Multipoint fuel injection arrangements

Patent metadata

Field	Value
Publication number	US-9644844-B2
Application number	US-201213664795-A
Country	US
Kind code	B2
Filing date	Oct 31, 2012
Priority date	Nov 3, 2011
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

A multipoint fuel injection system includes a plurality of fuel manifolds. Each manifold is in fluid communication with a plurality of injectors arranged circumferentially about a longitudinal axis for multipoint fuel injection. The injectors of separate respective manifolds are spaced radially apart from one another for separate radial staging of fuel flow to each respective manifold.

First claim

What is claimed is:

1. A multipoint fuel injection system comprising:
a plurality of fuel manifolds, wherein each manifold is in fluid communication with a plurality of injectors arranged circumferentially about a longitudinal axis in an annular array for multipoint fuel injection in an annular combustor, wherein the injectors of separate respective manifolds are spaced radially apart from one another for separate radial staging of fuel flow to each respective manifold, wherein a middle set of the injectors are pilot injectors, wherein injectors inboard and outboard of the middle set of injectors are airblast injectors, wherein each injector defines a flow trajectory such that the flow trajectory of each set of radially adjacent injectors converges generally towards a respective point of convergence, wherein the points of convergence all generally lie on a circle,
wherein there are five manifolds each in fluid communication with a plurality of respective injectors arranged circumferentially about the longitudinal axis, wherein the injectors of a first one of the manifolds are an inboard set of injectors, wherein the injectors of a second one of the manifolds are an inner intermediate set of injectors outboard of the inboard set, wherein the injectors of a third one of the manifolds are a middle set of injectors outboard of the inner intermediate set, wherein the injectors of a fourth one of the manifolds are an outer intermediate set of injectors outboard of the middle set, and wherein the injectors of a fifth one of the manifolds are an outboard set of injectors outboard of the outer intermediate set,
wherein each injector of the inboard set of injectors includes:
an inner air swirler defining an interior flow passage configured and adapted for fluid communication of compressor discharge air through the interior flow passage such that swirl is imparted on air flow through the interior flow passage; and
an outer air cap mounted outboard of the inner air swirler with a fuel passage defined between the inner air swirler and the outer air cap, the fuel passage including a discharge outlet between downstream portions of the inner air swirler and outer air cap for issuing fuel for combustion, wherein the outer air cap defines an outer air circuit configured for substantially swirl-free injection of compressor discharge air outboard of the fuel passage,

wherein each injector of the inner intermediate set of injectors includes:
an inner air swirler defining an interior flow passage configured and adapted for fluid communication of compressor discharge air through the interior flow passage such that swirl is imparted on air flow through the interior flow passage; and
an outer air cap mounted outboard of the inner air swirler with a fuel passage defined between the inner air swirler and the outer air cap, the fuel passage including a discharge outlet between downstream portions of the inner air swirler and outer air cap for issuing fuel for combustion, wherein the outer air cap defines an outer air circuit configured for substantially swirl-free injection of compressor discharge air outboard of the fuel passage,

wherein each injector of the outer intermediate set of injectors includes:
an inner air swirler defining an interior flow passage configured and adapted for fluid communication of compressor discharge air through the interior flow passage such that swirl is imparted on air flow through the interior flow passage; and
an outer air cap mounted outboard of the inner air swirler with a fuel passage defined between the inner air swirler and the outer air cap, the fuel passage including a discharge outlet between downstream portions of the inner air swirler and outer air cap for issuing fuel for combustion, wherein the outer air cap defines an outer air circuit configured for substantially swirl-free injection of compressor discharge air outboard of the fuel passage,

wherein each injector of the outboard set of injectors includes:
an inner air swirler defining an interior flow passage configured and adapted for fluid communication of compressor discharge air through the interior flow passage such that swirl is imparted on air flow through the interior flow passage; and
an outer air cap mounted outboard of the inner air swirler with a fuel passage defined between the inner air swirler and the outer air cap, the fuel passage including a discharge outlet between downstream portions of the inner air swirler and outer air cap for issuing fuel for combustion, wherein the outer air cap defines an outer air circuit configured for substantially swirl-free injection of compressor discharge air outboard of the fuel passage.

2. A multipoint fuel injection system as recited in claim 1 , where the injectors of each of the manifolds are circumferentially staggered from radially adjacent injectors of other manifolds.

3. A multipoint fuel injection system as recited in claim 1 , further comprising a combustor having an annular upstream wall, an outboard wall extending downstream from the upstream wall, and an inboard wall extending downstream from the upstream wall and opposed to the outboard wall, the inboard and outboard walls defining a combustor outlet configured to deliver combustion products to a downstream turbine, wherein the injectors are mounted to the upstream wall with the manifolds outside the combustor.

4. A multipoint fuel injection system as recited in claim 3 , wherein the injectors and combustor are configured so that about 85% of total air flow through the combustor is supplied through the injectors.

5. A multipoint fuel injection system as recited in claim 3 , wherein the inboard and outboard walls of the combustor converge towards one another in a downstream direction from the injectors, and wherein at least some of the injectors are oriented oblique to the longitudinal axis to reduce flame impingement on the inboard and outboard walls of the combustor.

6. A multipoint fuel injection system as recited in claim 1 , wherein the injectors of the outboard and outer intermediate sets of injectors are angled inward toward a respective centerline defined by the longitudinal axis.

7. A multipoint fuel injection system as recited in claim 1 , wherein the injectors of the outboard set of injectors are more angled relative to the centerline than are those of the outer intermediate set.

8. A multipoint fuel injection system as recited in claim 1 , wherein the injectors of the inboard and inner intermediate sets of injectors are angled outward relative to a respective centerline defined by the longitudinal axis.

9. A multipoint fuel injection system as recited in claim 8 , wherein the injectors of the inboard set of injectors are more angled relative to the centerline than are those of the inner intermediate set.

10. A multipoint fuel injection system as recited in claim 1 , wherein the injectors of the middle set of injectors are aligned along a respective centerline defined from the injectors in the middle set of injectors toward the center of a combustor outlet downstream of the middle set of injectors.

11. A multipoint fuel injection system as recited in claim 1 , wherein each injector of the middle set of injectors that includes a central pressure atomizer surrounded by a nozzle body having a plurality of cylindrical bores defined therethrough configured and adapted for imparting swirl on a flow of air flowing through the nozzle body.

12. A multipoint fuel injection system as recited in claim 1 , wherein the inboard and outboard sets of injectors are each configured to supply about 20% of the combustion air flow into the combustor, wherein the inner and outer intermediate sets of inject

Assignees

• Delavan Inc
• Delavan Inc

Inventors

• Prociw Lev Alexander

Classifications

• F23C2201/20

  Burner staging · CPC title

• F23R3/28 Primary

  characterised by the fuel supply (burners F23D) · CPC title

• F02C7/222

  Fuel flow conduits, e.g. manifolds · CPC title

• F23R3/346 Primary

  for staged combustion · CPC title

• F05D2240/35

  Combustors or associated equipment · CPC title