Rotational machine, such as a turbomachine, and engines and flying machines incorporating same
A rotational machine such as a turbocompressor has a fluid recovery system for recovering leaked working fluid such as gaseous helium in a helium circuit which has leaked past a shaft seal, a purifier being provided for removing contaminants from the working fluid, and turbocompressor may have one fluid such as helium or hydrogen working through one turbo component such as a turbine thereof and a second working fluid such as air or helium working through a second turbo component such as a compressor thereof, the rotational machine being installable in an engine of a flying machine.
1. A rotational machine having a working component for communicating a working fluid from an inlet to an outlet thereof, comprising:
a turbine having a turbine rotor and a compressor having a compressor rotor, the turbine rotor and the compressor rotor being connected by a connector; and
a working fluid recovery system for the recovery of a first working fluid in the region of the connector;
in which:
the connector is adapted to form at least part of a drive connection between the turbine and the compressor;
the connector comprises a rotatable shaft and in which a first shaft seal is provided for substantially sealing the first working fluid against transmission thereof along the shaft;
the compressor is adapted to compress a second working fluid; and
the working fluid recovery system comprises at least one recovery compressor and a recovery turbine, in which the recovery turbine has an inlet path adapted to draw the first working fluid from an inlet region of the turbine of the working component and/or an outlet path adapted to supply the first working fluid to an outlet region of the turbine of the working component, and in which a recovery turbine rotor is connected to a drive shaft driving a recovery compressor rotor of the recovery compressor.
2. A rotational machine as claimed in claim 1 , which comprises a turbomachine which is adapted to operate with the first working fluid in a closed circuit.
3. A rotational machine as claimed in claim 1 , which is adapted to operate with helium as the first working fluid.
4. A rotational machine as claimed in claim 1 , in which the second working fluid is air.
5. A rotational machine as claimed in claim 1 , in which the first shaft seal is located fluidly between one of said turbine and compressor rotors and an inlet to the working fluid recovery system.
6. A rotational machine as claimed in claim 1 , which is adapted to operate with a first pressure on a rotor side of the first shaft seal higher than a second pressure on a lower pressure side of the first shaft seal.
7. A rotational machine as claimed in claim 6 , in which the first shaft seal, on a side thereof facing said one of said turbine and compressor rotors, is adapted to be subjected to a seal pressure substantially equal to pressure at a working fluid region of the working component.
8. A rotational machine as claimed in claim 7 , which further comprises:
a second shaft seal and a third shaft seal, the working fluid recovery system being adapted to draw leaked fluid from between the first shaft seal and one of the second or third shaft seals, the pressure in a chamber between the other one of the second or third shaft seals and the first shaft seal being maintainable at lower than the pressure between the first shaft seal and the other one of the second or third shaft seals; and
a conduit to draw off leakage into the chamber between the first shaft seal and the other one of the second or third shaft seals.
9. A rotational machine as claimed in claim 6 , in which the recovery compressor has an inlet path adapted to draw fluid from a recovery space bounded at least partly by the lower pressure side of the first shaft seal and/or an outlet path adapted to supply the first working fluid to an outlet region of the working component.
10. A rotational machine as claimed in claim 9 , comprising a second shaft seal and in which the recovery space is between the first shaft seal and the second shaft seal.
11. A rotational machine as claimed in claim 1 , in which the drive shaft is adapted to transmit torque from the recovery turbine rotor to the recovery compressor rotor.
12. A rotational machine as claimed in claim 1 , in which the working fluid recovery device comprises a purifier for removing contaminants from the first working fluid.
13. A rotational machine as claimed in claim 12 , in which the purifier is adapted to remove at least oxygen from the first working fluid.
14. A rotational machine as claimed in claim 12 , in which the purifier is adapted to remove at least hydrogen from the first working fluid.
15. A rotational machine as claimed in claim 12 , in which the purifier comprises a palladium component adapted to remove hydrogen from helium.
16. A rotational machine as claimed in claim 1 , in which:
the turbine rotor is a helium fluid rotor, and the compressor rotor is a non-helium fluid rotor;
the rotatable shaft drivingly connects the helium fluid rotor to the non-helium fluid rotor; and
the rotational machine is adapted to operate with a pressure gradient along the shaft drivingly connecting the helium and non-helium fluid rotors, with a higher pressure on a helium fluid side of the first shaft seal than on a non-helium fluid side of the first shaft seal.
17. An engine comprising a rotational machine as claimed in claim 16 .
18. An engine as claimed in claim 17 , wherein the turbine is a helium turbine, and further comprising a circuit passing through the helium turbine, the circuit adapted for the circulation of gaseous helium.
19. An engine as claimed in claim 18 , wherein the engine is adapted to compress air for use in combustion, the engine comprising an air path therethrough which passes through the compressor which comprises an air compressor of the rotational machine, the air compressor being driven by the helium turbine.
20. An engine as claimed in claim 17 , which is adapted for engine ignition into an air-breathing mode in which it is adapted to produce motive thrust in continuous operation at zero air speed.
21. A flying machine, comprising an engine adapted to provide motive thrust thereto, the engine being as claimed in claim 17 .
22. A flying machine as claimed in claim 21 , further comprising a fuselage with aerodynamic control surfaces adapted to operate together with the engine, wherein the engine is adapted for engine ignition into an air-breathing mode in which it is adapted to produce motive thrust in continuous operation at zero air speed for a controlled horizontal take-off from zero airspeed with the engine in the air-breathing mode.