GB776732A - Improvements relating to turbine rotor assemblies - Google Patents

Abstract

776,732. Gas turbines; liquid seals. GENERAL MOTORS CORPORATION. Nov. 9, 1955, No. 32022/55. Classes 110 (3) and 122 (5). A gas turbine rotor assembly comprises blades having internal coolant chambers, an annular coolant chamber concentric with the rotor, and tubes connecting the blade chambers with the annular chamber, whereby liquid coolant supplied to the annular chamber is distributed centrifugally to the blade chambers where it vaporizes. Water or other liquid coolant is passed through a conduit 24, Figs. 1, 2 and 4, and a rotary slinger 58 to an auxiliary wheel 56 mounted on the shaft of the turbine rotor 52, and thence through longitudinal passages 70 and radial passages 68 to an annular chamber 66 at the rim of the wheel 56. The coolant is transferred from the chamber 66 to the interiors of hollow rotor blades 54 by way of tubes 76, Figs. 2 and 6, which fit into skewed grooves 80 milled in the rear face of the wheel 56. Inlet holes 83 in the tubes 76 align with discharge holes 82 in the wheel 56. The tubes 76 are closed by plugs 78 which fit into an annular The coolant vaporized within the blades is displaced by the heavier incoming liquid coolant towards the centre of the wheel 56, and passes by way of a passage 14<SP>1</SP>, bellows 172 and 176 and a conduit 20 to a condenser 22, where it is cooled by, say, atmospheric air supplied by the ram effect of the motion of the aircraft. The condensed coolant is returned to the conduit 24 by a pump 108. The radial depth of the ring of liquid coolant in the chamber 66 is automatically maintained within limits by a valve 112 which is opened by a solenoid 128 and closed by a solenoid 120. A detent 124 holds the valve in either position. The solenoids are operated through relays 100 and 104 by the completion, by the electrically conductive liquid coolant, of circuits including depth-sensing electrodes 92, 94, Fig. 10. A valve 110, set manually to deliver less coolant than required, supplements the valve 112. Some of the coolant is fed through a conduit 138 to the annular space between a stationary disc 142 and a rotating member 140, to act as a sealing liquid. Blades 148 may be provided to ensure rotation of the sealing liquid. Excess sealing liquid is carried away with the vaporized coolant in the conduit 20. Cooling air from, say, the plant compressor is supplied through a conduit 48 to a cylindrical casing 40, and passes through the clearance between a disc 44 and the hub of the wheel 56 to flow over the rear face of the wheel.