Abstract:
A method and apparatus for cooling a combustor liner and transitions piece of a gas turbine include a combustor liner with a plurality of turbulators arranged in an array axially along a length defining a length of the combustor liner and located on an outer surface thereof; a first flow sleeve surrounding the combustor liner with a first flow annulus therebetween, the first flow sleeve having a plurality of rows of cooling holes formed about a circumference of the first flow sleeve for directing cooling air from the compressor discharge into the first flow annulus; a transition piece connected to the combustor liner and adapted to carry hot combustion gases to a stage of the turbine; a second flow sleeve surrounding the transition piece a second plurality of rows of cooling apertures for directing cooling air into a second flow annulus between the second flow sleeve and the transition piece; wherein the first plurality of cooling holes and second plurality of cooling apertures are each configured with an effective area to distribute less than 50% of compressor discharge air to the first flow sleeve and mix with cooling air from the second flow annulus.
Abstract:
A method and apparatus for cooling a combustor liner and transitions piece of a gas turbine include a combustor liner with a plurality of circular ring turbulators arranged in an array axially along a length defining a length of the combustor liner and located on an outer surface thereof; a first flow sleeve surrounding the combustor liner with a first flow annulus therebetween including a plurality of axial channels (C) extending over a portion of an aft end portion of the liner parallel to each other, the cross-sectional area of each channel either constant or varying along the length of the channel, the first flow sleeve having a plurality of rows of cooling holes formed about a circumference of the first flow sleeve for directing cooling air from the compressor discharge into the first flow annulus; a transition piece connected to the combustor liner and adapted to carry hot combustion gases to a stage of the turbine; a second flow sleeve surrounding the transition piece a second plurality of rows of cooling apertures for directing cooling air into a second flow annulus between the second flow sleeve and the transition piece; wherein the first plurality of cooling holes and second plurality of cooling apertures are each configured with an effective area to distribute less than 50% of compressor discharge air to the first flow sleeve and mix with cooling air from the second flow annulus.
Abstract:
A secondary fuel nozzle for a turbine includes a passive purge air passageway which provides purge air to the secondary nozzle at all times that the nozzle is in operation. The passive purge air passageway draws in air from a location adjacent an upstream end of the nozzle. Because of a pressure differential between air located at the downstream end of the nozzle and air located at the upstream end of the nozzle, purge air will run through the passive purge air passageway at all times the nozzle is in operation. There is no need for a supply of compressed purge air.
Abstract:
A secondary fuel nozzle for a turbine includes a passive purge air passageway which provides purge air to the secondary nozzle at all times that the nozzle is in operation. The passive purge air passageway draws in air from a location adjacent an upstream end of the nozzle. Because of a pressure differential between air located at the downstream end of the nozzle and air located at the upstream end of the nozzle, purge air will run through the passive purge air passageway at all times the nozzle is in operation. There is no need for a supply of compressed purge air.
Abstract:
A liner (18) installed in a transition region (16) between a combustion section (12) of a gas turbine engine (10) and an air discharge section (14) of the turbine. The liner has an air inlet (26) for admitting air into the liner, and an air outlet (28) by which air is discharged from the liner. Flow of air through the liner acts to cool air flowing through the transition region of the turbine between the combustion and air discharge sections thereof, so to lower the temperature from between 2800-3000° F. to around 1400-1550° F. The liner has at least one channel (C1, C2) formed in it for flow of air through the liner. The height of this channel uniformly decreases along the length of the channel from the liner's air inlet to its air outlet. This liner construction reduces the thermal strain occurring at the aft end of the liner, prolonging the useful life of the liner, while reducing the amount of air needed to flow through the liner to affect a desired level of cooling in the transition region.