Fuel plenum for a fuel nozzle and method of making same
A fuel plenum for a fuel nozzle assembly includes a gaseous fuel conduit, a conduit passage, and a liquid fuel conduit. Said gaseous fuel conduit received at a first end of said fuel plenum. Said fuel plenum is configured to distribute gaseous fuel received from said gaseous fuel conduit. Said conduit passage extends from the first end to a second end of said fuel plenum. Said conduit passage is at least partially defined by at least one interior wall of said fuel plenum. Said liquid fuel conduit defined by an outer wall and a portion of said liquid fuel conduit extending through said conduit passage. Said liquid fuel conduit outer wall is offset from said at least one interior wall.
1. A fuel nozzle assembly comprising:
a gaseous fuel conduit circumferentially surrounding an axial centerline of said fuel nozzle assembly;
a liquid fuel conduit comprising an upstream section, a middle section, and a downstream section in serial flow communication, each of said upstream, middle, and downstream sections extending axially, wherein said upstream section is at a first radial distance from said centerline, said middle section is at a second radial distance from said centerline, and said downstream section is at a third radial distance from said centerline, and wherein the first, second, and third distances are different from each other; and
a fuel plenum comprising an upstream end, a downstream end, and a plurality of chambers extending between said upstream and downstream ends, said chambers being in flow communication with said gaseous fuel conduit, said middle section of said liquid fuel conduit extending through said fuel plenum from said upstream end to said downstream end.
2. The fuel nozzle assembly of claim 1 , wherein said portion upstream section of said liquid fuel conduit is spaced apart from said gaseous fuel conduit.
3. The fuel nozzle assembly of claim 1 , wherein a downstream end of said middle section of said liquid fuel conduit is axially constrained at only a single location proximate said downstream end of said fuel plenum, such that said middle section is configured to thermally expand and contract axially without substantial structural constraint.
4. The fuel nozzle assembly of claim 3 , wherein said single location is a joint downstream from said downstream end of said fuel plenum.
5. The fuel nozzle assembly of claim 1 , wherein the third radial distance is zero.
6. The fuel nozzle assembly of claim 1 , wherein said downstream section of said liquid fuel conduit is axially constrained at only a single location proximate said downstream end of said fuel plenum, such that said downstream section is configured to thermally expand and contract axially without substantial structural constraint.
7. The fuel nozzle assembly of claim 6 , wherein said single location is a joint downstream from said downstream end of said fuel plenum.
8. The fuel nozzle assembly of claim 7 , wherein the second distance is greater than the third distance.
9. The fuel nozzle assembly of claim 1 , further comprising an aft face plate coupled to an aft end of said fuel nozzle assembly, said aft face plate defining a pilot opening, said pilot opening being in serial flow communication with said downstream section of said liquid fuel conduit via a pilot tip.
10. The fuel nozzle assembly of claim 1 , wherein the first distance is greater than the second distance.