GB798617A - Improvements in aircraft propulsion - Google Patents

Abstract

798,617. Gas turbine jet-propulsion plant. SOC. RATEAU, and ANXIONNAZ, R. Nov. 13, 1956 [Nov. 23, 1955], No. 34709/56. Class 110 (3). [Also in Groups XXXIII and XL (a)] In an aircraft propulsion system operating with hot air or gas, at least two heat sources are provided, one being a combustion apparatus and the other a nuclear reactor, and means are provided to set either or both heat sources into operation as required. In the gas turbine jetpropulsion unit shown in Fig. 1, air from the compressor 1 flows through the nuclear reactor 2, the combustion system 3, the turbine 4 and the propulsion nozzle 5. The combustion system 3 may be used at low altitudes by supplying fuel thereto in the normal manner, whereas at high altitude the reactor 2 may be set in operation by withdrawing the moderator. The reactor 2 and combustion system 3 in Fig. 1 are each mounted concentrically around the turbine-compressor shaft, but in a second arrangement, Fig. 2, the reactor 2 is mounted below the shaft and three combustion chambers 3 are mounted above the shaft in the same transverse plane, air from the compressor being caused to flow either to the reactor or to the combustion chambers by operation of valves 6, 6a. An exhaust reheat device 16 may be provided downstream of the turbine. In a third embodiment, the invention is applied to a gas turbine-propeller unit, the reactor 2 and combustion system again being mounted in series, but both offset below the turbine-compressor shaft. In Fig. 4, air from the compressor is heated indirectly in the heat exchanger 8 by means of an auxiliary fluid such as liquid metal which is heated in the reactor 2. One or more combustion chambers 3 are disposed downstream of the annular heat exchanger 8. With this arrangement, a single reactor may be mounted in the fuselage of the aircraft and connected to a heat exchanger 8 mounted in each propulsion unit. In a gas turbine jetpropulsion engine of the by-pass type, Fig. 7, air from a low-pressure compressor 11 is divided, some passing through a high pressure compressor 1, reactor 2, combustion equipment 3, turbine 4 and propulsion nozzle 5, while the remainder flows through duct 12 and reactor 2a to a propulsion nozzle. The reactor 2a in the duct 12 may be omitted and the reactor 2 constructed as an annular doubleflow unit, the combustion system being disposed around the nuclear reactor. A two-shaft arrangement is employed in this embodiment. The invention is shown applied to a ram-jet unit in Fig. 8, a heat exchanger 8 being disposed in the ram-jet duct which transfers heat from the nuclear reactor 2 to the air stream by means of an auxiliary fluid such as liquid metal. A distributer 14 and nozzles 15 are provided for supply of normal fuel. In a further embodiment an annular ram-jet unit is disposed around a turbo-jet unit such as that shown in Fig. 1, the air stream flowing through the ram-jet duct being heated either in an annular reactor or in an annular combustion section. In all embodiments, the nuclear reactor and combustion system may be used simultaneously.