Patent GB-651365-A (GB)
Title: Improvements in power gas plants, in particular for use on flying machines
IPC: F02B39/08
Filed: 1948-09-15
Abstract: 651,365. Gas turbine plant; jet propulsion plant. SOC. INDUSTRIELLE GENERALE DE MECANIQUE APPLIQUEE (S.I.G.M.A.). Sept. 15, 1948, Nos. 24250 and 24251. Convention dates Sept. 23, 1947 and April 21, 1948. [Class 110(iii)] A useful power turbine 7; Fig. 1, or a propulsion jet, is driven by the combined exhausts of a gas turbine 3 and an int e r n a 1 combustion engine 1. The engine 1 drives a high pressure piston compressor 2 which supplies air to the combustion chamber 6 of the gas turbine 3. The turbine 3 drives a low pressure air compressor 4 which delivers air to the compressor 2 and supercharges the engine 1. The plant is controlled by the simultaneous and related regulation of fuel pumps 60, 61 which deliver fuel to the combustion chamber and the internal combustion engine. A hand or governor controlled rod 47 is pivotally connected to links 48, 49 having rollers 50, 51 which run on cam surfaces 53, 54. The links are connected to control rods 58, 59 of the pumps 60, 61. The cam part 55 can be moved axially or tilted to vary the relation between the movements of the rods 58, 59. For starting, a valve 41 directs all the air from compressor 4 into the combustion chamber 6 and the turbine exhaust is open to atmosphere at a valve 43. When the turbine is running the valve 41 is moved to direct part of the air to the internal combustion engine which exhausts to atmosphere at a valve 46. Starting motors 44, 45 are provided. Finally, the valve 41 is moved to cut off the air supply through pipe 40 and the valves 43, 46 are moved to direct the exhausts to the turbine 7. In the plant shown in Fig. 5, the compressor 20, turbine 24, internal combustion engine and piston compressor unit 23 and useful power turbine 28 correspond to the compressor 4, turbine 3, internal combustion engine and compressor 1, 2 and useful power turbine 7 of Fig. 1. To this plant is added a turbine 15 which exhausts to a propulsion jet nozzle. The turbine 15 drives a compressor 10 having an initial dual-flow stage followed by a single-flow stage 14. The parts of the enlarged plant are arranged for both series and parallel working. In series working, for high altitudes, the valves 19, 31, 33 and 36 are positioned as shown. The exhaust of the turbine 28 is reheated at 35 and passes to the turbine 15. Part of the air compressed in the dual-flow stage is led to a thrust augmenter duct 13 and may be heated as by a burner 38. The air delivered by the stage 14 goes to the inlet of the two-stage centrifugal compressor 20. In parallel working, for lower altitudes, the valves 19, 33 and 36 are opened and the valve 31 is shut. Air from the stage 14 now goes to a combustion chamber 18 which supplies the turbine 15 with working fluid. Air from the dual-flow stage goes to the augmenter duct 13 and by a duct 32 to the compressor 20. The exhaust of the turbine 28 goes to the augmenter duct 13. Turbines 28 and 15 are on separate shafts and may be connected by an overriding clutch which permits the turbine 28 to go faster than the turbine 15. Coolers 21, 22 are provided with cooling air which has been cooled in an exchanger 37 in the augmenter duct.