Turbofan jet engine with low pressure shaft passing outside of core engine

• US 9,828,911 B2
• Filed: 07/09/2014
• Issued: 11/28/2017
• Est. Priority Date: 07/10/2013
• Status: Active Grant

• Current Assignee: Rolls-Royce Deutschland Limited & Company KG (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce Deutschland Limited & Company KG (Rolls-Royce Holdings Plc)
• Inventors: Burghardt, Sascha
• Primary Examiner(s): Rivera, Carlos A
• Application Number:
  US14/327,013
• Publication Number:
  US 20150013307A1
• Time in Patent Office: 1,238 Days
• CPC Class Codes: F01D 13/003 with at least two independent shafts, i.e. cross-compound
• CPC Class Codes: F01D 13/02 Working-fluid interconnection of machines or engines
• CPC Class Codes: F02C 3/045 having compressor and turbine passages in a single rotor-module F02C3/073 takes precedence
• CPC Class Codes: F02C 3/10 with another turbine driving an output shaft but not driving the compressor
• CPC Class Codes: F02C 6/02 Plural gas-turbine plants having a common power output
• CPC Class Codes: F05D 2250/312 the axes being parallel to each other

Abstract

A turbofan engine includes a core engine, having a high-pressure compressor, a combustion chamber and a high-pressure turbine which are coupled to one another via a high-pressure shaft, at least one fan from which gas is supplied into both a primary flow duct and a secondary flow duct of the turbofan engine, at least one low-pressure turbine arranged behind the core engine, and at least one low-pressure shaft, with each low-pressure shaft coupling a fan to a low-pressure turbine. It has been provided that no low-pressure shaft of the turbofan engine passes through the core engine.

Claims

1. An aircraft turbofan engine comprising:

only one core engine, including a high-pressure compressor, a combustion chamber and a high-pressure turbine which are coupled to one another via a high-pressure shaft,

a primary flow duct for flowing air into the core engine,

a secondary flow duct for flowing air outside the core engine,

at least one fan for supplying air into both the primary flow duct and the secondary flow duct, wherein the secondary flow duct and the core engine have a same flow direction, the at least one fan driving a major proportion of an air mass ingested by the aircraft turbofan engine into the secondary flow duct past the core engine for propulsion of the aircraft turbofan engine,

at least one low-pressure turbine arranged behind the core engine, and

at least one low-pressure shaft coupling the at least one fan to the at least one low-pressure turbine,

wherein none of the at least one low-pressure shaft of the turbofan engine passes through the core engine;

wherein each one of the at least one low-pressure shaft runs substantially parallel to the high-pressure shaft, such that a deviation from parallel between each one of the at least one low-pressure shaft and the high-pressure shaft is no greater than 5°

;

wherein the at least one fan comprises at least two fans;

wherein the at least one low-pressure turbine comprises at least two low-pressure turbines; and

wherein the at least one low-pressure shaft comprises at least two low-pressure shafts, with each of the least two fans being respectively coupled to one of the at least two low-pressure turbines by one of the at least two low-pressure shafts.

2. The aircraft turbofan engine in accordance with claim 1, wherein none of the at least two low-pressure shafts of the turbofan engine runs coaxially to the high-pressure shaft of the turbofan engine.

3. The aircraft turbofan engine in accordance with claim 1, wherein the primary flow duct or part-ducts of the primary flow duct are deflected in front of and behind the core engine in a radial direction such that a section of the primary flow duct passing through the core engine is radially spaced from each secondary flow duct.

4. The aircraft turbofan engine in accordance with claim 3, wherein relative to a flow direction an axially front end of the primary flow duct is provided behind each of the at least two fans.

5. The aircraft turbofan engine in accordance with claim 3, wherein relative to a flow direction an axially rear end of the primary flow duct is provided in front of each of the at least two low-pressure turbines.

6. The aircraft turbofan engine in accordance with claim 4, wherein behind each of the at least two fans and in front of each of the at least two low-pressure turbines the primary flow duct or part-ducts of the primary flow duct run in a curve, passing through a turning point of the curve.

7. The aircraft turbofan engine in accordance with claim 1, wherein the primary flow duct forms at an axially front end thereof at least two ducts which merge in front of the core engine, where each duct is associated with one of the at least two fans, so that part of the airflow passing a respective one of the at least two fans is guided into each of the at least two ducts.

8. The aircraft turbofan engine in accordance with claim 1, wherein the primary flow duct splits behind the core engine into at least two ducts which each lead to one of the at least two low-pressure turbines.

9. The aircraft turbofan engine in accordance with claim 1, wherein the core engine is arranged offset to a plane defined by the at least two low-pressure shafts.

10. The aircraft turbofan engine in accordance with claim 1, wherein the engine includes at least one outer casing that defines a plurality of secondary flow ducts matching a quantity of the at least two fans.

11. The aircraft turbofan engine in accordance with claim 1, wherein the at least one secondary flow duct ends in an axial direction in front of the primary flow duct.

12. The aircraft turbofan engine in accordance with claim 1, wherein the core engine further includes a medium-pressure compressor and a medium-pressure turbine coupled to one another by a medium-pressure shaft.