Patent GB-1175376-A (GB)
Title: Gas Turbine Power Plants.
Inventor: EMERICK GEORGE
IPC: F02K3/04
Filed: 1966-11-30
Abstract: 1,175,376. Propelling helicopters. ROLLSROYCE Ltd. 29 Nov., 1967 [30 Nov., 1966], No.53715/66. Heading B7G. [Also in Division F1] In Fig. 1, the invention is shown applied to a gas turbine power plant for aircraft in which one power turbine drives a helicopter lift rotor 14 and the other power turbine drives a ducted fan providing forward thrust. The power plant comprises compressor 1, combustion equipment 3, combustion gases from which are directed by means of fixed inlet nozzle guide vanes 4 to a turbine 5 connected to drive the compressor 1. Gases discharging from the turbine 5 are directed by a set of adjustable inlet nozzle guide vanes 6 to a first power turbine 8 which is connected through shaft 11, gearing 12 and shaft 13 to drive the lift rotor 14. Gases discharging from the turbine 8 are directed by a set of adjustable inlet nozzle guide vanes 9 to a second power turbine 10 which is connected by means of a ring member 15 to a set of ducted fan blades 16 disposed in a duct 17. The duct 17 has an inlet 18 at its upstream end and a propulsion nozzle 19 at its outlet, a set of adjustable guide vanes 24 being disposed upstream of the fan blades 16. The gases from the turbine 10 discharge through a propulsion nozzle 20. The rings of turbine inlet nozzle guide vanes 6 and 9 are interconnected as indicated at 7 and the guide vanes are also interconnected with the fan inlet guide vanes 24 by linkage indicated at 26. The shaft 13 of the lift rotor extends across the exhaust gas duct and the fan duct, being enclosed within a tubular housing 21 and fairings 22, 23. In Fig. 2 the first power turbine is shown at 28 and the second power turbine at 29, the turbines having interconnected sets of adjustable inlet nozzle guide vanes 37, 38 respectively. The first power turbine is connected to drive a lift rotor by means of gearing 33 and shaft 34, the drive being taken from the forward end of the turbine shaft. The second power turbine 29 drives a set of ducted fan blades 31 as in the first embodiment, a set of adjustable inlet guide vanes 39 being disposed upstream of the fan blades. In Fig. 5 the first power turbine 28 drives the lift rotor 27 as in the previous embodiment, but the gases from the turbine 28 discharge through radially-outwardly extending ducts 43 and are directed by a set of adjustable inlet nozzle guide vanes 48 on to the second power turbine 49, the turbine 49 being mounted at the tips of ducted fan blades 50. The fan blades 50 are disposed in a duct 44 and a set of adjustable inlet guide vanes 54 is disposed upstream of the fan blades. The turbine inlet nozzle guide vanes 52, 48 and the fan inlet guide vanes 54 are interconnected as indicated at 53, 55. In Fig. 6, not shown, the first power turbine 28 drives the lift rotor as in Figs. 2 and 5, but the second power turbine rotor 29 drives the ducted fan 57 through shaft 56. The exhaust gases from the turbine 29 discharge radially outwardly and then axially through ducting 62 and nozzle 63. The fan duct 60, 58 crosses the exhaust gas duct 62 so that the fan air nozzle 59 is disposed radially within the exhaust gas nozzle 63. In Fig. 7, the first power turbine 68 is connected by ring member 69 to ducted fan blades 70, the fan duct having an inlet 72 and outlet 76, a set of adjustable inlet guide vanes 73 being disposed upstream of the fan blades 70. The gases from the turbine 68 discharge through duct 74 which crosses the fan duct and pass to a second power turbine 79 which is a tip turbine driving a lift fan 80. The inlet nozzle guide vanes 66 and 78 of the first and second power turbines 68 and 79 respectively are interconnected and are also connected with the inlet guide vanes 73 of the ducted fan 70. In a further embodiment, Fig. 8, not shown, a tip turbine 79 driving a lift fan 80 is again utilized but the first power turbine 68 drives the ducted fan 83 through shaft 82, the gas flow duct from the first power turbine 68 crossing the fan duct upstream of the inlet guide vane assembly 85.