Fuel nozzle assembly including a pilot nozzle

Patent metadata

Field	Value
Publication number	US-2016305668-A1
Application number	US-201514688170-A
Country	US
Kind code	A1
Filing date	Apr 16, 2015
Priority date	Apr 16, 2015
Publication date	Oct 20, 2016
Grant date	—

Abstract

A fuel nozzle assembly includes a center body having a pilot air passage and a pilot fuel passage defined therein. A pilot nozzle having a plurality of premix passages is disposed within a downstream end portion of the center body. Each premix passage includes an inlet that is in fluid communication with the pilot air passage, an outlet that is positioned axially downstream from the inlet and a fuel port that is in fluid communication with the pilot fuel passage. An outer sleeve is coaxially aligned with and radially spaced from the center body so as to define an annular passage therebetween. A strut extends radially outwardly from the center body to the outer sleeve. The fuel nozzle assembly further includes an inlet passage that is in fluid communication with the pilot air passage. The inlet passage extends through the outer sleeve, the strut and the center body.

First claim

What is claimed:

1 . A fuel nozzle assembly, comprising:
a center body that extends axially along a centerline of the fuel nozzle assembly, the center body having a pilot air passage and a pilot fuel passage defined therein; a pilot nozzle disposed within a downstream end portion of the center body, the pilot nozzle having a plurality of premix passages, each premix passage having an inlet in fluid communication with the pilot air passage, an outlet downstream from the inlet and a fuel port in fluid communication with the pilot fuel passage; an outer sleeve coaxially aligned with and radially spaced from the center body so as to define an annular passage therebetween; a strut that extends radially outwardly from the center body to the outer sleeve; and an inlet passage in fluid communication with the pilot air passage, wherein the inlet passage extends through the outer sleeve, the strut and the center body.

2 . The fuel nozzle assembly as in claim 1 , wherein an outer wall of the pilot nozzle is slideably engaged with an inner surface of the center body.

3 . The fuel nozzle assembly as in claim 1 , wherein the strut is a swirler vane.

4 . The fuel nozzle assembly as in claim 1 , wherein the plurality of premix passages is annularly arranged about an axial centerline of the fuel nozzle assembly between an inner wall and an outer wall of the pilot nozzle.

5 . The fuel nozzle assembly as in claim 1 , wherein the pilot air passage is defined between an intermediate tube that extends coaxially within the center body and an inner surface of the center body.

6 . The fuel nozzle assembly as in claim 4 , wherein a downstream end of the intermediate tube is sealed to an upstream portion of the pilot nozzle radially inward from the inlets of the premix passages.

7 . The fuel nozzle assembly as in claim 1 , wherein the pilot fuel passage is defined between an inner tube and an intermediate tube, wherein the inner tube and the intermediate tube extend coaxially within the center body.

8 . The fuel nozzle assembly as in claim 1 , wherein a portion the pilot fuel passage is at least partially defined between an outer surface of an inner tube and an inner wall of the pilot nozzle.

9 . The fuel nozzle assembly as in claim 8 , wherein the inner tube extends at least partially through the pilot nozzle.

10 . A combustor for a gas turbine, the combustor comprising:
an end cover coupled to an outer casing, wherein the end cover and the outer casing form a head end portion of the combustor, wherein the head end is in fluid communication with a compressor of the gas turbine; and a fuel nozzle assembly connected to the end cover and extending axially within the head end portion of the combustor, the fuel nozzle comprising:
a center body that extends axially along a centerline of the fuel nozzle assembly, the center body having a pilot air passage and a pilot fuel passage defined therein;
a pilot nozzle disposed within a downstream end portion of the center body, the pilot nozzle having a plurality of premix passages, each premix passage having an inlet in fluid communication with the pilot air passage, an outlet downstream from the inlet and a fuel port in fluid communication with the pilot fuel passage;
an outer sleeve coaxially aligned with and radially spaced from the center body so as to define an annular passage therebetween;
a strut that extends radially outwardly from the center body to the outer sleeve; and
an inlet passage in fluid communication with the pilot air passage and the head end portion of the combustor, wherein the inlet passage extends through the outer sleeve, the strut and the center body.

11 . The combustor as in claim 10 , wherein an outer wall of the pilot nozzle is slideably engaged with an inner surface of the center body.

12 . The combustor as in claim 10 , wherein the strut is a swirler vane.

13 . The combustor as in claim 10 , wherein the plurality of premix passages is annularly arranged about an axial centerline of the fuel nozzle assembly between an inner wall and an outer wall of the pilot nozzle.

14 . The combustor as in claim 10 , wherein the pilot air passage is defined between an intermediate tube that extends coaxially within the center body and an inner surface of the center body.

15 . The combustor as in claim 14 , wherein a downstream end of the intermediate tube is sealed to an upstream portion of the pilot nozzle radially inward from the inlets of the premix passages.

16 . The combustor as in claim 10 , wherein the pilot fuel passage is defined between an inner tube and an intermediate tube, wherein the inner tube and the intermediate tube extend coaxially within the center body.

17 . The combustor as in claim 10 , wherein a portion the pilot fuel passage is at least partially defined between an outer surface of an inner tube and an inner wall of the pilot nozzle.

18 . The combustor as in claim 17 , wherein the inner tube extends at least partially through the pilot nozzle.

19 . A fuel nozzle assembly, comprising:
a center body that extends axially along a centerline of the fuel nozzle assembly, the center body having an annular pilot air passage and an annular pilot fuel passage defined therein, wherein the pilot air passage is defined radially outwardly from the pilot fuel passage, wherein the fuel nozzle assembly further includes a base portion that is in fluid communication with the pilot air passage, wherein the base portion is configured to receive pilot air from an end cover of a combustor; and a pilot nozzle disposed within a downstream end portion of the center body, the pilot nozzle having a plurality of premix passages, each premix passage having an inlet in fluid communication with the pilot air passage, an outlet downstream from the inlet and a fuel port in fluid communication with the pilot fuel passage.

20 . The fuel nozzle assembly as in claim 19 , wherein the plurality of premix passages is annularly arranged about an axial centerline of the fuel nozzle assembly between an inner wall and an outer wall of the pilot nozzle.

21 . The fuel nozzle assembly as in claim 19 , wherein the pilot air passage is defined between an intermediate tube and an inner surface of the center body, wherein the intermediate tube extends coaxially within the center body from the base portion to the pilot nozzle.

22 . The fuel nozzle assembly as in claim 21 , wherein a downstream end of the intermediate tube is sealed to an upstream portion of the pilot nozzle radially inwardly from the inlets of the premix passages.

23 . The fuel nozzle assembly as in claim 21 , further comprising an expansion member, wherein a downstream end of the intermediate tube is coupled to an upstream portion of the pilot nozzle via the expansion member radially inwardly from the inlets of the premix passages.

24 . The fuel nozzle assembly as in claim 19 , wherein the pilot fuel passage is defined between an inner tube and an intermediate tube, wherein the inner tube and the intermediate tube extend coaxially within the center body from the base portion to the pilot nozzle.

25 . The fuel nozzle assembly as in claim 19 , wherein a portion of the pilot fuel passage is at least partially defined between an outer surface of an inner tube and an inner wall of the pilot nozzle.

26 . The fuel nozzle assembly as in claim 25 , wherein the inner tube extends at

Assignees

• Gen Electric

Inventors

• Romig Bryan Wesley
• Ouellet Dereck Joseph
• Stewart Jason Thurman
• Gibson Michael Christopher

Classifications

• F23R2900/03343

  Pilot burners operating in premixed mode · CPC title

• F23R3/286 Primary

  having fuel-air premixing devices (F23R3/30 takes precedence) · CPC title

• F23R3/14

  by using swirl vanes · CPC title

• F23R3/343 Primary

  Pilot flames, i.e. fuel nozzles or injectors using only a very small proportion of the total fuel to insure continuous combustion (ignition in gas-turbine plants F02C7/264; pilot flame igniters F23Q9/00) · CPC title