WO1994025798A1

WO1994025798A1 - Device for whirling diffusion of combustion air for turbo burner

Info

Publication number: WO1994025798A1
Application number: PCT/KR1993/000075
Authority: WO
Inventors: Jin Min Choi
Original assignee: Jin Min Choi
Priority date: 1993-04-30
Filing date: 1993-08-20
Publication date: 1994-11-10
Also published as: AU4984893A; RU2113656C1

Abstract

A device for whirling diffusion of a composite combustion air for a turbo burner of an oil boiler. The device includes an air diffusing tube (5) encircling an oil spray nozzle (4) and functioning as both a first combustion tube and a stabilizer for whirling and diffusing a second combustion air as well as a first combustion air, and a second combustion tube (6) tightly fitted to the air diffusing tube (5). The air diffusing tube (5) comprises a cylindrical tube section, an engagement section integrally extending from the tube section such that it has a diameter smaller than that of the tube section (51), an air whirling sheet section (53) integrally extending from the engagement section (52) through a convex peripheral section (54). The engagement section is tightly inserted in the second combustion tube (6) to achieve a tight fit of the air diffusing tube (5) to the second combustion tube (6). The air whirling sheet section (53) is provided with a plurality of inclined radial slits (53a) for whirling the first combustion air. The convex peripheral section (54) has a plurality of second combustion air outlets (54a) for whirling the second combustion air.

Description

DEVICE FOR WHIRLING DIFFUSION OF COMBUSTION AIR FOR TURBO BURNER

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates in general to a device for supplying a combustion air for an oil burner of a boiler, and more particularly to a device for whirling supply of the combustion air in composite form to evenly mix the combustion air with oil sprayed by a spray nozzle and to provide a diffusion flame.

Description of the Prior Art There has been proposed a general type oil burner of a boiler which includes an air whirling diffusion sheet, or a circular stabilizer 3, disposed in a cylindrical blower tube 10 as shown in Figs. 1(A) and 1(B). In this general type of oil burner, simultaneously with whirling diffusion, a part of the combustion air inhaled into the blower tube 10 by the rotational force of a burner motor (not shown) is exhaled to the front of the stabilizer 3 through a plurality of air whirling slits 3a slantly εlitted on the circular stabilizer 3 disposed at the front of a spray nozzle 4 as shown in Fig. 3. The combustion air passing through the slits 3a is, so to speak, a first combustion air. At this time, the remaining combustion air, or a second combustion air, is exhaled from the blower tube 10 through a plurality of spaces 3c between the cylindrical blower tube 10 and the circular stabilizer 3 and blows in the same direction as that of the first combustion air while surrounding the diffusion flame to retain the shape of the flame. However, the second combustion air does not whirl but simply blows linearly while surrounding the diffusion flame, so that its velocity is so fast that it may cause an incomplete combustion.

In addition to the above general type of oil burner, a turbo type oil burner in which the combustion tube is divided into a first tube 1 and a second tube 2, and the stabilizer 3 is disposed in the first tube 1 has been proposed as disclosed in Korean Patent Appln. No. 92-11855, filed by this applicant, and shown in the accompanying drawings, Figs. 2(A) to 2(D). In this turbo type oil burner, the first combustion air is exhaled from the first tube 1 through a plurality of air whirling slits 3a of the stabilizer 3 disposed at the front of the spray nozzle 4 and whirls to be diffused to the position "A" inside the second tube 2 as shown in Fig. 4. At the same time, the second combustion air is exhaled from the first tube 1 to the second tube 2 through the spaces 3c between the first tube 1 and the stabilizer 3, and blows horizontally. In addition to the introduction of the first and second combustion air into the second tube 2, an incomplete combustion gas is introduced from the position "B" of the outside of the second tube 2 to the inside of the second tube 2 through a plurality of recombustion openings 2a of the second tube 2. In the turbo type oil burner, the combustion tube is divided into the two tubes 1 and 2 so as to intend to cause the incomplete combustion gas of the position "B" to be introduced to the inside of the second tube 2 through the recombustion openings 2a of the tube 2 heated to a temperature ranged from 750 hC to 1300 HC , and to be subjected to a recombustion, thereby achieving the desired complete combustion of the incomplete combustion gas of the outside of the diffusion flame. However, the second combustion air, inhaled to the inside of the second tube 2 through the spaces 3c between the first tube 1 and the stabilizer 3 to horizontally blow in the second tube 2, has the velocity so fast that the desired complete combustion is scarcely achieved.

Moreover, the first tube 1 of this turbo type burner is disposed at a position where the combustion air is continuously exhaled, so that the first tube 1 is not influenced by the diffusion flame. The first tube 1 is thus subjected to no thermal deformation and to .no oxidation corrosion such that it can be made of a cheap material, such as a general steel plate or a 27 stainless steel plate. However, the second tube 2 is disposed at the front of the oil spraying nozzle 4 to come into direct contact with the diffusion flame of high temperature, the flame conventionally having a temperature of about 750 h in the case of a small-sized burner, of about 1,100 C in the case of a middle-sized burner or of about 1,300 hC in the case of a large-sized burner. In this regard, the second tube 2 should be made of an expensive special alloy, such as a nickel-manganese alloy to resist the above high temperature of the diffusion flame, thus necessitating a capital investment.

SUMMARY OF THE INVENTION

It is, therefore, an object of the present invention to provide a device for whirling diffusion of a composite combustion air for a turbo burner in which the aforementioned problems can be overcome and which whirls the combustion air introduced into a second combustion tube and reduces the velocity of an incomplete combustion gas (flame) to make the incomplete combustion gas slowly impinge against all over the inner surface of the second tube heated to a high temperature, thereby retarding the combustion time to achieve the complete combustion and to improve the combustion efficiency.

It is another object of the present invention to provide a device for whirling diffusion of a combustion air for a turbo burner of which a second combustion tube is tightly fitted to a part of an air diffusing tube functioning as both a first combustion tube and a stabilizer, thereby facilitating the assembly and the disassembly of the combustion tube and saving the expensive material of the second combustion tube, and doubling the improvement of the combustion efficiency. To accomplish the above objects, a device for whirling diffusion of a combustion air for a burner in accordance with the present invention comprises an integral composite air diffusing tube encircling an oil spray nozzle and including a first combustion tube and a stabilizer as an integral member for whirling and diffusing a second combustion air as well as a first combustion air, and a second combustion tube tightly fitted to the composite air diffusing tube. In an embodiment of this invention, the air diffusing tube comprises a cylindrical tube section, an engagement section integrally extending from the tube section, an air whirling sheet section integrally extending from the engagement section through a convex peripheral section. The engagement section is tightly inserted in the second combustion tube to achieve the tight fit of the air diffusing tube to the second combustion tube. The air whirling sheet section is provided with a plurality of inclined radial slits for whirling the first combustion air. The convex peripheral section has a plurality of second combustion air outlets for whirling the second combustion air.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: Figs. 1(A) and 1(B) show an embodiment of a general type oil burner according to the prior art, in which:

Fig. 1(A) is a schematic sectional view of the oil burner; and

Fig. 1(B) is a sectional view of the oil burner taken along the section line A-A of Fig. 1(A);

Figs. 2(A) to 2(D) show an embodiment of a turbo type oil burner according to the prior art, in which: Fig. 2(A) is a schematic sectional view of the oil burner;

Fig. 2(B) is a sectional view of the oil burner taken along the section line B-B of Fig. 2(A); Fig. 2(C) is a side view of a first combustion tube of the oil burner; and

Fig. 2(D) is a side view of a second combustion tube of the oil burner to be brought into engagement with the first combustion tube; Fig. 3 is a sectional view showing a combustion air flow through a blower tube and a stabilizer of the general type oil burner of Fig. 1(A);

Fig. 4 is a sectional view showing a combustion air flow through first and second combustion tubes and a stabilizer of the turbo type oil burner of Fig. 2(A);

Figs. 5(A) to 5(C) show a turbo type oil burner in accordance with an embodiment of the present invention, in which:

Fig. 5(A) is a vertical sectional view of the oil burner;

Fig. 5(B) is a sectional view of the oil burner taken along the section line C-C of Fig. 5(A); and

Fig. 5(C) is an exploded side view of an air whirling diffusion device, comprising an air diffusing tube and a second combustion tube, prior to tight fitting of the tubes;

Figs. 6(A) and 6(B) show the air diffusing tube of the turbo type oil burner of Fig. 5(A), in which:

Fig. 6(A) is a perspective view of the air diffusing tube showing an embodiment wherein a plurality of air outlets are formed to incline leftwards; and

Fig. 6(B) is a sectional view of the air diffusing tube taken along the section line D-D of Fig. 6(A); and

Figs. 7. to 11 are perspective views of air diffusing tubes in accordance with other embodiments of the present invention, respectively; and

Fig. 12 is similar to Fig. 6 showing a plurality of air outlets which are formed to incline rightwards. DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to Figs. 5(A) to 5(C), there is shown a turbo type oil burner in accordance with an embodiment of the present invention. The turbo burner includes an air diffusing flanged tube 5 which is pressed into a flanged body. As best seen in Fig. 5(C), the flanged tube 5 has a cylindrical tube section 51 which integrally extends from the flange section and from which an engagement section 52 integrally extends while being stepped and reduced in its diameter. The air diffusing flanged tube 5 also has an air whirling sheet section 53 which extends from the engagement section 52 through a convex peripheral section 54 such that it is recessed on the distal end of the flanged tube 5. The air whirling sheet section 53 is slitted like the spokes of a wheel to provide a plurality of air whirling slits 3a. The engagement section 52 has a diameter smaller than that of the cylindrical tube section 51 and is tightly inserted into a second combustion tube 6 described later herein so as to achieve tight fit of the air diffusing tube 5 to the second combustion tube 6, thereby requiring no welding or no use of additional clamping means in engagement of the tube 5 with the second combustion tube 6.

The convex peripheral section 54, by way of which the air whirling sheet section 53 extends from the engagement section 52, is provided with a plurality of inclined air outlets 54a which are spaced apart from each other at regular intervals. The plurality of air outlets 54a are preferably provided by cutting and depressing the top surface of the convex peripheral section 54 such that each of the outlets 54a is inclined at an inclination angle. Thanking for the plurality of inclined air outlets 54a, the second combustion air introduced to the inside of the air diffusing tube 5 is exhaled from the tube 5 while whirling along a spiral passage about the central axis of the tube 5. Therefore, when the air outlets are formed to incline rightwards the exhaled air is supplied in rightward spirals while it is supplied in leftward spirals when the air outlets are formed to incline leftwards. Regardless of the direction of the air supply, the effects are equal. In accordance with other embodiments of the present invention, the plurality of air outlets 54a may be provided on other positions instead of the top surface of the convex peripheral section 54 or may not be inclined but vertically provided. For instance, Figs. 7 and 8 show embodiments in which the inclined air outlets 54a are provided on the inside surface of the convex peripheral section 54 and on the outside surface of the convex peripheral section 54, respectively. As shown in Fig. 9, a plurality of air outlets 54a may be vertically provided on the top surface of the convex peripheral section 54 such that the flow passage of the second combustion air is parallel with the central axis of the tube 5. The plurality of air outlets 54a may be also vertically provided on the inside surface of the convex peripheral section 54 as shown in Fig. 10, or on the outside surface of the convex peripheral section 54 as shown in Fig. 11.

The second combustion tube 6 tightly fitted to the air diffusing tube 5 has a cylindrical shape as shown in Figs. 5(A) and 5(C). In the second combustion tube 6, a plurality of recombustion openings 6a are provided at the lower section at which the tube 6 is fitted to the air diffusing tube 5. In the present invention, each of the recombustion openings 6a preferably has a circular or rectangular shape. The second combustion tube 6 is tightly inserted at its lower section on the engagement section 52 of the air diffusing tube 5 so as to achieve the desired tight fit thereof to the air diffusing tube 5, thus requiring no welding or no use of additional clamping means in engagement with the air diffusing tube 5. Moreover, such a tight fit of the second combustion tube 6 to the air diffusing tube 5 facilitates assembly and disassembly of the two tubes 5 and 6. In the present invention, the tight fit of the second combustion tube 6 to the air diffusing tube 5 is achieved by inserting the second tube 6 on the air diffusing tube 5 until it covers the engagement section 52 of the air diffusing tube 5- as shown in Fig. 5(A), thus desirably saving the expensive material of the second combustion tube 6. However, in the conventional turbo burner, the second combustion tube 2 should be inserted on all over the first combustion tube 1 until it comes into contact with the flange section la of the first tube 1 as shown in Fig. 4, thus requiring to have an additional length for reaching the flange section la and causing economical problem due to the additional length resulting in consumption of additional expensive material.

In accordance with the present invention, the turbo burner includes the air diffusing tube 5 which functions as both the conventional first combustion tube and the conventional stabilizer, thereby saving the expensive material of the second combustion tube, simplifying the assembling process and improving the performance of the burner. Otherwise stated, the air diffusing tube 5 of this invention completely overcomes the problem of assembling difficulty of the prior art introduced in precisely retaining the space between the first combustion tube and the stabilizer in the first combustion tube to cause a predetermined amount of combustion air to flow at a predetermined velocity, and improves the reliability of the burner.

The operational effect of the present invention will be described hereinbelow in comparison with the conventional turbo burner of Fig. 4. In operation of the conventional turbo burner, the oil sprayed from the nozzle 4 is mixed with the first combustion air, exhaled from the first combustion tube 1 through the stabilizer 3, to provide the fuel mixture which is burnt while whirling at the position "A" inside the second combustion tube 2. At the position "C" inside the second combustion tube 2, the incomplete combustion gas introduced from the position "B" to this position "C" through the recombustion openings 2a of the second tube 2 is subjected to the recombustion by the second combustion air horizontally supplied to the position "C" . That is, this conventional turbo burner intends to achieve the desired complete combustion by causing the incomplete combustion gas inhaled through the recombustion openings 2a as well as the flame formed at the front of the nozzle 4 to impinge against the inner surface of the second combustion tube 2 heated to a high temperature ranged from 750 he to 1,300 hC However, the desired complete combustion is scarcely achieved since the second combustion air rushes to the position "C" near the inner surface of the second combustion tube 2 at a high speed such that it expels the incomplete combustion gas prior to the recombustion and cools the inner surface of the second combustion tube 2. On the contrary, the second combustion air of the present invention, introduced into the position "C" of the second combustion tube 6, as well as the first combustion air whirls about the second tube 6 as shown in Fig. 5(A). Hence, the first combustion air and the second combustion air are supplied compositely while whirling.

That is, when the combustion air is inhaled into the air diffusing tube 5 functioning as both the first combustion tube as well as the stabilizer, a part of the combustion air is introduced as the first combustion air into the second combustion tube 6 through the air whirling slits 53a of the air whirling sheet section 53, and whirls and diffuses in the second tube 6. Simultaneously with whirling and diffusing, the second combustion air is mixed with the oil, sprayed from the nozzle 4, and burnt. The remaining part of the combustion air is introduced as the second combustion air into the second combustion tube 6 through the inclined air outlets 54a of the convex peripheral section 54. At this time, the second combustion air whirls to retain the desired flame shape and to sufficiently reduce the flow velocity of the incomplete combustion gas introduced into the second combustion tube through the recombustion opening 6a, and to cause the incomplete combustion gas to flow in whirls and vortex. The device for whirling diffusion of the combustion air of this invention thus allows the incomplete combustion gas to slowly flow in the second tube 6 while impinging against all over the inner surface of the second tube 6 heated to a high temperature ranged from 750 J5C to 1,300 he , thereby retarding the combustion time to achieve the desired recombustion of the incomplete combustion gas and to improve the combustion efficiency. As described above, the device for whirling diffusion of a combustion air of this invention uses an air diffusion tube functioning as both a first combustion tube and a stabilizer, thereby achieving the precise location of an air whirling sheet section functioning as the stabilizer. The air diffusing tube includes a plurality of air outlets on the convex peripheral section as well as a plurality of air whirling slits on the air whirling sheet section, thereby achieving the whirling diffusion of the second combustion air in the same manner as the first combustion air. The whirling diffusion of the second combustion air also achieves a lower air ratio as well as the desired high combustion efficiency. Furthermore, the second combustion tube is tightly inserted on the front section of the air diffusing tube to achieve the tight fit of the device of this invention, thus facilitating assembly and disassembly of the device and saving the expensive material of the second combustion tube.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

WHAT IS CLAIMED IS:

1. A device for whirling diffusion of a composite combustion air for a turbo burner comprising; an integral composite air diffusing tube encircling an oil spray nozzle and including a first combustion tube and a stabilizer as an integral member, said composite air diffusing tube whirling and diffusing a second combustion air as well as a first combustion air; and a second combustion tube tightly fitted to said composite air diffusing tube.

2. The device according to claim 1, wherein said air diffusing tube comprises: a cylindrical tube section; an engagement section integrally extending from said tube section such that it has a diameter smaller than that of said tube section, said engagement section being tightly inserted in said second combustion tube to achieve a tight fit of said air diffusing tube to said second combustion tube; and an air whirling sheet section integrally extending from said engagement section, said air whirling sheet section being provided with a plurality of radial slits each having an inclined side surface for whirling said first combustion air.

3. The device according to claim 2, wherein said air diffusing tube further comprises a convex peripheral section having a plurality of second combustion air outlets and integrally extending between said engagement section and said air whirling sheet section.

4. The device according to claim 3, wherein said second combustion air outlets are provided on a top surface of said convex peripheral section at regular intervals.

5. The device according to claim 3, wherein said second combustion air outlets are provided on an inside surface of said convex peripheral section at regular intervals.

6. The device according to claim 3, wherein said second combustion air outlets are provided on an outside surface of said convex peripheral section at regular intervals.

7. The device according to any one of claims 3 to 6, wherein each of said second combustion air outlets is inclined in its side surface.

8. The device according to any one of claims 3 to 6, wherein each of said second combustion air outlets is vertical in its side surface.

9. The device according to any one of claims 3 to 6, said second combustion air outlets are inclined leftwards at a predetermined angle.

10. The device according to any one of claims 3 to 6, said second combustion air outlets are inclined rightwards at a predetermined angle.