Patent ID: 8281594

Claim:
A fuel injector for use in a combustor apparatus of a gas turbine engine, the fuel injector extending radially inward through an opening formed in a liner and into an inner volume of the liner downstream from a main combustion zone, the fuel injector comprising: an outer wall defining an interior volume therein and including at least one opening formed therein, at least a portion of said outer wall located in the inner volume of the liner; an intermediate wall disposed in said outer wall interior volume and spaced from said outer wall such that a first gap is formed between said outer wall and said intermediate wall, said intermediate wall defining an internal volume and including at least one aperture formed therein; an inner wall disposed in said intermediate wall internal volume and spaced from said intermediate wall such that a second gap is formed between said intermediate wall and said inner wall, said second gap receiving cooling fluid that cools the fuel injector, said inner wall defining a passageway therein that receives fuel and delivers said fuel to the inner volume of the liner downstream from the main combustion zone defined by the liner; and wherein said cooling fluid in said second gap: provides convective cooling to said intermediate wall as said cooling fluid flows within said second gap; flows through said at least one aperture in said intermediate wall into said first gap where said cooling fluid provides impingement cooling to said outer wall and provides convective cooling to said outer wall as it said cooling fluid flows within said first gap; and passes into the inner volume of the liner via said at least one opening in said outer wall.