Staged gas turbine combustion chamber with counter swirling arrays of radial vanes having interjacent fuel injection

Claim 2

A gas turbine engine combustion chamber having a longitudinal axis and comprising first air intake means, primary fuel injector means and a first fuel and air mixing zone, said first fuel and air mixing zone being defined by at least one annular wall having an upstream end and an upstream wall connected to said upstream end of said annular wall, said annular wall having a longitudinal axis extending coaxially with said longitudinal axis of said combustion chamber at least partly along said axes, said upstream wall having at least one aperture, said first air intake means comprising at least one first flow swirler and at least one second flow swirler for introducing first air into said first fuel and air mixing zone through said aperture in said upstream wall, said first flow swirler and said second flow swirler being disposed at least partly radially with respect to said longitudinal axis and upstream of said annular wall along said axis with said first flow swirler being located closer to said end wall than said second flow swirler, said first flow swirler having vanes to swirl air in one direction, said second flow swirler having vanes to swirl air in a direction generally opposite to said one direction, said vanes of each said flow swirler defining passages therebetween, said primary fuel injector means being located to supply fuel into at least one of said passages between said vanes of said first flow swirler and said vanes of said second flow swirler.

Claim 3

The invention as claimed in claim 1, wherein said combustion chamber includes at least one pilot fuel injector aligned with said aperture in said end wall to supply fuel through said aperture into said first fuel and air mixing zone.

Claim 4

The invention as claimed in claim 1, wherein said primary fuel injector means is located to supply fuel into each of said passages between said vanes of said first flow swirler.

Claim 5

The invention as claimed in claim 1, in which said primary fuel injector means is located to supply fuel into all the passages defined between said vanes of said second flow swirler.

Claim 6

The invention as claimed in claim 1, in which said passages have radially outer regions and said primary fuel injector means is located to supply fuel to said radially outer regions.

Claim 7

The invention as claimed in claim 1, wherein said primary fuel injector means comprises a hollow cylindrical member located to extend axially with respect to said combustion chamber, said cylindrical member having a plurality of apertures spaced apart along said cylindrical member to inject fuel into said passage.

Claim 8

The invention as claimed in claim 6, wherein said apertures are positioned to direct the fuel radially inwardly relative to said axis of said combustion chamber.

Claim 9

The invention as claimed in claim 1, in which said combustion chamber is tubular and has a single aperture in said upstream wall.

Claim 10

The invention as claimed in claim 2, further comprising secondary air intake means, secondary fuel injector means and a secondary fuel and air mixing zone, said secondary fuel and air mixing zone being annular and surrounding said first fuel and air mixing zone, said secondary fuel and air mixing zone having a radially outer extremity defined by a second annular wall, said secondary fuel injector means being located to supply fuel into said upstream end of said secondary fuel and air mixing zone, said secondary fuel and air mixing zone having a downstream end in fluid flow communication with a secondary combustion zone provided in said combustion chamber downstream of said first fuel and air mixing zone.

Claim 11

The invention as claimed in claim 9, wherein said annular wall has a first portion defining said first fuel and air mixing zone, a second portion of increased diameter downstream of said first portion and defining said secondary combustion zone, and a third frusto-conical portion interconnecting the first and second portions.

Claim 12

The invention as claimed in claim 10, wherein said downstream end of said first portion of said second annular wall reduces in diameter to a throat.

Claim 13

The invention as claimed in claim 9, in which said secondary air intake means is downstream of said first air intake means.

Claim 14

The invention as claimed in claim 9, wherein said secondary fuel and air mixing zone is defined at its radially inner extremity by a third annular wall.

Claim 15

The invention as claimed in claim 10, wherein said third frusto-conical portion has a plurality of equally circumferentially spaced apertures for directing a secondary fuel and air mixture from said secondary fuel and air mixing zone as a plurality of jets in a downstream direction towards said axis of said combustion chamber.

Claim 16

The invention as claimed in claim 14, in which said apertures are slots.

Claim 17

The invention as claimed in claim 10, in which said second annular wall has a downstream end which is secured to said third frusto-conical portion of said second annular wall.

Claim 18

The invention as claimed in claim 13, wherein said combustion chamber has means for supplying cooling air to an annular chamber defined between said annular wall and said third annular wall.

Claim 19

The invention as claimed in claim 9, wherein said secondary fuel injector means comprises a plurality of equi-circumferentially spaced injectors.

Claim 20

The invention as claimed in claim 9, further comprising tertiary air intake means, tertiary fuel injector means and a tertiary fuel and air mixing zone, said tertiary fuel and air mixing zone being annular in shape and surrounding said secondary combustion zone, said tertiary fuel and air mixing zone being defined at its radially outer extremity by a fourth annular wall, said tertiary fuel injector means being located to supply fuel into the upstream end of said tertiary fuel and air mixing zone, said tertiary fuel and air mixing zone being in fluid flow communication at its downstream end with a tertiary combustion zone provided in said combustion chamber downstream of said secondary combustion zone.

Claim 21

The invention as claimed in claim 19 wherein said annular wall has a fourth portion of larger diameter than said second portion downstream of said second portion and defining the tertiary combustion zone, a fifth frusto-conical portion interconnecting said second and fourth portions.

Claim 22

The invention as claimed in claim 19, wherein said downstream end of said first portion of said second annular wall reduces in diameter to a throat.

Claim 23

The invention as claimed in claim 19, in which said tertiary air intake means is downstream of said second air intake means.

Claim 24

The invention as claimed in claim 19, wherein said tertiary fuel and air mixing zone is defined at its radially inner extremity by a fifth annular wall.

Claim 25

The invention as claimed in claim 20, wherein said fifth frusto-conical portion has a plurality of equi-circumferentially spaced apertures for directing a tertiary fuel and air mixture from said tertiary fuel and air mixing zone as a plurality of jets in a downstream direction towards said axis of said combustion chamber.

Claim 26

The invention as claimed in claim 24, in which said apertures are slots.

Claim 27

The invention as claimed in claim 20, in which said fourth annular wall has a downstream end which is secured to said fifth frusto-conical portion of said annular wall.

Claim 28

The invention as claimed in claim 19, wherein said secondary fuel injector means comprises a plurality of equi-circumferentially spaced injectors.

Claim 29

A method as claimed in claim 27 in which the predetermined output level is 35-40% power.

Claim 30

A method as claimed in claim 28 in which the proportion of fuel supplied from the primary fuel injector means varies from 75% to 50% of the total fuel supplied into the combustion chamber from 40% to 100% output power level.

Claim 33

A method as claimed in claim 30 in which the predetermined output power level is 35 to 40% power.

Claim 36

The method as claimed in claim 32 introducing the step of injecting gas fuel with said primary fuel injector means.

Claim 37

The method as claimed in claim 32 including the step of injecting evaporated liquid fuel with said primary fuel injector means.

Claim 38

A gas turbine engine combustion chamber having a longitudinal axis and comprising first air intake means, primary fuel injector means and a first fuel and air mixing zone, said first fuel and air mixing zone being defined by at least one annular wall having an upstream end and an upstream wall connected to said upstream end of said annular wall, said annular wall having a longitudinal axis extending coaxially with said longitudinal axis of said combustion chamber at least partly along said axes, said upstream wall having at least one aperture, said first air intake means comprising at least one first flow swirler and at least one second flow swirler for introducing first air into said first fuel and air mixing zone through said aperture in said upstream wall, said first flow swirler and said second flow swirler being disposed at least partly radially with respect to said longitudinal axis and upstream of said annular wall along said axis with said first flow swirler being located closer to said end wall than said second flow swirler, said first flow swirler having vanes to swirl air in one direction, said second flow swirler having vanes to swirl air in a direction generally opposite to said one direction, said vanes of each said flow swirler defining passages therebetween, said primary fuel injector means being located to supply fuel into at least one of said passages between said vanes of said first flow swirler and said vanes of said second flow swirler, said combustion chamber including at least one pilot fuel injector aligned with said aperture in said end wall to supply fuel through said aperture into said first fuel and air mixing zone, said combustion chamber further comprising secondary air intake means, secondary fuel injector means and a secondary fuel and air mixing zone, said secondary fuel and air mixing zone being annular and surrounding said first fuel and air mixing zone, said secondary fuel and air mixing zone having a radially outer extremity defined by a second annular wall, said secondary fuel injector means being located to supply fuel into said upstream end of said secondary fuel and air mixing zone, said secondary fuel and air mixing zone having a downstream end in fluid flow communication with a secondary combustion zone provided in said combustion chamber downstream of said first fuel and air mixing zone, said annular wall having a first portion defining said first fuel and air mixing zone, a second portion of increased diameter downstream of said first portion and defining said secondary combustion zone, and a third frusto-conical portion interconnecting the first and second portions, said downstream end of said first portion of said second annular wall reducing in diameter to a throat.

Claim 39

A gas turbine engine combustion chamber having a longitudinal axis and comprising first air intake means, primary fuel injector means and a first fuel and air mixing zone, said first fuel and air mixing zone being defined by at least one annular wall having an upstream end and an upstream wall connected to said upstream end of said annular wall, said annular wall having a longitudinal axis extending coaxially with said longitudinal axis of said combustion chamber at least partly along said axes, said upstream wall having at least one aperture, said first air intake means comprising at least one first flow swirler and at least one second flow swirler for introducing first air into said first fuel and air mixing zone through said aperture in said upstream wall, said first flow swirler and said second flow swirler being disposed at least partly radially with respect to said longitudinal axis and upstream of said annular wall along said axis with said first flow swirler being located closer to said end wall than said second flow swirler, said first flow swirler having vanes to swirl air in one direction, said second flow swirler having vanes to swirl air in a direction generally opposite to said one direction, said vanes of each said flow swirler defining passages therebetween, said primary fuel injector means being located to supply fuel into at least one of said passages between said vanes of said first flow swirler and said vanes of said second flow swirler, said combustion chamber including at least one pilot fuel injector aligned with said aperture in said end wall to supply fuel through said aperture into said first fuel and air mixing zone, said combustion chamber further comprising secondary air intake means, secondary fuel injector means and a secondary fuel and air mixing zone, said secondary fuel and air mixing zone being annular and surrounding said first fuel and air mixing zone, said secondary fuel and air mixing zone having a radially outer extremity defined by a second annular wall, said secondary fuel injector means being located to supply fuel into said upstream end of said secondary fuel and air mixing zone, said secondary fuel and air mixing zone having a downstream end in fluid flow communication with a secondary combustion zone provided in said combustion chamber downstream of said first fuel and air mixing zone, said annular wall having a first portion defining said first fuel and air mixing zone, a second portion of increased diameter downstream of said first portion and defining said secondary combustion zone, and a third frusto-conical portion interconnecting the first and second portions, said downstream end of said first portion of said second annular wall reducing in diameter to a throat.

Claim 40

A gas turbine engine combustion chamber having a longitudinal axis and comprising first air intake means, primary fuel injector means and a first fuel and air mixing zone, said first fuel and air mixing zone being defined by at least one annular wall having an upstream end and an upstream wall connected to said upstream end of said annular wall, said annular wall having a longitudinal axis extending coaxially with said longitudinal axis of said combustion chamber at least partly along said axes, said upstream wall having at least one aperture, said first air intake means comprising at least one first flow swirler and at least one second flow swirler for introducing first air into said first fuel and air mixing zone through said aperture in said upstream wall, said first flow swirler and said second flow swirler being disposed at least partly radially with respect to said longitudinal axis and upstream of said annular wall along said axis with said first flow swirler being located closer to said end wall than said second flow swirler, said first flow swirler having vanes to swirl air in one direction, said second flow swirler having vanes to swirl air in a direction generally opposite to said one direction, said vanes of each said flow swirler defining passages therebetween, said primary fuel injector means being located to supply fuel into at least one of said passages between said vanes of said first flow swirler and said vanes of said second flow swirler, said combustion chamber including at least one pilot fuel injector aligned with said aperture in said end wall to supply fuel through said aperture into said first fuel and air mixing zone, said combustion chamber further comprising secondary air intake means, secondary fuel injector means and a secondary fuel and air mixing zone, said secondary fuel and air mixing zone being annular and surrounding said first fuel and air mixing zone, said secondary fuel and air mixing zone having a radially outer extremity defined by a second annular wall, said secondary fuel injector means being located to supply fuel into said upstream end of said secondary fuel and air mixing zone, said secondary fuel and air mixing zone having a downstream end in fluid flow communication with a secondary combustion zone provided in said combustion chamber downstream of said first fuel and air mixing zone, said combustion chamber further comprising tertiary air intake means, tertiary fuel injector means and a tertiary fuel and air mixing zone, said tertiary fuel and air mixing zone being annular in shape and surrounding said secondary combustion zone, said tertiary fuel and air mixing zone being defined at its radially outer extremity by a fourth annular wall, said tertiary fuel injector means being located to supply fuel into the upstream end of said tertiary fuel and air mixing zone, said tertiary fuel and air mixing zone being in fluid flow communication at its downstream end with a tertiary combustion zone provided in said combustion chamber downstream of said secondary combustion zone, said annular wall having a fourth portion of larger diameter than said second portion downstream of said second portion and defining the tertiary combustion zone, a fifth frusto-conical portion interconnecting said second and fourth portions.

Claim 41

A gas turbine engine combustion chamber having a longitudinal axis and comprising first air intake means, primary fuel injector means and a first fuel and air mixing zone, said first fuel and air mixing zone being defined by at least one annular wall having an upstream end and an upstream wall connected to said upstream end of said annular wall, said annular wall having a longitudinal axis extending coaxially with said longitudinal axis of said combustion chamber at least partly along said axes, said upstream wall having at least one aperture, said first air intake means comprising at least one first flow swirler and at least one second flow swirler for introducing first air into said first fuel and air mixing zone through said aperture in said upstream wall, said first flow swirler and said second flow swirler being disposed at least partly radially with respect to said longitudinal axis and upstream of said annular wall along said axis with said first flow swirler being located closer to said end wall than said second flow swirler, said first flow swirler having vanes to swirl air in one direction, said second flow swirler having vanes to swirl air in a direction generally opposite to said one direction, said vanes of each said flow swirler defining passages therebetween, said primary fuel injector means being located to supply fuel into at least one of said passages between said vanes of said first flow swirler and said vanes of said second flow swirler, said combustion chamber including at least one pilot fuel injector aligned with said aperture in said end wall to supply fuel through said aperture into said first fuel and air mixing zone, said combustion chamber further comprising secondary air intake means, secondary fuel injector means and a secondary fuel and air mixing zone, said secondary fuel and air mixing zone being annular and surrounding said first fuel and air mixing zone, said secondary fuel and air mixing zone having a radially outer extremity defined by a second annular wall, said secondary fuel injector means being located to supply fuel into said upstream end of said secondary fuel and air mixing zone, said secondary fuel and air mixing zone having a downstream end in fluid flow communication with a secondary combustion zone provided in said combustion chamber downstream of said first fuel and air mixing zone, said combustion chamber further comprising tertiary air intake means, tertiary fuel injector means and a tertiary fuel and air mixing zone, said tertiary fuel and air mixing zone being annular in shape and surrounding said secondary combustion zone, said tertiary fuel and air mixing zone being defined at its radially outer extremity by a fourth annular wall, said tertiary fuel injector means being located to supply fuel into the upstream end of said tertiary fuel and air mixing zone, said tertiary fuel and air mixing zone being in fluid flow communication at its downstream end with a tertiary combustion zone provided in said combustion chamber downstream of said secondary combustion zone, said annular wall having a fourth portion of larger diameter than said second portion downstream of said second portion and defining the tertiary combustion zone, a fifth frusto-conical portion interconnecting said second and fourth portions.

Claim 42

The invention as claimed in claim 36 wherein the downstream end of said second portion of said annular wall reduces in diameter to a throat.