GB736503A - Improvements relating to gas-turbine engines - Google Patents

Abstract

736,503. Gas turbine plant. ROLLS. ROYCE, Ltd. Sept. 10, 1953 [June 12, 1952], No. 14886/52. Class 110 (3). In a gas turbine engine, air is tapped off from the compressor and conveyed through ducting including hollow stator blades at the compressor inlet to hollow rotor shafting which extends from adjacent the compressor inlet to adjacent the turbine and conveys the air to the turbine for cooling or sealing purposes, the rate of flow of air through the hollow stator blades permitting a dissipation of heat from the air at least sufficient to preventing icing of those blades. The tapped-off air is thus cooled before being conveyed to the turbine. Air is tapped off from the delivery end of the compressor and conveyed forwardly through pipes 36, Fig. 3, to an annular manifold 37 and thence through hollow inlet guide vanes 12 to a chamber 38, from which it flows through the hollow compressor shaft 16 and the hollow turbine shaft 24, Fig. 2, to the turbine. Part of the air flows out through drillings 39 in the first turbine rotor disc 30 into a space 40 to cool the disc 30 and a diaphragm 28 and thence through a labyrinth seal 41 and a gap 42 into the working fluid passage of the turbine. Another part of the air flows through drillings 43, a space 44 between the two discs 30, further drillings 45, a labyrinth seal 47 and gaps 49. A further part of the air flows from an outlet 50 and through the space 51 between the second disc 30 and the base 33a of the exhaust cone. The turbine shaft may be supported by a bearing provided in the exhaust cone ; this bearing may be cooled by air supplied from the hollow shaft. Under icing conditions, an increased quantity of tapped-off air is passed through the hollow vanes 12, some of the additional air being passed through a valve 53 into the intake bullet 14 of the engine to heat the bullet, and leaving the bullet through holes therein. The remainder of the additional air passes through ports 55 under the control of a valve 56 to the inner ends of hollow rotor blades 18a which are provided with outlets as shown. Valves 53 and 56 may be connected by a bearing 57 for joint operation, as by a solenoid.