Effusion momentum control

A combustor liner suitable for use in a turbine engine, said combustor liner comprising:

• a nonplanar inner liner;
• a nonplanar outer liner;
• and
• a liner dome attached to said inner liner and to said outer liner so as to form an assembly enclosing a combustion zone, said liner dome having an exterior cool surface for intercepting a cooling air stream and an interior hot surface, said liner dome further having an array of effusion holes therethrough for passing cooling air from said cooling air stream into said combustion zone, wherein a local region of said array of effusion holes includes a plurality of upstream-pointed effusion holes, said upstream-pointed effusion holes having orientations obtuse to the direction of a main flow of gases in said combustion zone.

A combustor liner suitable for shielding an engine from heat generated in a combustion zone, said combustor liner comprising:

• a liner dome having a cool surface for intercepting a cooling air stream and a hot surface partially enclosing the combustion zone, said liner dome further having an array of dome effusion holes therethrough, each of said dome effusion holes extending from said cool surface to said hot surface so as to allow a portion of said cooling air stream to pass through said plurality of dome effusion holes into the combustion zone, wherein a local region of said array of dome effusion holes includes a plurality of downstream-pointed dome effusion holes and a plurality of upstream-pointed dome effusion holes, said plurality of downstream-pointed dome effusion holes oriented such that each said downstream-pointed dome effusion hole has a longitudinal axis generally in the direction of a main flow in the combustion zone, and each said upstream-pointed dome effusion hole has a longitudinal axis forming an obtuse angle with the direction of said main flow such that cooling air entering the combustion zone through said upstream-pointed dome effusion holes reduces the momentum of cooling air entering the combustion zone through said downstream-pointed dome effusion holes;
• a nonplanar inner liner partially enclosing the combustion zone and attached to said liner dome, said inner liner having a plurality of inner liner downstream-pointed effusion holes and a plurality of inner liner upstream-pointed effusion holes therethrough;
• and
• a nonplanar outer liner partially enclosing the combustion zone and attached to said liner dome, said outer liner having a plurality of outer liner downstream-pointed effusion holes and a plurality of outer liner upstream-pointed effusion holes therethrough.

A method of making a combustor liner for increasing cooling efficiency, said combustor liner having an initial array of effusion holes, said method comprising the steps of:

• selecting a local region of said initial array of effusion holes for analysis;
• denoting a fraction of the effusion holes in said local region as upstream-pointed effusion holes so as to provide a revised effusion hole configuration;
• specifying an obtuse orientation angle for each of said upstream-pointed effusion holes in said revised effusion hole configuration such that said upstream-pointed effusion holes are oriented at said obtuse orientation angle to a main flow direction in the combustor liner;
• analyzing the resulting effusion hole configuration to produce temperature distribution data quantifying cooling efficiency at an interior surface of said combustor liner;
• and
• if said temperature distribution data are not within a desired range, repeating said steps of denoting a fraction, specifying an obtuse orientation angle, and analyzing the resulting array to obtain a satisfactory effusion hole configuration.