Combined turbojet and ramjet engine

Patent metadata

Field	Value
Publication number	US-9422889-B2
Application number	US-201113989070-A
Country	US
Kind code	B2
Filing date	Nov 14, 2011
Priority date	Nov 23, 2010
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

A combined engine includes a turbopump including a pump injecting hydrogen into a heater arranged in an outer casing downstream from a central body, and a subsonic turbine driving the pump, which turbine receives partially-expanded hydrogen collected at an outlet from the heater to apply the hydrogen to a supersonic turbine to operate the engine as a turbojet. The hydrogen from the supersonic turbine is collected in tubes inside the central body to be sent to a combustion chamber defined downstream from the central body, while the hydrogen that is partially expanded in the subsonic turbine is sent directly to the combustion chamber via injectors to operate the engine as a ramjet.

First claim

The invention claimed is:

1. A combined turbojet and ramjet engine configured to avoid using liquid oxygen, comprising:
an outer casing having an upstream air inlet and a downstream exhaust nozzle where a downstream direction is defined by an air flow from the upstream air inlet to the downstream exhaust nozzle;
a central body connected to the outer casing by structural arms and co-operating with the outer casing to form an air inlet sleeve and an air flow passage;
at least one first air compressor stage comprising a first supersonic turbine arranged in the central body and a first rotor comprising blades arranged in the air flow passage, the first rotor being driven by the first supersonic turbine to operate the engine in a turbojet mode and the blades of the first rotor being feathered to operate the engine in a ramjet mode, the first supersonic turbine rotating around a longitudinal axis of the central body;
an annular hydrogen injection tube connected to an inlet of the first supersonic turbine, the annular hydrogen injection tube located inside the central body and downstream of the first supersonic turbine;
a first collection tubes connected to an outlet of the first supersonic turbine, the first collection tubes located upstream of the first supersonic turbine;
a turbopump comprising a pump that is fed with liquid hydrogen from a hydrogen tank to inject the liquid hydrogen into a heater arranged in the outer casing downstream from the central body and a subsonic turbine driving the pump, the subsonic turbine receiving a partially-expanded hydrogen collected at an outlet from the heater; and
a 3-port T-valve arranged at an outlet of the subsonic turbine to, in a first position, supply a hydrogen that is further expanded in the subsonic turbine to the annular hydrogen injection tube and then to the first supersonic turbine to operate the engine in the turbojet mode, the hydrogen from the outlet of the first supersonic turbine then being collected in the first collection tubes inside the central body to be sent to a combustion chamber defined inside the outer casing downstream from the central body, in a second position, the 3-port T-valve switches the hydrogen that is further partially expanded in the subsonic turbine directly into the combustion chamber by injectors to operate the engine in the ramjet mode.

2. A combined engine according to claim 1 , further comprising
a second air compressor stage comprising a second supersonic turbine arranged in the central body and a second rotor comprising contrarotating blades arranged in the air flow passage and configured to be selectively driven by the second supersonic turbine to operate the engine in the turbojet mode, said contrarotating blades being feathered to operate the engine in the ramjet mode, the second supersonic turbine also receiving the hydrogen that has been further expanded in the subsonic turbine from the annular hydrogen injection tube which is located upstream of the second supersonic turbine, the hydrogen from an outlet of the second supersonic turbine then being collected in second tubes located inside the central body and downstream of the second supersonic turbine to be sent to the combustion chamber to operate the engine in the turbojet mode.

3. A combined engine according to claim 1 , further comprising a post-combustion device comprising flame-holder rings arranged in the combustion chamber between a rear portion of the central body and a portion of the outer casing containing the heater.

4. A combined engine according to claim 1 , wherein the heater comprises a heat exchanger comprising regenerating walls and regenerating fins.

5. A combined engine according to claim 4 , wherein the heater comprises a heat exchanger comprising walls with milled channels made of a material based on copper or on high-temperature nickel.

Assignees

• Conrardy Jean-Marie
• Soulier Nicolas
• Snecma

Inventors

• Conrardy Jean-Marie
• Soulier Nicolas

Classifications

• F02C7/224

  Heating fuel before feeding to the burner · CPC title

• F02K3/072

  with counter-rotating {, e.g. fan} rotors · CPC title

• Y02T50/672

  Cross-Sectional Technologies · mapped topic

• F02K3/00

  Plants including a gas turbine driving a compressor or a ducted fan · CPC title

• F02K7/16 Primary

  Composite ram-jet/turbo-jet engines · CPC title