Burner for premixing combustion of a liquid and/or gaseous fuel

• US 5,244,380 A
• Filed: 03/02/1992
• Issued: 09/14/1993
• Est. Priority Date: 03/12/1991
• Status: Expired due to Term

• Current Assignee: Alstom SA
• Original Assignee: Asea Brown Boveri Ltd (ABB Limited)
• Inventors: Sattelmayer, Thomas, Dobbeling, Klaus
• Primary Examiner(s): Yeung, James C.
• Application Number:
  US07/844,169
• Time in Patent Office: 561 Days
• Field of Search: 431/2, 431/8, 431/173, 431/10, 431/116, 431/284, 431/354, 431/182, 431/285, 431/350, 60/737, 60/748, 239/290, 239/399, 239/403, 110/264, 110/347
• US Class Current: 431/8
• CPC Class Codes: F23C 2900/07002 Premix burners with air inlet slots obtained between offset curved wall surfaces, e.g. double cone burners
• CPC Class Codes: F23D 11/402 Mixing chambers downstream of the nozzle
• CPC Class Codes: F23D 17/002 gaseous or liquid fuel
• CPC Class Codes: F23R 3/12 inducing a vortex
• CPC Class Codes: F23R 3/286 having fuel-air premixing devices F23R3/30 takes precedence
• CPC Class Codes: F23R 3/30 comprising fuel prevapourising devices

Abstract

In a burner for premixing-type combustion of a liquid and/or gaseous fuel, which essentially comprises hollow conical part-bodies (1, 2) positioned one upon the other, the center lines of which extend mutually offset in the longitudinal direction, whereupon tangential inlet openings (1b, 2b) are formed on both sides of the burner, a fuel (5a) is admixed to the combustion air (13) flowing into the interior (3) of the burner in that area. This admixture is accomplished via a number of nozzles (9, 10), which act in the region of the inlet openings (1b, 2b). The fuel through these nozzles is injected with a small spray cone angle in the longitudinal direction of the slot. The fuel vaporization takes place essentially only in the inlet openings of the burner, with the result that only a fuel vapor enters the interior (3). A further central nozzle (4) supplied with a liquid and/or gaseous fuel provides assistance in the form of a limit fuel quantity. The ignition of the mixture (4a, 5a, 13) takes place at the outlet of the burner, stabilization of the flame front (14) being brought about in the region of the burner aperture by a return flow zone (15).

Claims

1. A burner for premixed combustion of one of a liquid and gaseous fuel, comprising:

two hollow conical part-bodies, each body having a longitudinal centerline;

the hollow conical part-bodies positioned adjacent one another, the respective center lines parallel and mutually offset so to form a burner body having a substantially conical interior space, a start and an outlet end, and two longitudinally extending inlet openings for tangential inflow of a combustion air stream into the interior of the burner; and

,

at least one nozzle arranged in the region of each inlet opening for injecting a fuel in the longitudinal direction of the inlet openings, essentially transversely to a tangentially inflowing combustion air stream into the interior of the burner.

2. The burner as claimed in claim 1, further comprising a plurality of nozzles arranged in the region of each inlet opening, wherein nozzles placed at each end of the inlet openings are each directed to inject towards the other end of the inlet opening, and at least one pair of nozzles placed between the ends of the inlet openings are directed to inject in mutually opposing directions toward the ends of the inlet openings.

3. The burner as claimed in claim 1, wherein the spray direction of the nozzles is inclined toward the longitudinal axis of the burner.

4. The burner as claimed in claim 1, wherein the nozzles are connected for fuel flow to central feed conduits, which extend along the burner body upstream of the inlet openings.

5. The burner as claimed in claim 1, wherein, in the direction of flow, the conical inclination of the part-bodies is at a fixed angle.

6. The burner as claimed in claim 1, further comprising a further nozzle placed in the burner interior at the start of the burner for injection of one of a liquid and gaseous fuel into the interior of the burner.

7. The burner as claimed in claim 1, wherein the part-bodies include a collar-shaped plate at the outlet end substantially perpendicular to the axis of the conical part-body, said plate having a number of openings.

8. The burner as claimed in claim 1, wherein the part-bodies have a progressive cone inclination in the direction of flow.

9. The burner as claimed in claim 1, wherein the part-bodies have a degressive cone inclination in the direction of flow.

10. A method for operating a burner of the type comprising:

two hollow conical part-bodies, each body having a longitudinal centerline;

the hollow conical part-bodies positioned adjacent one another, the respective center lines parallel and mutually offset so to form a burner body having a substantially conical interior space, a start and an outlet end, and two longitudinally extending inlet openings for tangential inflow of a combustion air stream into the interior of the burner;

at least one nozzle arranged in the region of each inlet opening for injecting a fuel in the longitudinal direction of the inlet openings, essentially transversely to the tangentially inflowing combustion air stream, into the interior of the burner; and

,

a further nozzle in the interior of the burner at the start,

the method comprising;

injecting a fuel with a small spray cone angle in the longitudinal direction of the inlet opening;

allowing an inflowing combustion air stream through the inlets openings to vaporize the fuel essentially only in the inlet openings, wherein only a fuel vapor flows into the interior of the burner;

injecting, through the further nozzle at the start of the burner, one of a liquid and gaseous fuel up to a limit fuel quantity; and

,

igniting the mixture, wherein ignition takes place at the outlet of the burner, a stabilization of a flame front being brought about in the region of the burner outlet by a return flow zone.

11. A burner for premixed combustion of a fuel, comprising:

two hollow, conical part-bodies, each body having a longitudinal centerline;

the hollow conical part-bodies positioned adjacent one another, their respective center lines parallel and mutually offset so to form a burner body having a substantially conical, hollow interior space, and two longitudinally extending inlet openings for tangential inflow of a combustion air stream into the interior of the burner; and

,

at least one nozzle for injecting a fuel arranged in each inlet opening, the nozzles being positioned to inject fuel into the inlet openings in the longitudinal direction of the inlet openings and essentially transversely to a tangentially inflowing combustion air stream, so that fuel injected into the inlet openings is vaporized by the inflowing air stream and a resulting air/fuel mixture flows into the burner body.

12. The burner as claimed in claim 11, wherein nozzles are provided at each end of the inlet openings and are each directed to inject towards the other end of the inlet opening, and at least one pair of nozzles is placed between the ends of the inlet openings and directed to inject in mutually opposing directions toward the ends of the inlet openings.

13. The burner as claimed in claim 11, wherein the nozzles are directed to inject oblique to the inlet openings and toward the interior of the burner.