A conjoined grommet assembly for a combustor wall assembly of a gas turbine engine has a first grommet defining at least in-part a first dilution hole, and a second grommet defining at least in-part a second dilution hole. The first and second dilution holes are spaced closely together such that the first grommet is in contact with the second grommet.

A flexible seal is used to seal between two adjacent gas turbine components. The flexible seal includes at least one metal ply having a forward end, an aft end axially separated from the forward end, and an intermediate portion between the forward end and the aft end. The intermediate portion defines a continuous curve in the circumferential direction, such that the aft end is circumferentially, and optionally radially, offset from the forward end. A plurality of relief cuts is defined through the at least one metal ply between the forward end and the aft end to increase flexibility and improve sealing in seal slots that are radially offset from one another.

A flexible seal is used to seal between two adjacent gas turbine components. The flexible seal includes at least one metal ply having a forward end, an aft end axially separated from the forward end, and an intermediate portion between the forward end and the aft end. The intermediate portion defines a continuous curve in the circumferential direction, such that the aft end is circumferentially, and optionally radially, offset from the forward end. A plurality of relief cuts is defined through the at least one metal ply between the forward end and the aft end to increase flexibility and improve sealing in seal slots that are radially offset from one another.

A system includes an internal manifold ring defining at least one circumferentially extending flow channel. A plurality of feed arms extends outward from the manifold ring. A circumferentially segmented outer ring can be supported from the feed arms, outboard of the feed arms. Each feed arm can include a plurality of branches extending therefrom, wherein each branch is in fluid communication with the manifold ring through a respective one of the feed arms. A plurality of nozzles can be included, each nozzle connected to a respective one of the branches, wherein the system is devoid of nozzles radially inward from the manifold ring.

A system includes an internal manifold ring defining at least one circumferentially extending flow channel. A plurality of feed arms extends outward from the manifold ring. A circumferentially segmented outer ring can be supported from the feed arms, outboard of the feed arms. Each feed arm can include a plurality of branches extending therefrom, wherein each branch is in fluid communication with the manifold ring through a respective one of the feed arms. A plurality of nozzles can be included, each nozzle connected to a respective one of the branches, wherein the system is devoid of nozzles radially inward from the manifold ring.

A substrate having one or more shaped effusion cooling holes formed therein. Each shaped cooling hole has a bore angled relative to an exit surface of the combustor liner. One end of the bore is an inlet formed in an inlet surface of the combustor liner. The other end of the bore is an outlet formed in the exit surface of the combustor liner. The outlet has a shaped portion that expands in only one dimension. Also methods for making the shaped cooling holes.

A substrate having one or more shaped effusion cooling holes formed therein. Each shaped cooling hole has a bore angled relative to an exit surface of the combustor liner. One end of the bore is an inlet formed in an inlet surface of the combustor liner. The other end of the bore is an outlet formed in the exit surface of the combustor liner. The outlet has a shaped portion that expands in only one dimension. Also methods for making the shaped cooling holes.

Method and computer-readable model for additively manufacturing a ducting arrangement in a combustion system of a gas turbine engine are provided. The ducting arrangement may be formed by duct segments (32) circumferentially adjoined with one another to form a flow duct structure (e.g., a flow-accelerating structure (34)) and a pre-mixing structure (35). The flow duct structure may be fluidly coupled to pass a cross-flow of combustion gases. The pre-mixing structure (35) may include an array of pre-mixing tubes (48) fluidly coupled to receive air and fuel conveyed by a manifold (42) to inject a mixture of air and fuel into the cross-flow of combustion gases that passes through the flow duct structure. The duct segments or the entire ducting arrangement may be formed as a unitized structure, such as a single piece using a rapid manufacturing technology, such as 3D Printing/Additive Manufacturing (AM) technology.

A grommet may define a dilution hole in a combustor panel. The grommet may comprise a ridge having a stepped geometry formed about an inner diameter of the grommet, the ridge comprising a passage. The passage may comprise an outlet. The ridge may further comprise a fillet about the inner diameter of the grommet, wherein the outlet is configured to direct a cooling flow circumferentially along the fillet and fill the ridge with the cooling flow.

A grommet may define a dilution hole in a combustor panel. The grommet may comprise a ridge having a stepped geometry formed about an inner diameter of the grommet, the ridge comprising a passage. The passage may comprise an outlet. The ridge may further comprise a fillet about the inner diameter of the grommet, wherein the outlet is configured to direct a cooling flow circumferentially along the fillet and fill the ridge with the cooling flow.