BACKGROUND

This disclosure relates to a combustor for a gas turbine engine and, more particularly, to flow distribution through a combustor liner of the combustor.

Gas turbine engines can include a fan for propulsion air and to cool components. The fan also delivers air into a core engine where it is compressed. The compressed air is then delivered into a combustor section.

The combustor section includes one or more combustor liners that define a combustion chamber. Fuel is ejected from fuel injectors into the combustion chamber. The compressed air is mixed with the fuel and ignited in the combustion chamber to produce relatively hot combustion gases. The combustion gases expand downstream over and drive turbine blades.

The combustor liners are subject to extreme heat due to the combustion process. Formation of hot spots can occur along localized regions of the combustor liners. Cooling flow may be utilized to cool portions of the combustor liners at locations adjacent to the hot spots.

SUMMARY

A combustor liner for a gas turbine engine according to an example of the present disclosure includes at least one liner segment that has an external wall dimensioned to bound a combustion chamber. The external wall extends between leading and trailing edges in an axial direction and extends between opposed mate faces in a circumferential direction. A cooling circuit is defined by the external wall. A plurality of heat transfer features are distributed in the cooling circuit to define a first restricted flow region that tapers from the leading edge to the trailing edge and to define at least one prioritized flow region that extends substantially from the leading edge to the trailing edge such that the at least one prioritized flow region is bounded by a perimeter of the first restricted flow region, and the at least one prioritized flow region has a lesser concentration of the plurality of heat transfer features than the first restricted flow region.

In a further embodiment of any of the foregoing embodiments, the at least one prioritized flow region includes first and second prioritized flow regions on opposed sides of the first restricted flow region.

In a further embodiment of any of the foregoing embodiments, the plurality of heat transfer features are distributed in the cooling circuit to define second and third restricted flow regions that extend substantially along the mate faces to bound respective ones of the first and second prioritized flow regions.

In a further embodiment of any of the foregoing embodiments, each of the first and second prioritized flow regions has a substantially trapezoidal geometry.

In a further embodiment of any of the foregoing embodiments, the at least one liner segment includes a first liner segment and a second liner segment arranged in the axial direction to define a stepwise change in area of the combustion chamber such that the cooling circuit of the first liner segment is oriented to eject cooling flow from the trailing edge of the first liner segment onto external surfaces of the external wall of the second liner segment that defines the combustion chamber.

In a further embodiment of any of the foregoing embodiments, the at least one liner segment includes an array of liner segments, and each of the mate faces defines an intersegment gap with an adjacent one of the liner segments.

In a further embodiment of any of the foregoing embodiments, the plurality of heat transfer features includes a plurality of pedestals that extend in a radial direction between opposed internal surfaces defining the cooling circuit.

In a further embodiment of any of the foregoing embodiments, respective sets of the plurality of heat transfer features are uniformly distributed in the first restricted flow region and in the at least one prioritized flow region.

A further embodiment of any of the foregoing embodiments includes a thermal barrier coating disposed on surfaces of the external wall defining the combustion chamber.

In a further embodiment of any of the foregoing embodiments, the surfaces of the external wall defining the combustion chamber are substantially free of any cooling apertures along the cooling circuit.

In a further embodiment of any of the foregoing embodiments, the external wall is a bulkhead that bounds the combustion chamber in the axial direction. The bulkhead has at least one aperture along the combustion chamber that is dimensioned to receive a fuel injector nozzle.

A combustor section for a gas turbine engine according to an example of the present disclosure includes an array of fuel injector nozzles arranged about a longitudinal axis. A combustor liner includes an array of liner segments arranged about the longitudinal axis to define a combustion chamber. Each one of the fuel injector nozzles defines a nozzle axis. A projection of the nozzle axis extends through the combustion chamber. Each one of the liner segments includes an external wall extending axially between leading and trailing edges and extending circumferentially between opposed mate faces with respect to the longitudinal axis. A cooling circuit is defined by the external wall. A plurality of heat transfer features are distributed in the cooling circuit to define first and second prioritized flow regions on opposed sides of a first restricted flow region. Each of the first and second prioritized flow regions extend axially along the projection of the nozzle axis of respective ones of the fuel injector nozzles from the leading edge to the trailing edge such that the first restricted flow region tapers from the leading edge to the trailing edge, and each of the first and second prioritized flow regions have a relatively greater average flow path volume than the first restricted flow region.

In a further embodiment of any of the foregoing embodiments, the plurality of heat transfer features are distributed in the cooling circuit to define second and third restricted flow regions that extend substantially along the mate faces to bound a perimeter of respective ones of the first and second prioritized flow regions, and each of the first and second prioritized flow regions has a relatively greater average flow path volume than the second and third restricted flow regions.

In a further embodiment of any of the foregoing embodiments, surfaces of the external wall defining the combustion chamber are substantially free of any cooling apertures along the cooling circuit.

A gas turbine engine according to an example of the present disclosure includes a compressor section, a turbine section that drives the compressor section, a combustor section has a combustor. The combustor has a combustor liner and an array of fuel injector nozzles arranged about an engine longitudinal axis. The combustor liner has an array of liner segments arranged about the engine longitudinal axis to define a combustion chamber. Each one of the fuel injector nozzles defines a nozzle axis. A projection of the nozzle axis extends through the combustion chamber. Each one of the liner segments includes an external wall extending axially between leading and trailing edges and extending circumferentially between opposed mate faces with respect to the engine longitudinal axis. A cooling circuit is defined by the external wall. A plurality of heat transfer features are distributed in the cooling circuit to define first and second prioritized flow regions on opposed sides of a first restricted flow region. Each of the first and second prioritized flow regions extend axially along the projection of the nozzle axis of respective ones of the fuel injector nozzles such that a width of the first and second prioritized flow regions progressively increases from the leading edge to the trailing edge.

In a further embodiment of any of the foregoing embodiments, the first restricted flow region is circumferentially spaced from the projection of the nozzle axis of each and every one of the fuel injector nozzles.

In a further embodiment of any of the foregoing embodiments, the first restricted flow region tapers from the leading edge to the trailing edge.

In a further embodiment of any of the foregoing embodiments each of the mate faces defines an intersegment gap with the mate face of an adjacent one of the liner segments. The plurality of heat transfer features are distributed in the cooling circuit to define second and third restricted flow regions that extend substantially along the mate faces to bound a perimeter of respective ones of the first and second prioritized flow regions.

In a further embodiment of any of the foregoing embodiments, the intersegment gap is dimensioned to eject cooling flow into the combustion chamber.

In a further embodiment of any of the foregoing embodiments, the array of liner segments includes a first set of liner segments and a second set of liner segments axially arranged to define a stepwise change in area of the combustion chamber such that each cooling circuit of the first set of liner segments is oriented to eject cooling flow onto external surfaces of the second set of liner segments bounding the combustion chamber.

The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of an embodiment. The drawings that accompany the detailed description can be briefly described as follows.

