| 摘要 |
960,071. Gas turbine blades. ROLLS-ROYCE Ltd. Aug. 24, 1962 [Aug. 30, 1961], No. 31272/61. Heading FIT. A gas turbine blade has internally thereof a first radially extending cooling duct communicating through a second chordwise duct, having walls in direct heat exchange relationship with the adjacent external walls of the blade and in which a major pressure drop occurs, with a third duct extending adjacent a radial edge of the blade and having at least one outlet for the cooling fluid, the arrangement being such that fluid from the second duct impinges on the wall of the third duct. A gas turbine rotor blade 8 has first cooling ducts in the form of passageways 11, 12 communicating with second ducts 13, 14, having a radial dimension which is equivalent to at least one third of the radial extent of the working portion of the blade, and third ducts 15, 16. Passageways 11, 12 are open at the root at ports 23, 24 but are plugged at the tip of the blade by plugs 26, 27 having bleed holes 29, 30, while passageways 15, 16 are open at both ends. Holes 34 assist cooling of the trailing edge of the blade 8. Relative sizes of the passageways are given such that a major pressure drop occurs in the passageways 13, 14, which may be replaced by a series of radially spaced holes. Additional apertures for the escape of cooling fluid may be provided in ducts 11, 12 and 15. The passageways may be formed by electro-machining the radial passageways, cutting away the leading and trailing edges of the blade, machining the chordwise passageways and then electron beam welding a cap over the cut away portions. |
