Claims
- 1. A fuel injector for a gas turbine engine combustor, comprising:a forward endplate and an aft endplate longitudinally spaced from the forward end plate, the aft endplate having a fuel injector discharge port extending therethrough, the discharge port having an aft extremity that defines a fuel injector discharge plane; at least two cylindrical-arc scrolls extending longitudinally between the forward endplate and the aft endplate and cooperating with the endplates to bound a mixing chamber, each scroll defining a surface of partial revolution about a respective scroll centerline, the scroll centerlines being parallel to and equidistantly offset from a longitudinally extending fuel injector axis so that each adjacent pair of scrolls defines an entry slot having a length and a height and extending parallel to the axis for admitting a stream of primary combustion air into the mixing chamber, at least one of the scrolls including a longitudinally distributed array of fuel injection passages adjacent to the entry slot for injecting a primary fuel into the primary combustion air stream, the passage array being configured to inject the primary fuel nonuniformly along the length of the entry slot and comprising passages of at least two different classes, each class being distinguished by its capacity for injecting fuel into the primary combustion air stream, the passages being distributed along the length of the entry slot so that the distribution of passage classes, over at least portion of the length of the entry slot, is selected from the group consisting of substantially periodic distributions and bipolar distributions; and a centerbody having a longitudinally extending shell with a radially outer surface, the centerbody being coaxial with the fuel injector axis and defining a radially inner boundary of the mixing chamber.
- 2. The fuel injector of claim 1 wherein the bipolar distribution of passage classes is alternating over at least a portion of the length of the entry slot.
- 3. The fuel injector of claim 1 or 2 wherein each passage has a fluid flow metering area and the classes are distinguished by the metering area.
- 4. The fuel injector of claim 1 or 2 wherein the primary fuel injected through each fuel injection passage has a fuel penetration depth into the primary air stream, and the passage classes are distinguished by the penetration depth.
- 5. The fuel injector of claim 4 wherein the minimum fuel penetration depth of the passage array is at least about 30% and more preferably at least about 40% of the entry slot height and the maximum penetration depth is no more than about 80% and preferably no more than about 70% of the entry slot height.
- 6. The fuel injector of claim 4 wherein the minimum fuel penetration depth of the passage array is at least about 40% and no more than about 45% of the entry slot height and the maximum penetration depth is at least about 60% and no more than about 70% of the entry slot height.
- 7. A fuel injector for a gas turbine engine combustor, comprising:a forward endplate and an aft endplate longitudinally spaced from the forward end plate, the aft endplate having a fuel injector discharge port extending therethrough, the discharge port having an aft extremity that defines a fuel injector discharge plane; at least two cylindrical-arc scrolls extending longitudinally between the forward endplate and the aft endplate and cooperating with the endplates to bound a mixing chamber, each scroll defining a surface of partial revolution about a respective scroll centerline, the scroll centerlines being parallel to and equidistantly offset from a longitudinally extending fuel injector axis so that each adjacent pair of scrolls defines an entry slot having a length and extending parallel to the axis for admitting a stream of primary combustion air into the mixing chamber, at least one of the scrolls including a longitudinally distributed array of fuel injection passages adjacent to the entry slot for injecting a primary fuel into the primary combustion air stream, the passage array being configured to inject the primary fuel nonuniformly along the length of the entry slot and comprising passages of at least two different classes, each class being distinguished by its capacity for injecting fuel into the primary combustion air stream, the passages being distributed along the length of the entry slot so that the distribution of passage classes, over at least a portion of the length of the entry slot, is selected from the group consisting of substantially periodic distributions and bipolar distributions; and a centerbody having a longitudinally extending centerbody axis, a base, a bluff tip and a shell with a radially outer surface that extends longitudinally from the base to the tip, the centerbody being coaxial with the fuel injector axis and defining a radially inner boundary of the mixing chamber, the tip being substantially longitudinally aligned with the discharge plane, the centerbody having a fuel conduit extending therethrough and in communication with at least one fuel discharge opening in the tip for injecting a combustible fluid into the combustor.
- 8. A fuel injector for a gas turbine engine combustor, comprising:a forward endplate and an aft endplate longitudinally spaced from the forward end plate, the aft endplate having a fuel injector discharge port extending therethrough, the discharge port having an aft extremity that defines a fuel injector discharge plane; at least two cylindrical-arc scrolls extending longitudinally between the forward endplate and the aft endplate and cooperating with the endplates to bound a mixing chamber, each scroll defining a surface of partial revolution about a respective scroll centerline, the scroll centerlines being parallel to and equidistantly offset from a longitudinally extending fuel injector axis so that each adjacent pair of scrolls defines an entry slot parallel to the axis for admitting a stream of primary combustion air into the mixing chamber, at least one of the scrolls including a longitudinally distributed array of fuel injection passages adjacent to the entry slot for injecting a primary fuel into the primary combustion air stream, the passage array being configured to inject the primary fuel nonuniformly along the length of the entry slot and comprising passages of at least two different classes, each class being distinguished by its capacity for injecting fuel into the primary combustion air stream, the passages being distributed along the length of the entry slot so that the distribution of passage classes, over at least a portion of the length of the entry slot, is selected from the group consisting of substantially periodic distributions and bipolar distributions; and a centerbody having a longitudinally extending centerbody axis, a base, a bluff tip and a shell having a radially outer surface that extends longitudinally from the base to the tip, the shell surface comprising a curved portion that extends aftwardly from the base and a frustum portion that extends aftwardly from the curved portion toward the tip, the centerbody being coaxial with the fuel injector axis and defining a radially inner boundary of the mixing chamber, the tip being substantially longitudinally aligned with the discharge plane, the centerbody having a fuel conduit extending therethrough and in communication with at least one fuel discharge opening in the tip for injecting a combustible fluid into the combustor.
- 9. A fuel injector for a gas turbine engine combustor, comprising:a forward endplate and an aft endplate longitudinally spaced from the forward end plate, the aft endplate having a fuel injector discharge port extending therethrough, the discharge port having an aft extremity that defines a fuel injector discharge plane; at least two cylindrical-arc scrolls extending longitudinally between the forward endplate and the aft endplate and cooperating with the endplates to bound a mixing chamber, each scroll defining a surface of partial revolution about a respective scroll centerline, the scroll centerlines being parallel to and equidistantly offset from a longitudinally extending fuel injector axis so that each adjacent pair of scrolls defines an entry slot having a length and a height and extending parallel to the axis for admitting a stream of primary combustion air into the mixing chamber, at least one of the scrolls including a longitudinally distributed array of fuel injection passages, each having a fluid flow metering area, for injecting a primary fuel into the primary combustion air stream, the passage array being configured to inject the primary fuel nonuniformly along the length of the entry slot; and a centerbody having a longitudinally extending centerbody axis, a base, a tip and a shell having a radially outer surface that extends longitudinally from the base to the tip, the shell surface comprising a curved portion that extends aftwardly from the base and a frustum portion that extends aftwardly from the curved portion toward the tip, the centerbody being coaxial with the fuel injector axis and defining a radially inner boundary of the mixing chamber; wherein the entry slot has a forward section longitudinally coextensive with the curved portion of the centerbody and an aft section longitudinally coextensive with the frustum portion of the centerbody, the passage array is adjacent to the entry slot and comprises at least two classes of passages, the classes being distinguished from each other by the fluid flow metering area of the passages, and the passages are longitudinally distributed so that the distribution of passage classes is substantially periodic along the aft section of the entry slot, and so that passages belonging to the passage class having the largest metering area are excluded along the forward section of the entry slot.
- 10. A fuel injector for a gas turbine engine combustor, comprising:a forward endplate and an aft endplate longitudinally spaced from the forward end plate, the aft endplate having a fuel injector discharge ort extending therethrough, the discharge port having an aft extremity that defines a fuel injector discharge plane; at least two cylindrical-arc scrolls extending longitudinally between the forward and the aft endplate and cooperating with the endplates to bound a mixing chamber, each scroll defining a surface of partial revolution about a respective scroll centerline, the scroll centerlines being parallel to and equidistantly offset from a longitudinally extending fuel injector axis so that each adjacent pair of scrolls defines an entry slot having a length and a height and extending parallel to the axis for admitting a stream of primary combustion air into the mixing chamber, at least one of the scrolls including a longitudinally distributed array of fuel injection passages, each having a fluid flow metering area, for injecting a primary fuel into the primary combustion air stream, the passage array being configured to inject the primary fuel nonuniformly along the length of the entry slot; and a centerbody having a longitudinally extending centerbody axis, a base, a tip and a shell having a radially outer surface that extends longitudinally from the base to the tip, the shell surface comprising a curved portion that extends aftwardly from the base and a frustum portion that extends aftwardly from the curved portion toward the tip, the centerbody being coaxial with the fuel injector axis and defining a radially inner boundary of the mixing chamber; wherein the entry slot has a forward section longitudinally coextensive with the curved portion of the centerbody and an aft section longitudinally coextensive with the frustum portion of the centerbody, the passage array is adjacent to the entry slot and comprises two classes of passages, one class having a small fluid flow metering area and the other class having a large metering area, the longitudinal distribution of passage classes is bipolar along the aft section of the entry slot, and only passages of the small area class are distributed along the forward section of the entry slot.
- 11. The fuel injector of claim 10 wherein the distribution of passage classes is alternating along the aft section of the entry slot.
- 12. A fuel injector for a gas turbine engine combustor, comprising:a forward endplate and an aft endplate longitudinally spaced from the forward end plate, the aft endplate having a fuel injector discharge port extending therethrough, the discharge port having an aft extremity that defines a fuel injector discharge plane; at least two cylindrical-arc scrolls extending longitudinally between the forward endplate and the aft endplate and cooperating with the endplates to bound a mixing chamber, each scroll defining a surface of partial revolution about a respective scroll centerline, the scroll centerlines being parallel to and equidistantly offset from a longitudinally extending fuel injector axis so that each adjacent pair of scrolls defines an entry slot having a length and a height and extending parallel to the axis for admitting a stream of combustion air into the mixing chamber, at least one of the scrolls including a longitudinally distributed array of fuel injection passages, each having a fluid flow metering area, for injecting a primary fuel into the primary combustion air stream, the passage array being configured to inject the primary fuel nonuniformly along the length of the entry slot; and a centerbody having a longitudinally extending centerbody axis, a base, a tip and a shell having a radially outer surface that extends longitudinally from the base to the tip, the shell surface comprising a curved portion that extends aftwardly from the base and a frustum portion that extends aftwardly from the curved portion toward the tip, the centerbody being coaxial with the fuel injector axis and defining a radially inner boundary of the mixing chamber; wherein the primary fuel injected through each injection passage has a fuel penetration depth into the primary combustion air stream, the entry slot has a forward section longitudinally coextensive with the curved portion of the centerbody and an aft section longitudinally coextensive with the frustum portion of the centerbody, the passage array is adjacent to the entry slot and comprises at least two classes of passages, the classes being distinguished from each other by a fuel penetration depth and the longitudinal distribution of passage classes is substantially periodic along the aft section of the entry slot, and passages belonging to the class having the deepest penetration depth are excluded along the forward section of the entry slot.
- 13. A fuel injector for a gas turbine engine combustor, comprising:a forward endplate and an aft endplate longitudinally spaced from the forward end plate, the aft endplate having a discharge port having an aft extremity that defines a fuel injector discharge plane; at least two cylindrical-arc scrolls extending longitudinally between the forward endplate and the aft endplate and cooperating with the endplates to bound a mixing chamber, each scroll defining a surface of partial revolution about a respective scroll centerline, the scroll centerlines being parallel to and equidistantly offset from a longitudinally extending fuel injector axis so that each adjacent lair of scrolls defines an entry slot having a length and a height and extending parallel to the axis for admitting a stream of primary combustion air into the mixing chamber, at least one of the scrolls including a longitudinally distributed array of fuel injection passages, each having a fluid flow metering area, for injecting a primary fuel into the primary combustion air stream, the passage array being configured to inject the primary fuel nonuniformly along the length of the entry slot; and a centerbody having a longitudinally extending centerbody axis, a base, a tip and a shell having a radially outer surface that extends longitudinally from the base to the tip, the shell surface comprising a curved portion that extends aftwardly from the base and a frustum portion that extends aftwardly from the curved portion toward the tip, the centerbody being coaxial with the fuel injector axis and defining a radially inner boundary of the mixing chamber; wherein the primary fuel injected through each injection passage has a penetration depth into the primary combustion air stream, the entry slot has a forward section longitudinally coextensive with the curved portion of the centerbody and an aft section longitudinally coextensive with the frustum portion of the centerbody, the passage array is adjacent to the entry slot and comprises two classes of passages, one class having a shallow fuel penetration depth and the other class having a deep fuel penetration depth, the longitudinal distribution of passage classes is bipolar along the aft section of the entry slot, and only passages of the shallow penetration depth class are distributed along the forward section of the entry slot.
- 14. The fuel injector of claim 13 wherein the distribution of passage classes is alternating along the aft section of the entry slot.
- 15. The fuel injector of claim 12, 13 or 14 wherein the minimum fuel penetration depth of the passage array is at least about 30% and more preferably at least about 40% of the entry slot height and the maximum penetration depth is no more than about 80% and preferably no more than about 70% of the entry slot height.
- 16. The fuel injector of claim 12, 13 or 14 wherein the minimum fuel penetration depth of the passage array is at least about 40% and no more than about 45% of the entry slot height and the maximum penetration depth of the passage array is at least about 60% and no more than about 70% of the entry slot height.
- 17. The fuel injector of claim 12, 13 or 14 wherein the maximum fuel penetration depth of the passage array is shallow enough to preclude the primary fuel from entering the fluid boundary layer attached to the centerbody.
- 18. A fuel injector for a gas turbine engine combustor, comprising:a forward endplate and an aft endplate longitudinally spaced from the forward end plate, the aft endplate having a fuel injector discharge port extending therethrough, the discharge port having an aft extremity that defines a fuel injector discharge plane; at least two cylindrical-arc scrolls extending longitudinally between the forward endplate and the aft endplate and cooperating with the endplates to bound a mixing chamber, each scroll defining a surface of partial revolution about a respective scroll centerline, the scroll centerlines being parallel to and equidistantly offset from a longitudinally extending fuel injector axis so that each adjacent pair of scrolls defines an entry slot parallel to the axis for admitting a stream of primary combustion air into the mixing chamber, at least one of the scrolls including a longitudinally distributed array of fuel injection passages adjacent to the entry slot for injecting a primary fuel into the primary combustion air stream; a centerbody having a longitudinally extending centerbody axis, a base, a bluff tip and a shell having a radially outer surface that extends longitudinally from the base to the tip, the shell surface comprising a curved portion that extends aftwardly from the base and a frustum portion that extends aftwardly from the curved portion toward the tip, the centerbody being coaxial with the fuel injector axis and defining a radially inner boundary of the mixing chamber, the tip being substantially longitudinally aligned with the discharge plane, the centerbody having a fuel conduit extending therethrough and in communication with at least one opening in the tip for injecting a combustible fluid into the combustor, the fuel injector also including a secondary air tube for admitting secondary combustion air into the interior of the centerbody and at least one air discharge opening in the centerbody tip for discharging the secondary combustion air into the combustor; wherein the entry slot has a forward section longitudinally coextensive with the curved portion of the centerbody and an aft section longitudinally coextensive with the frustum portion of the centerbody, the passage array comprising passages having a small fluid flow metering area and other passages having a large metering area, the large and small area passages alternating along the aft section of the entry slot and having only small area passages distributed along the forward section of the entry slot.
CROSS REFERENCE TO RELATED APPLICATIONS
This application contains subject matter related to commonly owned U.S. patent application Ser. No. 08/771,408 entitled “Flame Disgorging Two Stream Tangential Entry Nozzle” filed on Dec. 20, 1996, now U.S. Pat. No. 5,899,076 and commonly owned patent application Ser. No. 08/771,409 entitled “Method of Disgorging Flames from a Two Stream Tangential Entry Nozzle” filed on Dec. 20, 1996, now U.S. Pat. No. 5,896,739.
US Referenced Citations (28)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0 433 790 A1 |
Jul 1990 |
EP |
0 849 530 A2 |
Jun 1998 |
EP |
Non-Patent Literature Citations (1)
Entry |
“Acoustic Sensitivities Of Lean-Premixed Fuel Injectors In A Single Nozzle Rig”, Donald W. Kendrick, Torger J. Anderson, William A. Sowa and Timothy S. Snyder; prospective publication date is Jun. 2, 1998. |