Premixing burner

• US 5,586,878 A
• Filed: 11/02/1995
• Issued: 12/24/1996
• Est. Priority Date: 11/12/1994
• Status: Expired due to Term

• Current Assignee: Alstom SA
• Original Assignee: ABB Research Ltd. (ABB Ltd.)
• Inventors: Santner, Johannes, Steinbach, Christian, Dobbeling, Klaus
• Primary Examiner(s): Yeung, James C.
• Application Number:
  US08/552,088
• Time in Patent Office: 418 Days
• Field of Search: 431/350, 431/351, 431/284, 431/353, 431/354, 431/8, 431/10, 431/173, 431/187, 60/464, 60/743
• US Class Current: 431/351
• 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: F23C 7/002 the air being submitted to a rotary or spinning motion cyclonic combustion chamber F23C3/006
• CPC Class Codes: F23D 11/38 Nozzles; Cleaning devices therefor
• CPC Class Codes: F23D 11/402 Mixing chambers downstream of the nozzle
• CPC Class Codes: F23D 17/002 gaseous or liquid fuel

Abstract

In a premixing burner of the double-cone design for operating an internal combustion engine, a combustion chamber of a gas-turbine group, or a firing plant, having a high-pressure atomization nozzle (3), arranged at the cone apex, for atomizing liquid fuel, which high-pressure atomization nozzle (3) consists of a nozzle body in which at least one feed passage (24) is arranged for the liquid fuel (12) to be atomized, which can be fed at a pressure greater than 100 bar, and this feed passage (24), with or without a turbulence chamber (25) arranged in between, is connected via at least two nozzle bores (18) to the interior space (14) of the burner, the nozzle bores (18) are aligned with the zones of high air velocity in the burner, and the angle (β) between the fuel-droplet spray (4) and the longitudinal axis (5) of the burner is at least as large as the cone half angle (β) between the sectional cone bodies (1, 2) and the longitudinal axis (5) of the burner. Fine atomization is thereby combined with a high fuel impulse, which is the precondition for quick vaporization of the fuel as well as for good premixing.

Claims

1. A premixing burner of the double-cone design for operating an internal combustion engine, a combustion chamber of a gas-turbine group, or a firing plant, the burner comprising:

at least two hollow conical sectional bodies positioned to enclose a conical interior space that widens in a direction of flow at a cone half angle which is constant in the direction of flow, longitudinal symmetry axes of the sectional bodies being parallel to a longitudinal axis of the burner and mutually offset to define opposed tangential flow air-inlet slots on opposite sides of the interior space for a combustion-air flow,

a nozzle for atomizing a liquid fuel arranged in a narrowest cross section of the conical interior space, the nozzle being directed for fuel injection at an acute angle to the longitudinal axis of the burner,

wherein the nozzle is a high-pressure atomization nozzle comprising a nozzle body having at least one feed passage for delivering liquid fuel to be atomized at a pressure greater than 100 bar, and at least two nozzle bores to spray fuel droplets into the interior space of the burner, wherein the nozzle bores are aligned with zones of high air velocity in the burner interior space, and the acute angle between the fuel-droplet spray and the longitudinal axis of the burner is at least as large as the cone half angle between the sectional cone bodies and the longitudinal axis of the burner.

2. The premixing burner as claimed in claim 1, wherein the nozzle bores of the high-pressure atomization nozzle are aligned with the air-inlet slots of the conical sectional bodies.

3. The premixing burner as claimed in claim 1, wherein the high-pressure atomization nozzle is a turbulence-assisted high-pressure nozzle having a turbulence chamber defined by a tube and a conical cap closing an outlet end of the tube, wherein the nozzle bores are positioned in the conical cap, and a filling piece having at least one feed opening separates the turbulence chamber from the at least one feed passage.

4. The premixing burner as claimed in claim 3, wherein the nozzle bores are arranged in a radially outer third of the conical cap close to a wall of the tube.

5. The premixing burner as claimed in claim 3, wherein the feed opening is arranged centrally in the filling piece.

6. The premixing burner as claimed in claim 1, wherein the high-pressure atomization nozzle is a high-pressure orifice nozzle which consists of a tube having a conical cap on an outlet end of the tube, and the nozzle openings are arranged in the conical cap.

7. The premixing burner as claimed in claim 6, wherein the nozzle bores are arranged in a radially outer third of the conical cap close to a wall of the tube.

8. The premixing burner as claimed in claim 1, further comprising means for introducing additional fuel in the tangential flow air inlet slots.