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GB2240813A - Hypersonic and trans atmospheric propulsion - Google Patents

Hypersonic and trans atmospheric propulsion Download PDF

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Publication number
GB2240813A
GB2240813A GB8620857A GB8620857A GB2240813A GB 2240813 A GB2240813 A GB 2240813A GB 8620857 A GB8620857 A GB 8620857A GB 8620857 A GB8620857 A GB 8620857A GB 2240813 A GB2240813 A GB 2240813A
Authority
GB
United Kingdom
Prior art keywords
turbine
heat exchanger
air
fuel
intake
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB8620857A
Other versions
GB2240813B (en
Inventor
Ralph Murch Denning
Gordon Manns Lewis
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Rolls Royce PLC
Original Assignee
Rolls Royce PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Rolls Royce PLC filed Critical Rolls Royce PLC
Priority to GB8620857A priority Critical patent/GB2240813B/en
Publication of GB2240813A publication Critical patent/GB2240813A/en
Application granted granted Critical
Publication of GB2240813B publication Critical patent/GB2240813B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02CGAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
    • F02C7/00Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
    • F02C7/04Air intakes for gas-turbine plants or jet-propulsion plants
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02CGAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
    • F02C3/00Gas-turbine plants characterised by the use of combustion products as the working fluid
    • F02C3/20Gas-turbine plants characterised by the use of combustion products as the working fluid using a special fuel, oxidant, or dilution fluid to generate the combustion products
    • F02C3/22Gas-turbine plants characterised by the use of combustion products as the working fluid using a special fuel, oxidant, or dilution fluid to generate the combustion products the fuel or oxidant being gaseous at standard temperature and pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02CGAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
    • F02C7/00Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
    • F02C7/22Fuel supply systems
    • F02C7/224Heating fuel before feeding to the burner
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02KJET-PROPULSION PLANTS
    • F02K9/00Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof
    • F02K9/42Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof using liquid or gaseous propellants
    • F02K9/44Feeding propellants
    • F02K9/46Feeding propellants using pumps
    • F02K9/48Feeding propellants using pumps driven by a gas turbine fed by propellant combustion gases or fed by vaporized propellants or other gases
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02KJET-PROPULSION PLANTS
    • F02K9/00Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof
    • F02K9/74Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof combined with another jet-propulsion plant
    • F02K9/78Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof combined with another jet-propulsion plant with an air-breathing jet-propulsion plant

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Abstract

An engine suitable for high speed (up to say Mach 6 cruise) or a trans atmospheric vehicle comprises a turbojet having an air compressor 16, a combustor 30, a first turbine 18 which drives the compressor 16 and a jet pipe 24 which terminates in a variable area nozzle 28. A source of liquid hydrogen is provided and the engine has a first heat exchanger 14 cooled by the fuel for cooling the air entering the intake. A bypass valve 32 is provided so as to bypass the heat exchanger 14 to prevent icing in high humidity air. The hydrogen is vaporised in a second heat exchanger 34 in the jet pipe and the gaseous fuel is used to drive the liquid fuel turbo pump 36 and a second turbine 22 which also drives the air compressor 16. The exhaust from the second turbine 22 is fed to the main combustor 30 to a reheat burner 26 in the jet pipe 24. Liquid oxygen can be used to cool further the intake air or to cool the turbine components. <IMAGE>

Description

IMPROVEMENTS IN HYPERSONIC AND TRANS ATMOSPHERIC PROPULSION This invention relates to the propulsion of hypersonic cruise vehicles and trans atmospheric aerospace vehicles.
The propulsion of vehicles at high velocity in order either to minimise flight transit time, or to effect orbital insertion, currently depends upon either using the atmosphere as the propulsive reaction mass br the use of a vehicle contained reaction mass expelled in the propulsion process (a propellant).
The former types of engine are typically gas turbines or ramjets and the latter rockets.
Gas turbines may be self running from ground level and zero forward speed but are limited in flight by conditions in the compressor, to speeds below Mach 3.5 due to inter alia, very high air inlet temperatures. Ramjets operate satisfactorily only at supersonic speeds from about Mach 2 to Mach 8 or so. Rockets have no speed limitations but have specific fuel consumption (fuel flow/thrust ratio) ten times worse than the former engine types in the overlapping regimes of performance. The desire to construct high speed vehicles has necessitated consideration of placing two or more types of power plant on the same vehicle in order to achieve the performance goal. The use of the pure rocket for orbital insertion has necessitated the use of staged rockets even with the most powerful of the practical chemical propellant combinations (liquid oxygen/liquid hydrogen).In addition to these technical problems, the development cost of ramjets is prohibitively high, due to the necessity of expensive hypersonic wind tunnel test facilities, as the engine will only operate at high speed.
Liquid hydrogen is a very effective fuel yielding 2.8 times the energy of the equivalent mass of kerosine when burned with air. In addition it has a 0 very low storage temperature (-252 C at 1 atmosphere vapour pressure) and a very high specific heat in the gas/vapour phase (14430 J/KgOC) . It is therefore possible to utilise it as a fuel and also as a heat sink for thermodynamic cycles aimed at conditioning the incoming air to an airbreathing engine prior to passing it through the compression and combustion processes.
With air breathing engines capable of flight speeds up to say Mach 6 it is necessary to precool the air entering the intake. It has been proposed in the past to cool the air by passing it through a heat exchanger through which liquid hydrogen is flowed (see for example British patent application 8430157). If this cooling is required in the lower atmosphere to achieve matching necessary to support high mach number operation, then the high humidity of the air may cause icing of the intakes. The practical solution to this problem may be difficult to achieve.
An object of this invention is to provide an engine for a hypersonic cruise or a trans-atmospheric vehicle which is capable of taking off in high humidity air, accelerating to high speeds (of the order of Mach 6) and is capable of sustaining propulsive thrust in rarified atmospheres.
The present invention embodies the essential features of gas turbine compressor technology and hydrogen heat sink concepts in a single engine.
This engine is capable of test bed development and ground running. It performs airbreathing operation to a high speed in the hypersonic regime as a precooled reheated turbojet using hydrogen fuel.
The thermal capacity of the hydrogen precooler system is used to absorb most of the kinetic energy of the intake air at high flight Mach numbers, as enthalpy rise in the fluid, thereby limiting cycle peak temperatures to values within current technology. Unless vehicle considerations dictate an earlier changeover from airbreather to rocket motor, it is the thermal capacity of the working fluids, and materials technology limits, which dictate the Mach number at which this will occur.
Currently with standard technology this would be around Mach 6. The hydrogen flow may be set in accordance with thermodynamics rather than combustion requirements and in fact when used in a trans atmospheric vehicle the engine unit can be separated as a package from the vehicle and returned to earth.
The invention will now be more particularly described, by way of an example, with reference to the accompanying drawings in which: Figure 1 is a diagrammatic representation of one form of engine according to the present invention. The engine 10 comprises a single spool turbojet comprising an air intake 12 having a first heat exchanger 14, an axial flow compressor 16 having a compression ratio of the order of 20:1, a combustor 30, a first turbine 18 which is connected by means of a shaft 20 to the compressor 16 and to a second turbine 22. The engine is provided with a jet pipe 24 which has a re-heat system 26 and a variable area propulsion nozzle 28.
The engine has a liquid hydrogen fuel pump 31 which supplies liquid hydrogen to a selection valve 32.
The selection valve 32 is operable to control the supply of liquid hydrogen to the intake air pre cooler heat exchanger 14, or to bypass the heat exchanger 14. The liquid hydrogen is then passed through a second heat exchanger 34 which is located in the jet pipe 24 downstream of the turbine 18.
Gaseous hydrogen from the heat exchanger 34 flows through a turbine 36 which drives the pump 31. The exhaust of the turbine 36 is fed to the intake of the second turbine 22.
The outlet flow of hydrogen of the turbine 22 is supplied to the burners of the combustor 30, via a control valve 38, and also to the manifolds and burners of the re-heat system 26 via a control valve 40.
The hydrogen driven turbine 36 may also drive a liquid oxidiser pump 42. The outlet of the pump 42 is supplied to a second pre-cooler heat exchanger 44. A control valve 46 is provided to enable the flow from the pump 42 to be supplied to the heat exchanger 44 or to by-pass the heat exchanger 44.
For the initial acceleration of the vehicle, the engine is operated in its air breathing mode and the oxidiser pump 42 is inoperable. During the initial flight where it is likely that the air will have high humidity, the precoolers are rendered inoperable by causing the hydrogen (and oxygen) flow to bypass the heat exchanger. In this way, the formation of snow and ice crystals in the air intake is avoided.
As the vehicle gains speed and altitude and the air becomes less humid and the valve 32 is selectively operated progressively to increase the cooling of the intake air. The air entering the compressor is thus maintained at a low temperature level wallowing satisfactory operation of the engine. The hydrogen which has been heated by the intake and the jet pipe heat exchanger and has been subsequently expanded through the turbine 22 is finally used to fuel both the engine combustor 30 via valve 38 and the reheat system 26 via valve 40. Initially it may be necessary to provide a pre-heated flow of gaseous hydrogen direct to the combustor 30 to start the engine.
The combustion products drive the turbine 18 which combines with turbine 22 to drive compressor 16.
The reheat system is fuelled by the excess hydrogen to fuel/air ratios which may be above the stoichiometric value.
If desired liquid oxygen may be injected into the inlet flow to provide a further source of coolinq and oxidant and into the turbine cooling system to effectively reduce the metal temperature in the turbine system. The cooling of the structures downstream of the turbine may be accomplished using the main hydrogen flow.

Claims (6)

1. A turbojet engine comprising, in flow series, an air intake, an air compressor, a combustor, a turbine connected to drive the air compressor, and a jet pipe which terminates in a propulsion nozzle, there being provided a source of cryogenic liquid fuel, a first heat exchanger located in the intake and operable to receive the liquid fuel and extract heat from the air entering the intake, a bypass means operable for selectively redirecting the liquid fuel so as to bypass the first heat exchanger, a second heat exchanger positioned downstream of the combustor and operable to extract heat from the efflux from the combustor and thereby heat the liquid fuel and vaporise it, and a second turbine connected to drive the air compressor, the second turbine being driven by the gaseous fuel, and the outlet flow of fuel from the second turbine being supplied to the combustor.
2. A turbojet engine according to claim 1 wherein a reheat burner means is provided in the jet pipe and means are provided to use the outlet flow of fuel from the second turbine to supply the reheat burner means.
3. A turbojet according to claim 1 or claim 2 wherein a fuel turbo pump is provided and a turbine of the pump is driven by he gaseous fuel.
4. A turbojet accoridng to any one of claims 1 to 3 wherein a third heat exchanger is provided, said third heat exchanger being provided in the air intake, a source of cryogenic liquid oxidiser is provided and there is means for supplying liquid oxidiser to the third heat exchanger to further cool air entering the intake, and bypass means is provided for selectively redirecting the flow of liquid oxidiser so as to bypass the third heat exchanger.
5. A turbojet according to any one of the preceding claims wherein means are provided for injecting a liquid oxidiser into the air flowing into the intake to further cool the air.
6. A turbojet according to anyone of the preceding claims wherein means are provided for injectina a liquid oxidiser into the first turbine to cool the components of the turbine.
GB8620857A 1986-08-28 1986-08-28 Improvements in hypersonic and trans atmospheric propulsion Expired - Fee Related GB2240813B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB8620857A GB2240813B (en) 1986-08-28 1986-08-28 Improvements in hypersonic and trans atmospheric propulsion

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB8620857A GB2240813B (en) 1986-08-28 1986-08-28 Improvements in hypersonic and trans atmospheric propulsion

Publications (2)

Publication Number Publication Date
GB2240813A true GB2240813A (en) 1991-08-14
GB2240813B GB2240813B (en) 1991-11-27

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Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2664649A1 (en) * 1988-03-23 1992-01-17 Rolls Royce Plc IMPROVEMENTS IN THE ADMISSION OF AIRBORNE PROPELLERS.
FR2681641A1 (en) * 1991-09-25 1993-03-26 Mtu Muenchen Gmbh COOLING DEVICE FOR REACTION ENGINES, ESPECIALLY FOR HYPERSONIC REACTION ENGINES.
GB2295858A (en) * 1994-12-09 1996-06-12 Rolls Royce Plc Liquid hydrogen fuelled powerplant
EP0805303A3 (en) * 1996-05-03 1998-01-28 DaimlerChrysler Aerospace Airbus Gesellschaft mit beschränkter Haftung Method and device for evaporating liquified gas at low temperature
EP0854278A3 (en) * 1993-08-06 1998-12-30 United Technologies Corporation Recovery of heat from the combustion products of a gas turbine engine
CN106014637A (en) * 2016-06-07 2016-10-12 中国人民解放军国防科学技术大学 Air precooling compression aircraft engine and hypersonic velocity aircraft
EP3623604A1 (en) * 2018-09-14 2020-03-18 United Technologies Corporation Hybrid expander cycle with pre-compression cooling and turbo-generator
US11077949B2 (en) * 2018-10-05 2021-08-03 The Boeing Company Dual turbine thermal management system (TMS)
EP3978736A1 (en) * 2020-09-30 2022-04-06 Rolls-Royce plc Fuel delivery
CN114352436A (en) * 2021-12-15 2022-04-15 西安航天动力研究所 Metal powder fuel air-water cross-medium engine and control method thereof
US11383852B2 (en) * 2019-05-20 2022-07-12 Rolls-Royce Plc Turbo engine with cooler for cooling inlet air and turbine for expanding cryogenic fuel
FR3120393A1 (en) * 2021-03-08 2022-09-09 Safran Fuel conditioning system and method configured to supply an aircraft turbine engine with fuel from a cryogenic tank
EP4187070A1 (en) * 2021-11-29 2023-05-31 Airbus Operations, S.L.U. Gas turbine
WO2024083502A1 (en) * 2022-10-21 2024-04-25 Safran Fuel conditioning system and method for powering a turbomachine
WO2024088516A1 (en) * 2022-10-25 2024-05-02 Destinus Sa Air turborocket apparatus with boiler
EP4438868A1 (en) * 2023-03-28 2024-10-02 Rolls-Royce plc Gas turbine engine
US12252266B2 (en) 2022-10-24 2025-03-18 Rolls-Royce Plc Aircraft engine fuel system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108910059B (en) * 2018-07-18 2020-07-31 中国人民解放军国防科技大学 A pre-cooled air inlet and hypersonic aircraft

Cited By (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2664649A1 (en) * 1988-03-23 1992-01-17 Rolls Royce Plc IMPROVEMENTS IN THE ADMISSION OF AIRBORNE PROPELLERS.
FR2681641A1 (en) * 1991-09-25 1993-03-26 Mtu Muenchen Gmbh COOLING DEVICE FOR REACTION ENGINES, ESPECIALLY FOR HYPERSONIC REACTION ENGINES.
GB2260578A (en) * 1991-09-25 1993-04-21 Mtu Muenchen Gmbh Heat transfer between fuel and air in supersonic jet engine
GB2260578B (en) * 1991-09-25 1995-01-18 Mtu Muenchen Gmbh Cooling device for jet engines
EP0854278A3 (en) * 1993-08-06 1998-12-30 United Technologies Corporation Recovery of heat from the combustion products of a gas turbine engine
GB2295858A (en) * 1994-12-09 1996-06-12 Rolls Royce Plc Liquid hydrogen fuelled powerplant
EP0805303A3 (en) * 1996-05-03 1998-01-28 DaimlerChrysler Aerospace Airbus Gesellschaft mit beschränkter Haftung Method and device for evaporating liquified gas at low temperature
CN106014637A (en) * 2016-06-07 2016-10-12 中国人民解放军国防科学技术大学 Air precooling compression aircraft engine and hypersonic velocity aircraft
CN106014637B (en) * 2016-06-07 2017-12-19 中国人民解放军国防科学技术大学 Air precooling compresses aero-engine and Hypersonic Aircraft
US10989117B2 (en) 2018-09-14 2021-04-27 Raytheon Technologies Corporation Hybrid expander cycle with pre-compression cooling and turbo-generator
EP3623604A1 (en) * 2018-09-14 2020-03-18 United Technologies Corporation Hybrid expander cycle with pre-compression cooling and turbo-generator
US11077949B2 (en) * 2018-10-05 2021-08-03 The Boeing Company Dual turbine thermal management system (TMS)
EP4495411A3 (en) * 2019-05-20 2025-03-26 Rolls-Royce plc Turbojet engine for hypersonic vehicle
US11383852B2 (en) * 2019-05-20 2022-07-12 Rolls-Royce Plc Turbo engine with cooler for cooling inlet air and turbine for expanding cryogenic fuel
EP3741972B1 (en) * 2019-05-20 2025-01-08 Rolls-Royce plc Turbojet engine for hypersonic vehicle
US20220297847A1 (en) * 2019-05-20 2022-09-22 Rolls-Royce Plc Engine
US11685541B2 (en) * 2019-05-20 2023-06-27 Rolls-Royce Plc Turbo engine with cooler for cooling inlet air and turbine for expanding cryogenic fuel
US11828232B2 (en) 2020-09-30 2023-11-28 Rolls-Royce Plc Fuel injection
EP3978736A1 (en) * 2020-09-30 2022-04-06 Rolls-Royce plc Fuel delivery
EP3978737A1 (en) * 2020-09-30 2022-04-06 Rolls-Royce plc Complex cycle gas turbine engine
US12006871B2 (en) 2020-09-30 2024-06-11 Rolls-Royce Plc Fuel delivery system for delivering hydrogen fuel to a fuel injection system in a complex cycle gas turbine engine
US11970975B2 (en) 2020-09-30 2024-04-30 Rolls-Royce Plc Fuel delivery system for delivering hydrogen fuel to a fuel injection system in a gas turbine engine
FR3120393A1 (en) * 2021-03-08 2022-09-09 Safran Fuel conditioning system and method configured to supply an aircraft turbine engine with fuel from a cryogenic tank
WO2022189154A1 (en) * 2021-03-08 2022-09-15 Safran Fuel conditioning system and method configured to supply an aircraft turbine engine using fuel from a cryogenic tank
US12371183B2 (en) 2021-03-08 2025-07-29 Safran Fuel conditioning system and method configured to power an aircraft turbine engine using fuel from a cryogenic tank
EP4187070A1 (en) * 2021-11-29 2023-05-31 Airbus Operations, S.L.U. Gas turbine
CN114352436B (en) * 2021-12-15 2023-01-20 西安航天动力研究所 Metal powder fuel air-water cross-medium engine and control method thereof
CN114352436A (en) * 2021-12-15 2022-04-15 西安航天动力研究所 Metal powder fuel air-water cross-medium engine and control method thereof
WO2024083502A1 (en) * 2022-10-21 2024-04-25 Safran Fuel conditioning system and method for powering a turbomachine
FR3141212A1 (en) * 2022-10-21 2024-04-26 Safran Fuel conditioning system for supplying an aircraft turbomachine, method of supplying a turbomachine
US12252266B2 (en) 2022-10-24 2025-03-18 Rolls-Royce Plc Aircraft engine fuel system
WO2024088516A1 (en) * 2022-10-25 2024-05-02 Destinus Sa Air turborocket apparatus with boiler
EP4438868A1 (en) * 2023-03-28 2024-10-02 Rolls-Royce plc Gas turbine engine
US12209536B2 (en) 2023-03-28 2025-01-28 Rolls-Royce Plc Gas turbine engine

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PCNP Patent ceased through non-payment of renewal fee

Effective date: 19920828