COMBUSTOR LINER COOLING AT TRANSITION DUCT INTERFACE AND RELATED METHOD

A combustor assembly for a turbine includes a combustor and a combustor liner (54); a first flow sleeve (62) surrounding the combustor liner forming a first substantially axially-extending flow annulus (64) radially therebetween. The first flow sleeve (62) has a first plurality of apertures (28) formed about a circumference thereof for directing compressor discharge air as cooling air radially into the first flow annulus. A transition (52) is piece connected to the combustor liner (54), the transition piece adapted to carry hot combustion gases to the turbine, and a second flow sleeve (58) surrounds the transition piece forming a second substantially axially-extending flow annulus (60) radially therebetween. The second flow sleeve has a second plurality of apertures for directing compressor discharge air as cooling air radially into the second flow annulus (60), the first substantially axially-extending flow annulus (64) connecting with the second substantially axially-extending flow annulus (60). A resilient annular seal structure (86) is disposed radially between an aft end portion (56) of the combustor liner and a forward end portion (92) of the transition piece, the resilient annular seal structure configured to form a first annular cavity (104) radially between the forward end portion of the transition piece and the aft end portion of the combustor liner. At least one transfer tube (100) extends radially from the second flow sleeve (58) through the second flow annulus (60) to the transition piece (52), and is arranged to supply compressor discharge cooling air radially from an area outside the first and second substantially axially-extending flow annuli (64, 60) directly to the resilient annular seal structure (86) and to the aft end (92) of the combustor liner.