EP0054542A1

EP0054542A1 - Oil burner nozzle

Info

Publication number: EP0054542A1
Application number: EP19800901446
Authority: EP
Inventors: Donald G. Wright
Original assignee: ADELPHI RESEARCH CENTER Inc
Current assignee: ADELPHI RESEARCH CENTER Inc
Priority date: 1980-06-27
Filing date: 1980-06-27
Publication date: 1982-06-30
Also published as: WO1982000106A1; AU6127580A

Abstract

Ajutage de bruleur a petrole (1) utilise avec des combustibles liquides et des combustibles liquides contenant des solides. L'ajutage comprend un tube porteur du combustible (6), un cylindre (8) dispose concentriquement autour du tube (6), et un manchon externe (10) retenant un organe pour le cylindre (8). Une vapeur d'atomisation passe le long d'un passage axial dans le cylindre (8), au travers d'un alesage (18) du cylindre (8) puis le long de la surface externe de la partie anterieure (14) du cylindre (8). La vapeur d'atomisation est dirigee par le manchon externe (10) en travers du passage du combustible lorsqu'il emerge du cylindre (8). Le combustible est atomise puis peut etre allume.Oil burner nozzle (1) used with liquid fuels and liquid fuels containing solids. The nozzle comprises a fuel carrier tube (6), a cylinder (8) arranged concentrically around the tube (6), and an outer sleeve (10) retaining a member for the cylinder (8). Atomizing vapor passes along an axial passage in the cylinder (8), through a bore (18) of the cylinder (8) and then along the external surface of the front part (14) of the cylinder (8). The atomizing vapor is directed by the external sleeve (10) across the passage of the fuel as it emerges from the cylinder (8). The fuel is atomized and can then be ignited.

Description

OIL BURNER NOZZLE Background of the Invention This invention relates to an oil burner nozzle. More particularly, this invention relates to an oil burner nozzle which increases the efficiency of combustion of liquid and solid-containing liquid fuels by atomizing such fuels. With the increased public concern about the cost and the availability oil, it has become desirable to design oil burners and, more particularly, oil burner nozzles, that are more efficient than the ones currently in use. Atom ization is a well-known process for increasing the efficiency of combustion. However, conventional oil burner nozzles which atomize these fuels are not de signed to operate at low rates of fuel flow.

Because solid combustibles, such as coal, are more abundant than oil, another desirable goal is to design an oil burner nozzle which can utilize solid-containing liquid fuels as well as purely liquid fuels. In prior art devices, such as that described in U.S. Pat. No. 733,579, the fuel must pass through constricted passageways. These passageways would tend to clog in the presence of solids. While some devices, such as those described in U.S. Pat. Nos. 2,933,259 and 2,929,290, are described as capable of atomizing solid- containing liquid fuels, it is obvious that the solid matter would have to be highly pulverized in order to prevent clogging. Moreover, these latter two devices are complicated and require careful machining.

Thus, there is a need for a simple and inexpensive oil burner nozzle, capable of operating at low rates of fuel flow, and capable of atomizing solidcontaining liquid fuels as well as liquid fuels. This invention is directed to providing a device meeting such needs.

Summary of the Invention The present invention provides an oil burner nozzle comprising a pipe for carrying fuel, a barrel disposed about the pipe, and an outer sleeve disposed about the barrel. The pipe transports the fuel through the barrel to an outlet. The barrel has a main body and a smaller front portion, an axial pass ageway which carries an atomizing vapor from the main body to the front portion of the barrel, and a lateral bore which conducts the atomizing vapor from the axial passageway to the outer surface of the front portion of the barrel. The outer sleeve forms a converging chamber about the front portion of the barrel and directs the atomizing vapor across the path of the fuel emerging from the barrel.

In a preferred embodiment, the barrel and outer sleeve are cylindrical and are concentrically disposed about the fuel pipe which passes through the axial passageway. The exit orifice of the outer sleeve abuts against the front portion of the barrel and the front portion has grooves scored into its outer surface at an angle oblique to the axis of the barrel.

Brief Description of the Drawings

The accompanying drawings show a preferred embodiment of the present invention.

Fig. 1 is a longitudinal sectional view of the device.

Fig. 2 is a cross-sectional view of the device taken along line 2-2 of Fig. 1.

Fig. 3 is a cross-sectional view of the device taken along line 3-3 of Fig. 1.

Detailed Description

Referring to the specific embodiment illustrated in the accompanying drawings, the oil burner nozzle of the present invention, generally indicated as 1, has a fuel entry end 2 and a fuel exit end 4. The nozzle shown comprises fuel carrying pipe 6, barrel 8 concentrically disposed about pipe 6, and outer sleeve 10 concentrically disposed about barrel 8. As shown, both barrel 8 and outer sleeve 10 are cylindrical in shape. Barrel 8 has a central borehole 18 formed with an inner surface 16 in the main body 12. The diameter of central borehold 18 is sufficiently larger than the outer diameter of fuel carrying pipe 6 so that an axial passageway to admit atomizing vapor is formed between the outer surface of pipe 6 and the inner surface 16 of barrel 8. Borehole 18 has a narrow segment 22 formed by inner surface 24 which closely receives fuel pipe 6 within front portion 14. Borehold 18 terminates as outlet 26 which functions as exit end 4 of the nozzle. A second pipe 28 concentrically disposed about fuel pipe 6 and dimensioned to be received within the wide segment of borehole 18 may be used to introduce the atomizing vapor within the borehole

Front portion 14 of barrel 8 is formed with a face 30 beveled in the direction of the fuel exit end 4 of the burner nozzle 1. At least one and preferably a plurality of grooves 32 are scored preferably symmetrically into face 30 at an angle oblique to the axis of the barrel 8. Lateral bores 34 communicate the atomizing vapor from the wide segment of borehold 18 to the outside surface 25 of the front portion 14.

Outer sleeve 10 is a hollow member having a sloped front end 36 and a central exit orifice 38. The inner edge 40 of exit orifice 38 abuts beveled face 30 of the barrel near outlet 26. As shown, outer sleeve 10 is dimensioned to engage slidably the main body 12 of barrel 8 but to leave a gap between the inner surface 42 of the outer sleeve and the outer surface 25 of front portion 14. As both barrel 8 and outer sleeve are cylindrical and as their front faces intersect each other, the gap forms an annular chamber 44 converging upon exit orifice 38. When atomizing bapor under pressure enters annular chamber 44, in ner surface 42 acts as a deflecting plate, directing the atomizing towards exit orifice 38. Set screws 46 are placed in outer sleeve 10 in order to keep outer sleeve 10 in spatial alignment with barrel 8.

In operation, fuel passes through barrel 8 via fuel pipe 6 and borehole 18, emerging at outlet 26. The atomizing vapor is introduced under slight pres sure, for example, at 7 to 12 p.s.i.g., into the wide segment of borehole 18 by pipe 28. The narrowness of segment 22 of the borehold prevents the atomizing vapor from traveling the length of barrel 8. From borehole 18 the atomizing vapor is forced through lateral bores 34 into annular chamber 44. Inner surface 42 deflects the path of the atomizing vapor along outer surface 25 and beveled face 30 of the front portion 14. As edge 40 of orifice 38 abuts against beveled face 30, the only avenues of escape for the atomizing are through grooves 32. The vapor issues from annular chamber 44 through grooves 32 in a swirling motion, shearing across the path of the fuel emerging from outlet 26. The fuel is thereby atomized and may be ignited for efficient combustion.

The angle of inclination of beveled face 30 can be varied to control the size of the flame. Preferably, the angle should be from 20° to 45° from horizontal.

The atomizing vapor may be air, steam or any other conventional gas used for such purposes. The nozzle is suitable for use with purely liquid fuels and with liquid fuels containing up to 50% or more solid particles. These particles may range from 1 to 100 microns or more in diameter. In actual operation, the following fuels have been used successfully: Nos. 2, 4, 5 and 6 heating oils; coal and oil mixtures with concentrations up to 50% coal; wood oil; mixtures of coal/water/oil, coal/wood oil, wood oil/oil, wood oil/water/oil, wood particles/wood oil, wood particles/oil, wood particles/coal/oil, and other combinations thereof.

The nozzle of the present invention is highly efficient at both low and high fuel flow rates. For example, the nozzle has been successfully used atflow rates as low as one-half gallon per hour, a flow rate suitable for smallscale., residential oil burners. Alternatively, larger nozzles capable of handling as much as two thousand gallons of fuel per hour may be constructed. A battery of such nozzles may be used to burn the ten to twenty-five thousand gallons of fuel per hour needed to heat large-scale apartment houses. While the present invention has been described with reference to a specific embodiment, it should be understood that numerous changes in the details of construction may be made without departing from the spirit and scope of the invention.

Claims

WHAT IS CLAIMED IS:

1. A burner nozzle, comprising:

(a) a barrel having amain body portion, a front portion smaller than the main body portion, and an inner surface forming a bore hole for carrying atomizing vapor from the main body portion to the front portion of said barrel and at least one bore communi cating the atomizing vapor from the borehold to the outside surface of the front portion of said barrel;

(b) means for carrying a fuel disposed within said barrel, said fuel- carrying means having an outlet to discharge fuel from the front portion of said barrel; and

(c) an outer sleeve adapted to receive closely the main body portion of said barrel, said outer sleeve having an exit orifice near the outlet of said barrel, said outer sleeve forming a converging chamber about the front portion of said barrel to discharge the atomizing vapor across the path of the fuel as it emerges from said barrel.

2. A burner nozzle as claimed in claim 1, wherein said fuel-carrying means is a pipe concentrically disposed within the borehole and the borehole is adapted to receive closely said pipe in the front portion of said barrel.

3. A burner nozzle as claimed in Claim 2 wherein said barrel and said outer sleeve have a cylindrical shape.

4. A burner nozzle as claimed in Claim 3 wherein the front portion of said barrel has a beveled outer face.

5. A burner nozzle as claimed in Claim 4 wherein the beveled face of barrel has a groove extending to the fuel outlet.

6. A burner nozzle as claimed in Claim 5 wherein the groove is at an angle oblique to the axis of the barrel.

7. A burner nozzle as claimed in Claim 6 wherein the exit orifice from said outer sleeve abuts against the front portion of said barrel near the fuel outlet.