LATTICE SUPPORTED DUAL COILED FUEL TUBES
A fuel injector for a gas turbine engine includes a fuel inlet fitting for receiving fuel, with a feed arm mounted to the inlet. The feed arm has a lattice support structure. The lattice support structure may include a plurality of three-dimensional elements, a first conduit, and a second conduit in fluid communication with the inlet for conveying fuel from the inlet fitting through the feed arm, wherein the conduits are intertwined with each other, and a nozzle body operatively connected to the feed arm for injecting fuel from the conduits into a combustor of the gas turbine engine.
1 . A fuel injector for a gas turbine engine comprising:
an inlet having a fuel inlet fitting for receiving fuel;
a feed arm mounted to the inlet, wherein the feed arm includes a lattice support structure, the lattice support structure including a plurality of three-dimensional elements, a first conduit and a second conduit in fluid communication with the inlet for conveying fuel from the inlet fitting through the feed arm, wherein the conduits are intertwined with each other; and
a nozzle body operatively connected to the feed arm for injecting fuel from the conduits into a combustor of a gas turbine engine.
2 . A fuel injector as recited in claim 1 , wherein the lattice support structure is continuous.
3 . A fuel injector as recited in claim 1 , wherein the lattice support structure is mostly hollow.
4 . A fuel injector as recited in claim 1 , wherein three-dimensional elements of the lattice support structure wrap around both of the conduits at multiple locations.
5 . A fuel injector as recited in claim 1 , wherein the conduits are joined to the three-dimensional elements of the continuous lattice at multiple locations.
6 . A fuel injector as recited in claim 1 , wherein the conduits form a double helix structure.
7 . A fuel injector as recited in claim 1 , wherein the first conduit has a larger diameter than the diameter of the second conduit.
8 . A fuel injector as recited in claim 1 , wherein the three-dimensional elements of the continuous lattice have a diameter smaller than the diameter of the first conduit.
9 . A fuel injector as recited in claim 1 , wherein the conduits are surrounded at least in part by an enclosure.
10 . A fuel injector as recited in claim 9 , wherein the conduits are joined to the enclosure at multiple locations, and the three-dimensional elements of the continuous lattice are joined to the enclosure at multiple locations.
11 . A fuel injector as recited in claim 10 , wherein the two conduits form a double helix structure, and the first conduit has a larger diameter than the second conduit.
12 . A fuel injector as recited in claim 1 , wherein the lattice support structure provides a conduit configured for passing gaseous fuel from the inlet to the nozzle body.
13 . A fuel injector as recited in claim 1 , wherein the conduits are surrounded at least in part by an exterior heat shield, which thermally insolates the conduits from external conditions.
14 . A fuel injector as recited in claim 13 , wherein the conduits are surrounded at least in part by an enclosure, the enclosure being separated from the heat shield by a gap, and the three-dimensional elements of the continuous lattice are joined to the enclosure at multiple locations.
15 . A fuel injector as recited in claim 1 , wherein the conduits have wall thicknesses between 0.008 and 0.015 inches.
16 . A fuel injector as recited in claim 1 , wherein the conduits merge into a single conduit at a first end or a second end.
17 . A fuel injector as recited in claim 1 , wherein the lattice support structure includes a material suitable for processing by at least one process selected from the group consisting of direct metal laser sintering, selective laser sintering, and electron beam melting.
18 . A fuel injector as recited in claim 1 , wherein the feed arm includes an integral mounting flange.
19 . A fuel injector as recited in claim 1 , wherein the feed arm is formed by an additive fabrication process.