Patent GB-920887-A (GB)
Title: Improvements in or relating to gas-turbine engines
Inventor: KENT NELSON HECTOR
IPC: F01D11/04
Filed: 1958-11-24
Abstract: 920,887. Jet propulsion engines. ROLLS-ROYCE Ltd. Oct. 26, 1959 [Nov. 24, 1958] No. 37823/58. Class 110 (3). In a gas turbine engine of the type comprising a ducted fan which encircles the turbine and has rotor blades formed as extensions of the turbine blades, the stationary and rotating parts of the structure separating the turbine and ducted fan are constructed to form an air flow path from an inlet adjacent the ducted fan inlet to discharge means downstream of the ducted fan blades, so that air flows across the clearance spaces between the rotating and stationary parts and entrains hot gas leaking from the working fluid duct of the turbine and carries it to discharge means. The ducted fan and its turbine are mounted on a shaft 21 which has a flange 21a on which a first rotor disc 24 is mounted and a second rotor disc 25 is secured to the end of the shaft. Each disc carries a row of blades and platform portions 27e, 28e thereon form parts of the working fluid ducts. A bullet member 29 is secured to the downstream face of the disc 25. Hollow interstage guide vanes 36 are divided internally to form flow passages 39, 40. The inner ends of the vanes are secured to an annular bearing housing structure 38 and the outer ends to an annular wall structure 34. Structur 34 comprises annular walls 41, 42, 43, end walls 44, 45 and a flanged ring 46 forming a manifold connecting the passages 39 through radial tubes 48 with hollow inlet guide vanes 31. The upstream end of the wall 42 forms an air entry leading to ports 52 in a manifold 53 which has outlet ports 54 in the walls 45. To prevent the turbine gases passing into the ducted fan, air from intake 42a passes through holes 52, 54 into the spaces formed between platforms 27e. The air is directed through holes 74 to the space between platforms 28e, through hollow vane 33 to a manifold 67 and is exhausted through hole 75. The wall structure 34 also has ports 50, in the wall 41, joining the passages 40 with a manifold 51 which is fed with compressed air. High pressure air from the manifold 51 flows through the passages 40 and elbow tubes 55 into space 56 and a part leaks past the outer seal 57 into a space 59 to prevent inward flow of gas from the turbine first stage. The remainder of the air flows through tubes 80 past seal 82 to seal the inner ends of the blades 27b and through seal 83, holes 84, space 85, and channels 86 into space 87, from which space the air flows through holes 88 to provide sealing air for the seal on the sleeve 62 at the inner ends of the guide vanes 37. From space 81, high pressure air also passes into spaces 81a into radial passages 27f, 27g thereby cooling the turbine blades 27b and heating the ducted fan blades 27d. Low pressure air from the interior of shaft 21 flows through holes 76, spaces 77 and holes 78 into an annular chamber 79 then through the passages 39 thereby cooling vanes 36. The heated air flows through ports 47 into the inlet guide vanes 31 to heat them and into a chamber 65 in the outer casing 30. From the chamber 65 the air is exhausted via holes 69, chamber 66 and holes 70. Specification 920,886 is referred to.