GB1332679A - Turbomachinery blade structure - Google Patents

Abstract

1332679 Gas turbine blades GENERAL ELECTRIC CO 12 Nov 1970 53984/70 Heading FIT A gas turbine blade structure comprises an integrally cast hollow member 20, means 22 for mounting the blade on a rotor, and an insert 24 for directing coolant fluid within a blade portion 26 of the hollow member 20. The blade portion 26 extends from a platform portion 28 in the opposite direction to a shank portion 30. A chamber 34 within the member 20 includes a trailing edge portion 46 across which a plurality of posts 48 extend to connect the opposed side walls 40. A plurality of passages 50 are provided in the trailing edge 38 to permit efflux of coolant fluid from the chamber 34. Additional efflux passages 52 are formed in the integrally cast end closure wall 44. The insert 24 is a thinwalled shell having side walls 64 conforming to the contour of the blade side walls 40 and is provided with spacing means such as dimples 68 and a plurality of apertures 66. The insert 24 is closed at one end 70 and defines a chamber 72 which is open at the opposite end 74 to receive coolant fluid. The blade mounting means 22 comprises a root insert 92 which is bonded to the opposed inner shank surfaces (94, 96), Fig. 8 (not shown) and to the open end 74 of insert 24. Coolant inlet passages 62 extend through the root insert 92 to communicate with the chamber 72. The root insert 92 is formed with a "fir tree", dovetail, or other suitable configuration and is provided at its ends with seal plates 86. From inlet passages 62, the coolant fluid enters insert chamber 72 and is then impinged against the blade wall inner surfaces by apertures 66. The number location and size of the apertures 66 are so selected as to achieve a generally uniform side wall temperature around the periphery of the blade. From chamber 34, the coolant fluid is exhausted into the hot gas stream through end closure passages 52 and trailing edge passages 50.