Cooled fuel injector system for a gas turbine engine
A cooling system for a fuel injector system of a gas turbine engine has a heat exchanger for cooling a portion of diffuser case air and then routing the cooled diffuser case air through a sleeve that surrounds a fuel injector conduit located in at least the diffuser case plenum for minimizing fuel heat-up rates in the conduit. By minimizing fuel temperatures within the injector conduit, coking accumulation is thereby eliminated or reduced.
1. A cooling system for a fuel injector system of a combustor section of a gas turbine engine, the cooling system comprising:
a heat exchanger for cooling hot diffuser case air;
a cooling fluid sleeve surrounding at least in part a fuel conduit of a fuel injector and extending to about a tip of the fuel injector of the fuel injector system;
an outlet of the sleeve proximate to the tip;
an inlet of the sleeve for receiving cooled diffuser case air; and
a distribution apparatus constructed and arranged to receive the cooled diffuser case air from the outlet and direct the cooled diffuser case air onto a backside of at least one heat shield of a bulkhead assembly of the combustor section.
2. The cooling system of claim 1 , wherein the distribution apparatus has a plurality of tubes spaced circumferentially from one another and about the tip.
3. The cooling system of claim 1 , wherein the distribution apparatus has an expansion joint for connection to the cooling fluid sleeve.
4. The cooling system of claim 1 , wherein the heat exchanger is configured for conditioning the cooled diffuser case air.
5. The cooling system of claim 4 wherein the heat exchanger is constructed and arranged to receive bypass air of the gas turbine engine for cooling of the diffuser case air.