← Back to Patent Explorer
US5408830A Expired / Lapsed US ⏱️ 0.0 years remaining

Multi-stage fuel nozzle for reducing combustion instabilities in low NOX gas turbines

Assignee: General Electric Co
•
Filing: 1994-02-10
•
Granted: 1995-04-25
•
Expires: 2014-02-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A fuel nozzle for gas turbine combustors reduces combustion instabilities by injecting purge air into the combustor angularly instead of axially. The fuel nozzle has a substantially cylindrical body with a number of internal passages. One of the passages provides premix gas fuel to a plurality of fuel injectors attached to the fuel nozzle. The remaining passages can be for diffusion gas, atomizing air and liquid fuel. One or more of the remaining passages is connected to a respective group of discharge orifices formed in the cylindrical side surface of the nozzle body. During low NO x operation, premix gas is introduced through the fuel injectors, and the remaining passages are all purged with air to prevent the ingress of flame gases from the combustion chamber. The resulting jets of air emitted from discharge orifices formed in the side surface will disrupt or break-up spanwise vortices shed from the bluff end of the fuel nozzle, thereby reducing combustion instabilities. These air jets are preferably discharged at an angle of about 45 degrees to the longitudinal axis of the fuel nozzle. The orifices can be rectangular, circular or triangular in shape.

Inventors

  • 👤 Jeffery A. Lovett

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 11:46
CPC Classifications
F; F23; F23R; F23R3/00; F23R3/28; F23R3/36; F23D; F23D17/00; F23D17/002; F23R3/286; F23D2209/00; F23D2209/30; F23D2210/00; F23R2900/00; F23R2900/00014

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 95 words
A fuel nozzle assembly comprising: a substantially cylindrical body having a cylindrical surface, a longitudinal axis and first and second internal passages; a plurality of fuel injectors extending radially outward from the cylindrical surface of said body, each one of said fuel injectors having at least one injection port in fluid communication with said first passage; a plurality of discharge orifices formed in the cylindrical surface of said body; and a plurality of channels fluidly connecting said discharge orifices to said second passage, each of said channels forming an acute angle with said longitudinal axis.
Claim 2
Dependent Claim 95 words
A fuel nozzle assembly comprising: a substantially cylindrical body having a cylindrical surface, a longitudinal axis and first and second internal passages; a plurality of fuel injectors extending radially outward from the cylindrical surface of said body, each one of said fuel injectors having at least one injection port in fluid communication with said first passage; a plurality of discharge orifices formed in the cylindrical surface of said body; and a plurality of channels fluidly connecting said discharge orifices to said second passage, each of said channels forming an acute angle with said longitudinal axis.
Claim 3
Dependent Claim 13 words
The fuel nozzle of claim 1 wherein said angle is approximately 45 degrees.
Claim 4
Dependent Claim 50 words
The fuel nozzle of claim 1 wherein said body comprises a plurality of concentric tubes and a discharge tip disposed at the forward end of said tubes, said first and second passages being formed between adjacent ones of said tubes and said discharge orifices being formed in said discharge tip.
Claim 5
Dependent Claim 17 words
The fuel nozzle of claim 3 wherein said plurality of channels are formed in said discharge tip.
Claim 6
Dependent Claim 43 words
The fuel nozzle of claim 1 further comprising a third passage in said body and a second plurality of discharge orifices formed in the cylindrical surface of said body, said second plurality of discharge orifices being in fluid communication with said third passage.
Claim 7
Dependent Claim 15 words
The fuel nozzle of claim 1 wherein each one of said discharge orifices is rectangular.
Claim 8
Dependent Claim 15 words
The fuel nozzle of claim 1 wherein each one of said discharge orifices is circular.
Claim 9
Dependent Claim 15 words
The fuel nozzle of claim 1 wherein each one of said discharge orifices is triangular.
Claim 10
Dependent Claim 113 words
A gas turbine apparatus comprising at least one fuel nozzle assembly, said fuel nozzle assembly comprising: a substantially cylindrical body having a cylindrical surface, a longitudinal axis, a premix gas passage and a diffusion gas passage disposed therein; a plurality of fuel injectors extending radially outward from the cylindrical surface of said body, each one of said fuel injectors having at least one injection port in fluid communication with said premix gas passage; a plurality of discharge orifices formed in the cylindrical surface of said body; and a plurality of channels fluidly connecting said discharge orifices to said diffusion gas passage, each of said channels forming an acute angle with said longitudinal axis.
Claim 11
Dependent Claim 113 words
A gas turbine apparatus comprising at least one fuel nozzle assembly, said fuel nozzle assembly comprising: a substantially cylindrical body having a cylindrical surface, a longitudinal axis, a premix gas passage and a diffusion gas passage disposed therein; a plurality of fuel injectors extending radially outward from the cylindrical surface of said body, each one of said fuel injectors having at least one injection port in fluid communication with said premix gas passage; a plurality of discharge orifices formed in the cylindrical surface of said body; and a plurality of channels fluidly connecting said discharge orifices to said diffusion gas passage, each of said channels forming an acute angle with said longitudinal axis.
Claim 12
Dependent Claim 53 words
The gas turbine apparatus of claim 9 wherein said body comprises a plurality of concentric tubes and a discharge tip disposed at the forward end of said tubes, said premix gas and diffusion gas passages being formed between adjacent ones of said tubes and said discharge orifices being formed in said discharge tip.
Claim 13
Dependent Claim 18 words
The gas turbine apparatus of claim 9 wherein said plurality of channels are formed in said discharge tip.
Claim 14
Dependent Claim 14 words
The gas turbine apparatus of claim 9 wherein said angle is approximately 45 degrees.
Claim 15
Dependent Claim 82 words
The gas turbine apparatus of claim 9 further comprising: a liquid fuel passage in said body; a second plurality of discharge orifices formed in the cylindrical surface of said body, said second plurality of discharge orifices being in fluid communication with said liquid fuel passage; an atomizing air passage in said body; and a third plurality of discharge orifices formed in the cylindrical surface of said body, said third plurality of discharge orifices being in fluid communication with said atomizing air passage.
Claim 16
Dependent Claim 16 words
The gas turbine apparatus of claim 9 wherein each one of said discharge orifices is rectangular.
Claim 17
Dependent Claim 16 words
The gas turbine apparatus of claim 9 wherein each one of said discharge orifices is circular.
Claim 18
Dependent Claim 16 words
The gas turbine apparatus of claim 9 wherein each one of said discharge orifices is triangular.
Claim 19
Dependent Claim 18 words
The gas turbine apparatus of claim 9 wherein said discharge orifices are located downstream from said fuel injectors.
Claim 20
Dependent Claim 18 words
The gas turbine apparatus of claim 1 wherein each of said channels is angled in a circumferential direction.
Claim 21
Dependent Claim 18 words
The gas turbine apparatus of claim 9 wherein each of said channels is angled in a circumferential direction.

References Cited (Backward Citations)

US1494020A Cited
US4311277A Cited
US4373325A Cited
US4589260A Cited
US4982570A Cited
US5193346A Cited
US4850194A Cited
US4833878A Cited
US5199265A Cited
US5259184A Cited
US5218824A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-04-24 1998-10-24 1999-04-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-04-24 2002-10-24 2003-04-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-04-24 2006-10-24 2007-04-25 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag