Patent ID: 6394749
Filing Date: 2002-05-28
Classification: F01D,F05D

Abstract:
Apparatus for controlling a temperature mismatch in at least one of the inner and outer bands of a turbine including nozzles having cooling circuits for flowing a cooling medium, comprising:a nozzle segment having at least one nozzle vane and inner and outer nozzle band portions adjacent opposite ends of said nozzle vane and in part defining a path for flowing hot gases of combustion; one of said band portions forming a wall exposed to said hot gas path of said turbine and having a cover on a side of said wall remote from said hot gas path, said cover and said wall defining a plenum therebetween for receiving the cooling medium forming part of a cooling circuit; said segment including at least one passage separate from and not in communication with said plenum and extending alone and through said cover along a length of said segment from adjacent a leading edge to a trailing edge thereof for flowing a thermal medium at a temperature intermediate the temperature of the cooling medium receivable in said plenum and the hot gases of combustion to reduce the temperature differential between said cover and said wall and thereby reduce thermal-induced stresses in said one band portion.