Air swirler arrangement for a fuel injector of a combustion chamber

Patent metadata

Field	Value
Publication number	US-11085643-B2
Application number	US-201916254705-A
Country	US
Kind code	B2
Filing date	Jan 23, 2019
Priority date	Feb 12, 2018
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

An air swirler arrangement comprises a coaxial arrangement of an inner and an outer air swirler passage. Each air swirler passage comprises a radial flow swirler. Air swirler arrangement comprises a coaxial arrangement of first, second and third members. Second member has radially extending upstream portion spaced axially from first member and a convergent portion. Third member has a radially extending upstream portion spaced axially from the upstream portion of second member and a radially inner surface having convergent and divergent downstream portions and a radially outer surface having a divergent downstream portion. First, second and third members the vanes of the radial flow swirlers is a monolithic structure. Plurality of circumferentially spaced passages are provided within the third member and each passage has an inlet in the surface and an outlet arranged to direct fluid onto the divergent portion of the surface or the surface of the third member.

First claim

The invention claimed is:

1. An air swirler arrangement comprising a coaxial arrangement of an inner air swirler passage and an outer air swirler passage, each air swirler passage comprising a radial flow swirler,
the air swirler arrangement comprising an annular first member arranged radially relative to a major axis of the air swirler arrangement, the annular first member having a central aperture,
an annular second member spaced axially from the annular first member and arranged coaxially with the major axis of the air swirler arrangement, the annular second member having a radially extending upstream portion and an axially extending convergent portion,
an annular third member arranged coaxially around the annular second member, the annular third member having a radially extending upstream portion spaced axially downstream from the radially extending upstream portion of the annular second member, the annular third member having a radially inner surface having an axially extending convergent portion and a divergent downstream portion and a radially outer surface having the divergent downstream portion,
a first plurality of circumferentially spaced swirl vanes of the radial flow swirler of the inner air swirler passage extending axially between the annular first member and the radially extending upstream portion of the annular second member,
a second plurality of circumferentially spaced swirl vanes of the radial flow swirler the outer air swirler passage extending axially between the radially extending upstream portion of the annular second member and the radially extending upstream portion of the annular third member,
the annular first member, the annular second member, the annular third member, the first plurality of swirl vanes and the second plurality of swirl vanes is a unitary monolithic structure,
a plurality of circumferentially spaced passages within the annular third member, wherein each circumferentially spaced passage has an inlet in the radially outer surface of the annular third member and an outlet arranged to direct fluid onto the divergent portion of the radially inner surface of the annular third member or arranged to direct fluid onto the divergent portion of the radially outer surface of the annular third member, wherein each circumferentially spaced passage has a convergent portion adjacent the outlet and each circumferentially spaced passage does not diverge between the convergent portion and the outlet.

2. The air swirler arrangement as claimed in claim 1 wherein each circumferentially spaced passage has a circular outlet or a rectangular outlet.

3. The air swirler arrangement as claimed in claim 1 wherein the outlet of each circumferentially spaced passage opens into an annular slot.

4. The air swirler arrangement as claimed in claim 1 wherein the outlet of each circumferentially spaced passage is arranged tangentially to the divergent portion of the radially outer surface of the third member.

5. The air swirler arrangement as claimed in claim 1 wherein the outlet of each circumferentially spaced passage is arranged at a shallow angle to the divergent portion of the radially inner surface of the third member.

6. The air swirler arrangement as claimed in claim 5 wherein the shallow angle is 20° or less.

7. The air swirler arrangement as claimed in claim 5 wherein the shallow angle is 15° or less.

8. The air swirler arrangement as claimed in claim 5 wherein the shallow angle is 10° or less.

9. The air swirler arrangement as claimed in claim 1 wherein each circumferentially spaced passage has one or more axially extending portions, and wherein each axially extending portion of the one or more axially extending portions has a circular cross-section.

10. The air swirler arrangement as claimed in claim 1 wherein each circumferentially spaced passage has one or more radially and axially extending portions, wherein each radially and axially extending portion of the one or more radially and axially extending portions is part circular in cross-section and has an angled roof defined by two intersecting tangents to the part circular portion, and wherein the angled roof defines the radially outer surface of the circumferentially spaced passage.

11. The air swirler arrangement as claimed in claim 1 wherein the third member has an annular chamber arranged therein.

12. The air swirler arrangement as claimed in claim 11 wherein at least some of the circumferentially spaced passages have a first portion connecting the inlet and the annular chamber and a second portion connecting the annular chamber and the outlet.

13. The air swirler arrangement as claimed in claim 11 wherein the annular chamber is arranged coaxially within the third member.

14. A combustion chamber comprising an upstream end wall having at least one aperture, each aperture having an air swirler arrangement arranged coaxially therein, each aperture having an associated fuel injector,
each air swirler arrangement comprising a coaxial arrangement of an inner air swirler passage and an outer air swirler passage, each air swirler passage comprising a radial flow swirler, the air swirler arrangement comprising an annular first member arranged radially relative to a major axis of the air swirler arrangement, the annular first member having a central aperture,
an annular second member spaced axially from the annular first member and arranged coaxially with the major axis of the air swirler arrangement, the annular second member having a radially extending upstream portion and an axially extending convergent portion,
an annular third member arranged coaxially around the annular second member, the annular third member having a radially extending upstream portion spaced axially from the radially extending upstream portion of the annular second member, the annular third member having a radially inner surface having a convergent portion and a divergent downstream portion and a radially outer surface having the divergent downstream portion,
a first plurality of circumferentially spaced swirl vanes extending axially between the annular first member and the radially extending upstream portion of the annular second member,
a second plurality of circumferentially spaced swirl vanes extending axially between the radially extending upstream. portion of the annular second member and the radially extending upstream portion of the annular third member,
the annular first member, the annular second member, the annular third member, the first plurality of swirl vanes and the second plurality of swirl vanes is a unitary monolithic structure,
a plurality of circumferentially spaced passages within the annular third member, wherein each circumferentially spaced passage has an inlet in the radially outer surface of the annular third member and an outlet arranged to direct fluid onto the divergent portion of the radially inner surface of the annular third member or arranged to direct fluid onto the divergent portion of the radially outer surface of the annular third member, wherein each circumferentially spaced passage has a convergent portion adjacent the outlet and each circumferentially spaced passage does not diverge between the convergent portion and the outlet, each air swirler arrangement having the fuel injector arranged in the central aperture in the annular first member.

15. The combustion chamber as claimed in claim 14 wherein the combustion chamber is an annular combustion chamber, and wherein the at least one aperture comprises a plurality of circumferentially spaced apertures.

16. A method of manufacturing an air swirler arran

Assignees

• Rolls Royce Plc

Inventors

• Freeman Richard
• Rafferty Christopher
• Jones Thomas
• Murphy Matthew
• Brown Nicholas M

Classifications

• B01F25/104

  characterised by the arrangement of the discharge opening · CPC title

• F23D11/383

  with swirl means · CPC title

• F23D2213/00

  Burner manufacture specifications · CPC title

• F23D11/00

  Burners using a direct spraying action of liquid droplets or vaporised liquid into the combustion space · CPC title

• F23C7/004

  using vanes · CPC title