GB877127A - Gas turbines - Google Patents

Abstract

877,127. Gas turbines. NAPIER & SON Ltd., D. April 7, 1960 [April 15, 1959], No. 12855/59. Class 110 (3). In a gas turbine in which the rotor is in the form of a disc 23 and there is at least one passage 29 partly bounded by the rotor disc and through which a coolant is caused to flow, a temperature-sensing device is disposed in the said passage near the periphery of the rotor disc in a position where a flow of hot turbine gases in contact with the device will occur on interruption in the flow of coolant. The invention is shown applied in the case of a gas turbine engine in which the turbine 23, 24 is a separate power turbine and cooling fluid such as air tapped from the engine compressor is supplied to the space 29 between the downstream face of the rotor disc 23 and the casing wall 28 through a series of inlets 30, the cooling fluid finally discharging through the annular gap 31 into the exhaust duct 22. The temperature-sensing device is in the form of a thermocouple 34 contained in a tube 35, the junction 37 being disposed within a perforated thimble 38 and located within the space 29. The thimble 38 protects the junction 37 from direct radiation from the rotor disc while the perforations 39 permit coolant fluid to flow in contact with the junction. A rise in temperature in the space 29 due to failure of the coolant supply is sensed by the thermocouple which actuates either a warning device or a device to reduce or cut off the fuel supply to the combustion equipment.