Fuel injector and swirler assembly with lobed mixer
Disclosed is a gas turbine fuel injector and swirler assembly, including: a delivery tube structure arranged on a central axis of the fuel injector and swirler assembly, a first fuel supply channel arranged in the delivery tube structure, a shroud surrounding the delivery tube structure, swirl vanes arranged between the delivery tube structure and the shroud, a radial passage in each swirl vane, communicating with the first fuel supply channel, a set of apertures open between the radial passage and the exterior surface of said each swirl vane, wherein a second fuel supply channel is arranged in the delivery tube structure extending to a downstream end of the delivery tube structure and a mixer with lobes for fuel injection is arranged at the downstream end. Further disclosed is an assembly method for assembling a fuel injector and swirler assembly.
1. A gas turbine fuel injector and swirler assembly, comprising:
a delivery tube structure arranged on a central axis of the fuel injector and swirler assembly;
a first fuel supply channel arranged in the delivery tube structure;
a shroud surrounding the delivery tube structure;
a plurality of swirl vanes arranged between the delivery tube structure and the shroud;
a radial passage in each swirl vane, communicating with the first fuel supply channel;
a set of apertures open between the radial passage and the exterior surface of each swirl vane; and
a second fuel supply channel arranged in the delivery tube structure extending to a downstream end of the delivery tube structure,
wherein a mixer with a plurality of lobes for fuel injection is arranged at the downstream end.
2. The fuel injector and swirler assembly as claimed in claim 1 , wherein the delivery tube structure comprises coaxial cylindrical inner and outer tubes, providing the first fuel supply channel in the inner tube and forming the annular second fuel supply channel between the inner and outer tubes.
3. The fuel injector and swirler assembly as claimed in claim 1 , wherein each lobe of the mixer is located directly downstream a swirl vane.
4. The fuel injector and swirler assembly as claimed in claim 1 , wherein a number of lobes is equal to a number of swirl vanes.
5. The fuel injector and swirler assembly as claimed in claim 1 , wherein the lobed mixer has a twist.
6. The fuel injector and swirler assembly as claimed in claim 5 , wherein the twist of the lobed mixer follows a swirl induced by the plurality of swirl vanes.
7. The fuel injector and swirler assembly as claimed in claim 5 , wherein a twist angle of the lobed mixer is up to 45° .
8. The fuel injector and swirler assembly as claimed in claim 1 , wherein a height of each lobe is up to 0.5 times an annulus height of the shroud.
9. The fuel injector and swirler assembly as claimed in claim 1 , wherein a ratio between a height and a width of each lobe is between 0 and 8.
10. The fuel injector and swirler assembly as claimed in claim 9 , wherein the ratio between the height and the width of the plurality of lobes is 4.
11. The fuel injector and swirler assembly as claimed in claim 1 , wherein a grain is arranged on a central axis of the lobed mixer.
12. A combustion system, comprising:
a gas turbine fuel injector and swirler assembly as claimed in claim 1 .
13. The combustion system as claimed in claim 12 , wherein the delivery tube structure comprises coaxial cylindrical inner and outer tubes, providing the first fuel supply channel in the inner tube and forming the annular second fuel supply channel between the inner and outer tubes.
14. The combustion system as claimed in claim 12 , wherein each lobe of the mixer is located directly downstream a swirl vane.
15. The combustion system as claimed in claim 12 , wherein a number of lobes is equal to a number of swirl vanes.
16. The combustion system as claimed in claim 12 , wherein the lobed mixer has a twist.
17. The combustion system as claimed in claim 16 , wherein the twist of the lobed mixer follows a swirl induced by the plurality of swirl vanes.
18. The combustion system as claimed in claim 16 , wherein a twist angle of the lobed mixer is up to 45°.
19. The combustion system as claimed in claim 12 , wherein a height of each lobe is up to 0.5 times an annulus height of the shroud.
20. A gas turbine, comprising:
a combustion system as claimed in claim 12 .