Transition-to turbine seal apparatus and transition-to-turbine seal junction of a gas turbine engine

One embodiment of a transition-to-turbine seal ( 320 ) comprises an upstream portion ( 322 ) adapted to engage a flange ( 416 ) of a transition ( 400 ). The upstream portion ( 322 ) may be U-shaped in cross-sectional profile and comprises a primary wall ( 324 ) that comprises a proximal section ( 325 ) and a distal section ( 326 ) relative to a hot gas path ( 170 ). The proximal section ( 325 ) comprises a plurality of recesses ( 327 ) which are spaced apart and separated by intervening wall ( 328 ). In each recess ( 327 ) is provided one or more outlets ( 329 ) of cooling fluid holes ( 339 ). The outlets ( 329 ) communicate via the cooling fluid holes ( 339 ) with a supply of compressed cooling fluid, such as compressed air that is provided from the compressor. During operation the outlets ( 329 ) release this fluid into the respective recesses ( 327 ). The flow of cooling fluid through such outlets ( 329 ) in the respective recesses ( 327 ) provides for a more uniform cooling effect that includes impingement and convective cooling. Further, the outlets and recesses reduce the likelihood of hot gas ingestion due to local pressure gradients. Toward its downstream end, the seal ( 320 ) also comprises a downstream groove ( 321 ) which is adapted to engage a lip ( 138, 139 ) of a row 1 vane segment ( 130 ). Variations of the transition-to-turbine seal are described.