GB767176A - Improvements in or relating to gas turbine power plant arrangements - Google Patents

Abstract

767,176. Gas turbine plant. ROLLS-ROYCE, Ltd. Oct. 5,1953 [Oct. 10, 1952], No. 25509/52. 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 means to control the flow of air and hot gas controlled by temperature responsive means responsive to the temperature of a part on which ice is liable to form to increase the flow of hot gas from the heating means into the conduit when the temperature sensed by the temperature responsive means falls below a selected value. 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 a 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 now. The butterfly valves 24, 27 are coupled together for simultaneous operation and are controlled by temperature-responsive means 29 arranged to sense the temperature of the strut 16. The operating arms of the valve 24, 27 are connected to an 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 at the strut 16, 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. In a modification, the hot gas is extracted from the turbine exhaust, and the butterfly valves 24, 27 are replaced by a single valve at the junction of the conduits 23 26 so that it can close wholly or partially the 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 conduit 28 is supplied wholly from the compressor or from the turbine exhaust. In another 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 around the jet pipe. This heated air is mixed with further air from the compressor before passing to the conduit 28. In a further modification, Fig. 5, the valves 24 and 27 are controlled by temperatureresponsive means 43 sensitive to the temperature of the gases in the conduit 28. A further temperature-responsive means 45 on the strut 16 controls a throttle valve 44. The valve 44 may be hand operated and the valves 24, 27 controlled by temperature-responsive means 29. A manually-operated override valve or valves may be provided to shut off the flow of gas to the anti-icing means. The features of some of the modifications may be embodied in others. Specifications 578,769 and 697,093 are referred to. Reference has been directed by the Comptroller to Specification 709,547.