Patent GB-767177-A (GB)
Title: Improvements in or relating to gas turbine power plant arrangements
Inventor: JOHNSON CHRISTOPHER LINLEY
IPC: F02C7/047
Filed: 1952-10-10
Abstract: 767,177. Gas turbine plant. ROLLS-ROYCE, Ltd. Oct. 5, 1953 [Oct. 10, 1952], No. 1154/56. Divided out of 767,176. Class 110 (3). A gas turbine power plant comprising means for tapping air heated by compression, heating means to produce from the power plant hot gas at a temperature above the temperature of the air abstracted from the compressor and a conduit through which the air and hot gas are led to de-icing means has valve means to control the individual flows of air and hot gas controlled by temperature-sensitive means responsive only to the temperature of the heated gas and a relief valve located in the delivery conduit preset to a selected pressure so as to control the quantity of heat transmitted to the parts to be de-iced. Compressed air is bled from the compressor 10 supplying combustion air to the combustion chambers 12 of a gas turbine plant through a port 22 and a conduit 23 controlled by a butterfly valve 24. Combustion products are bled from the combustion chambers 12 through porting 25 and a conduit 26 controlled by a butterfly valve 27 and are mixed with the bled air and passed through a delivery conduit 28 to a manifold 18 surrounding the compressor intake. The hot gas-air mixture then passes through hollow struts 16 to a chamber 20 in the bearing housing 17 and from there pass into the nose fairing 15 where it is discharged into the air stream entering the compressor through ports 21. The size of the ports 21 are chosen to limit the maximum flow. The butterfly valves 24, 27 are coupled together for simultaneous operation and are controlled by temperature responsive means 43 responsive to the temperature in the discharge conduit 28. The operating arms of the valves 24, 27 are connected to the operating rod 32 actuated by a motor 31 in such a manner that when the valve 27 is fully open the valve 24 is closed. As the rod 32 moves to the left with increasing temperature in the conduit 28, the valve 27 is gradually closed and the valve 24 opened until the valve 27 is fully closed and the valve 24 fully open. A further increase in temperature closes the valve 24 again and a lost motion connection between the operating rod 32 and the valve 27 allows the valve 27 to be maintained in the fully closed position. A pressure-limiting means such as relief valve 53 is provided to prevent excessive pressure in the conduit 28. The temperature responsive means 43 may be a bi-metallic strip which operates the valves 24, 27 directly or energizes an electrical circuit controlling the valves. In a modification air is bled from the compressor discharge and heated by the turbine exhaust gases in a heat exchanger which may be formed by the surface of the exhaust bullet or located outside the jet pipe. This heated air is mixed with further air from the compresser before passing to the conduit 28. In another modification the hot gas is extracted from the turbine exhaust and the valves 24, 27 are replaced by a single valve at the junction of the conduits 23, 26 so that it can close or partially close these conduits. The control of this valve may be arranged to operate gradually over a range of temperatures or to operate at a selected temperature so that the conduit 28 is supplied wholly from the compressor or the turbine exhaust. A manually operated override valve or valves may be provided to shut off the flow of gas to the anti-icing means. Specifications 578,769 and 697,093 are referred to. Reference has been directed by the Comptroller to Specification 709,547.