Combustor wall cooling channel formed by additive manufacturing

A combustor section of a gas turbine engine comprising:

• a plurality of annular wall segments defining a cavity for combustion having a centerline extending axially through a geometric center of the cavity and defining a plurality of radial passages, wherein each of the plurality of radial passages extends through one of the plurality of annular wall segments;
• a plurality of inner wall segments spaced radially inward from the annular wall segments so as to define axial channels between each of the inner wall segments and one of the plurality of annular wall segments, wherein the axial channel is in fluid communication with at least one of the radial passages, and wherein the inner wall segments are configured to define circumferentially-extending openings between opposing end faces of adjacent inner wall segments;
• a plurality of connecting walls, each connecting wall extending from one of the plurality of annular wall segments to one of the plurality of inner wall segments;
• wherein:
• the annular outer wall segments are formed from a metallic material;
• the inner wall segments are formed from a ceramic material;
• and
• the connecting walls have a functionally graded distribution of the metallic and ceramic materials between respective annular outer wall and inner wall segments.

A method of manufacturing a cooled wall for a combustor of a gas turbine engine;

• the method comprising:
• a.) providing a three-dimensional computer model of the cooled wall;
• b.) depositing a powdered material to form a uniform thickness layer on a substrate or a previously deposited layer;
• c.) using a laser or an electron beam to melt or sinter the powdered material to form a cross-section of the cooled wall defined by the three-dimensional computer model;
• and
• d.) repeating steps b-c to form a cooled wall, wherein the cooled wall comprises:
• an annular outer wall extending axially along a centerline intersecting the geometric center of the gas turbine, wherein the annular outer wall defines a radial passage, and wherein the radial passage extends through the annular outer wall;
• a first inner wall spaced radially inward from the annular outer wall with respect to the centerline;
• a first connecting wall joining the first inner wall to the annular outer wall, wherein the annular outer wall, the first inner wall, and the first connecting wall define an axial channel therebetween that is in fluid communication with the radial passage;
• a second inner wall spaced radially inward from the annular outer wall;
• and
• a second connecting wall joining the second inner wall to the annular outer wall, wherein the second inner wall is axially spaced from the first inner wall to define a circumferentially-extending opening between a first end face of the first inner wall and a second end face of the second inner wall:
• wherein:
• the annular outer wall, the first and second inner walls, and the first and second connecting walls form a monolithic body;
• the annular outer wall is formed from a metallic material;
• the first and second inner walls are formed from a ceramic material;
• and
• the first and second connecting walls have a functionally graded distribution of the metallic and ceramic materials between the annular outer wall and the first and second inner walls, respectively.