diameter of burner tube 1? ! Match. At its rear end, viewed in the flow direction, the tube piece 29 is provided with a conically tapering section 3.0. This embodiment avoids the formation of swirls in that area and the cooling of the flame gases in the vicinity of the dam plate 13, which could lead to the formation of stings in the dam plate 13.

An ignition electrode 31 extends into the burner tube 1 and is fixed in the ignition plug socket of the burner cable. The ignition electrode 31 is surrounded by a ceramic insulator 33 at the through hole in the dam plate 13 . The front end of the ignition electrode 31 extends, maintaining a gap in the housing, into a conically tapering section 30 of the tube piece 29, which serves as a counter electrode.

[Brief explanation of the drawing]

The accompanying drawings represent embodiments of the invention; FIG. 1 is a partial cross-sectional view of a burner of the first embodiment, FIG. 2 is a cross-sectional view of a jacket tube of the burner with spray nozzles, and FIG. 2 is a front view, FIG. 4 is a cross-sectional view of a similar but modified embodiment to FIG. 2, FIG. 5 is a front view of FIG. 4, and FIG. 6 is a second embodiment. A partial cross-sectional view of a burner in the form of a stream, FIG.
The figure shows a cross-sectional view of an embodiment of the burner according to FIG. 1 with a dam plate surrounded by a tube piece. 1...Burner pipe, 7...Jacket pipe, 10...
Spray nozzle, 12...Tip of jacket pipe, 13...
・Damming plate, 14...through hole, 16...notch,
17... Chamber, 18... Outlet, 20... Supply conduit,
21... Jacket pipe, 22... Outlet, 23... Ring-shaped chamber, 24... Sleeve pipe, 25, 2, 69.・
Hole, 27... Soundproofing material, 28... Opening, 2, 9...
Tube piece, 30... conically tapering area, 31
...Point electrode Fig, 2 17 Fig, 4 Procedural amendment (method) (spontaneous), October 2, 1981 Mr. Commissioner of the Japan Patent Office 1, Indication of the case, Patent Application No. 143488, 1982, 2, Invention Name of method for vaporizing and combusting liquid fuel and No. 3,
Relationship with the case of the person making the amendment Patent applicant. - Togesel Shaft 4, Sub-Agent & Subject of Amendment (1) Drawing (2) - Person Certificate 7, Contents of Amendment (1) and (2) are both as attached. However, 1) is an engraving of the drawing.

Claims (1)

[Claims] 1. In a method of evaporating or burning liquid fuel by mixing air, gas, or water vapor with atomized fuel, the fuel is sprayed under high pressure with a spray nozzle, thereby forming a mist. evaporation and combustion of a liquid fuel, characterized in that the resulting droplets are further broken up and evaporated by a jet of air or other gas at a static pressure lower than the vapor pressure of the liquid to be atomized and at a velocity higher than the speed of sound; How to do it. 2. The method according to claim 1, wherein the particles are evaporated by the formation of an aerodynamic negative pressure shock. 5. Fuel (steam-gas pre-mixture) near low preliminary pressure.
3. The method as claimed in claim 1, further comprising mixing with air and complete combustion in the burner tube (1). 4. It has a jacket tube with an outlet that tapers into a conical shape at the tip, and a spray nozzle is arranged in front of the outlet of the jacket tube, and a notch is provided on the outer circumferential surface of the nozzle. one end of which is connected to the compressed gas supply formed by the atomizing nozzle and the jacket tube, and the other end opening into the outlet chamber of the atomizing nozzle. In a burner for carrying out a method of vaporizing and combusting liquid fuel of the type described above, the tip (12) of a jacket pipe (7), on the outer circumferential surface of which is a spray nozzle [10], extends conically and taperingly. a chamber (17) and a notch (16) which are in linear contact with the inner surface of the notch (16), thereby tapering from the area in front of one end of the notch (16) into the narrowest cross-section of the notch (16); A burner for vaporizing and burning liquid fuel, characterized in that it has a chamber C17)7jX configuration extending from the narrowest cross-section of the notch (16) into the rear area of the other end of the notch (16). 5. The device according to claim 4, wherein the spray nozzle (10) has a spherical outer peripheral surface at its tip. 6. The spray nozzle # (10) has an outer peripheral surface corresponding to the outer peripheral surface of two kinds of truncated cones at its tip, the front truncated cone has a diagonal angle larger than the cone angle of the jacket pipe, and the rear one has a diagonal angle larger than the cone angle of the jacket pipe. 5. A device according to claim 4, wherein the truncated cone has a smaller diagonal angle than the ribs of the jacket tube. Claims 4 to 6, wherein the Z notch (16) is parallel to the inner circumferential surface of the tip of the jaguette tube (7), which extends in a tapered conical shape. Device. 8. The longitudinal axis of the notch [16] extends at an angle to the longitudinal axes of the jacket tube (7) and the spray nozzle (10). Equipment described in Section. 9] - A jacket pipe (7) in which the notch (16) extends tapered into a conical shape instead of the outer peripheral surface of the spray nozzle (0)
The device according to any one of claims 1 to 8, wherein the device is provided on the inner circumferential surface of the tip (12) of the device. 10. The cross-sectional area of the outlet (18,) is larger than the sum of the cross-sectional areas of the narrowest part of the notch (16).
The device according to any one of Items 1 to 9. 11. The device according to any one of claims 4 to 1o, wherein one notch (16) is provided. 12. Device according to any one of claims 4 to 11, characterized in that the notch (16) is replaced by a cutout groove. 13. In front of the outlet (18) of the jacket pipe (1), a damming plate (13) having a central through-hole (14) is provided at a certain interval. The device according to any one of clauses 12. 14. Claim 13, wherein the through hole (14) of the dam plate (13) is narrowed into a trumpet shape when viewed in the flow direction.
Table listed in section - 〇15㇠ = Suno jacket pipe (7) is similar to other jacket pipe (7)
21) to form a ring-shaped chamber (23);
This chamber has an exit (22) at its conically tapered tip.
15. Device according to claim 4, characterized in that it has a rear end connected to a supply conduit (20). 16. The burner tube (1) is provided with holes (25) distributed over its entire circumference and is held in a ring-shaped chamber by the slide tube (2'4) or the inner jacket surface of the burner block. Apparatus according to any one of the enclosed claims 4 to 15. 1Z The opening (28) of the burner tube (1) widens in a trumpet shape when viewed in the flow direction.Claims 4 to 1
6. The device 218 according to any one of clauses 6, in the area of the burner pipe (1), in front of the dam plate (13), a ring-shaped ring between the burner pipe (1) and the sleeve pipe (24). 18. Device according to any one of claims 4 to 17, characterized in that it is provided with a hole (26) opening into the chamber. 19. Device according to any one of claims 4 to 18, characterized in that in the rear area of the burner tube (1) a soundproofing material (27) is provided in the cage/gang-shaped chamber. . 20; The dam plate (13,) surrounds the pipe piece (2
9), and the outer diameter of the tube piece (29) is 6.
20. The device according to any one of claims 4 to 19, which substantially corresponds to the inner diameter of the burner tube (1). 21. The device according to claim 20, comprising an extending section (30).22.Ignition electrode (,3) projecting into the burner tube (1).
1), and the front end of this electrode is 1. The conically tapering section (30) of the tube piece (29) as counter electrode
22. A device according to any one of claims 4 to 21, wherein the device extends into the gap under the gap.