Patent attributes
A fuel injector for gas turbine engines includes an inlet fitting, a housing stem, and a spray nozzle. A pair of fuel passages in the stem deliver fuel in a primary (continuous) flow and a secondary (non-continuous or reduced) flow to primary and secondary discharge orifices in the nozzle. The fuel passages are defined by inner and outer concentric conduits, with the primary flow directed through the inner conduit, and the secondary flow directed through the outer conduit. Fins are provided unitary with the inner conduit along the length of the housing stem, and are fixed at their radial outer ends to the outer conduit. The fins provide structural support and thermally connect the inner and outer conduits. During low power operation, the fins transfer heat energy between the outer conduit to the inner conduit to cool the outer conduit and thermally protect the fuel in the secondary fuel passage.