Compressor system

• US 9,890,704 B2
• Filed: 04/01/2014
• Issued: 02/13/2018
• Est. Priority Date: 05/01/2013
• Status: Active Grant

• Current Assignee: Derwent Aviation Consulting Ltd.
• Original Assignee: Derwent Aviation Consulting Ltd.
• Inventors: Speak, Trevor H., Sellick, Robert J.
• Primary Examiner(s): Nguyen, Ninh H
• Application Number:
  US14/785,628
• Publication Number:
  US 20160069260A1
• Time in Patent Office: 1,414 Days
• CPC Class Codes: F01D 15/12 Combinations with mechanical gearing driven by multiple engines F01D13/00
• CPC Class Codes: F02C 3/067 having counter-rotating rotors F02C3/073 takes precedence
• CPC Class Codes: F02C 3/107 with two or more rotors connected by power transmission
• CPC Class Codes: F02C 3/34 with recycling of part of the working fluid, i.e. semi-closed cycles with combustion products in the closed part of the cycle
• CPC Class Codes: F02C 7/36 Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user F02C3/107 - F02C3/13 and F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H
• CPC Class Codes: F02K 3/06 with front fan
• CPC Class Codes: F05D 2220/36 specially adapted for the fan of turbofan engines
• CPC Class Codes: F05D 2220/62 with energy recovery turbines
• CPC Class Codes: F05D 2260/40311 of the epicyclical, planetary or differential type
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

In a gas turbine engine, the booster compressor is driven by both the low pressure or fan shaft and high pressure shaft through a differential gear arrangement. The rotational speed of the booster compressor is intermediate between the speed of the fan and the speed of the high pressure compressor.

Claims

1. A compressor system for a turbo machine, the turbo machine including (1) a low pressure shaft coupled to a low pressure turbine;

and (2) a high pressure shaft coupled to a high pressure turbine, the compressor system comprising;

a fan driven by the low pressure turbine via the low pressure shaft;

a booster compressor; and

an epicyclic gear unit;

wherein;

the low pressure shaft is coupled to a first input member of the epicyclic gear unit,

the high pressure shaft is coupled to a second input member of the epicyclic gear unit,

the booster compressor is coupled to an output member of the epicyclic gear unit,

the booster compressor is driven by the low pressure shaft and the high pressure shaft, and

a proportion of a torque extracted from each of the low pressure shaft and the high pressure shaft remains constant throughout a running range of the turbo machine.

2. The compressor system as claimed in claim 1, wherein:

the output member of the epicyclic gear unit is provided as a planet carrier, the planet carrier holding an array of planet gears,

the first input member of the epicyclic gear unit is an annular gear positioned radially outward of, and rotatably engaged with, the array of planet gears,

the array of planet gears is positioned radially outward of, and rotatably engaged with, the second input member of the epicyclic gear unit, and

the second input member of the epicyclic gear unit is provided as a sun gear.

3. The compressor system as claimed in claim 2, wherein diameters of gears of the epicylic gear unit are provided such that, in use, the booster compressor rotates in a same direction as the fan and, over a predetermined range of rotational speeds of the low pressure shaft and the high pressure shaft, the booster compressor rotates faster than the fan.

4. The compressor system as claimed claim 1, wherein:

the output member of the epicyclic gear unit is an annular gear positioned radially outward of, and rotatably engaged with, an array of planet gears,

the first input member of the epicyclic gear unit is provided as a planet carrier, the planet carrier holding the array of planet gears,

the array of planet gears is positioned radially outward of, and rotatably engaged with, the second input member of the epicyclic gear unit, and

the second input member of the epicyclic gear unit is provided as a sun gear.

5. The compressor system as claimed in claim 4, wherein the low pressure shaft and high pressure shaft are configured, in use, to contra-rotate.

6. The compressor system as claimed in claim 4, wherein diameters of gears of the epicylic gear unit are provided such that, in use, the booster compressor rotates in a same direction as the fan and, over a predetermined range of rotational speeds of the low pressure shaft and the high pressure shaft, the booster compressor rotates faster than the fan.

7. The compressor system as claimed in claim 1, wherein:

the turbo machine comprises an engine core flow path,

the booster compressor is provided one of at or downstream of an intake of the engine core flow path, and

the fan is provided upstream of the booster compressor in the engine core flow path.

8. The compressor system as claimed claim 7, wherein the turbo machine further comprises a bypass duct positioned radially outward of the engine core flow path.

10. The gas turbine engine as claimed in claim 8, wherein:

the output member of the epicyclic gear unit is provided as a planet carrier, the planet carrier holding an array of planet gears,

the first input member of the epicyclic gear unit is an annular gear positioned radially outward of, and rotatably engaged with, the array of planet gears,

the array of planet gears is positioned radially outward of, and rotatably engaged with, the second input member of the epicyclic gear unit, and

the second input member of the epicyclic gear unit is provided as a sun gear.

11. The gas turbine engine as claimed in claim 10, wherein diameters of gears of the epicylic gear unit are provided such that, in use, the booster compressor rotates in a same direction as the fan and, over a predetermined range of rotational speeds of the low pressure shaft and the high pressure shaft, the booster compressor rotates faster than the fan.

9. A gas turbine engine, comprising:

a turbo machine comprising;

a low pressure shaft coupled to a low pressure turbine; and

a high pressure shaft coupled to a high pressure turbine; and

a compressor system comprising;

a fan driven by the low pressure turbine via the low pressure shaft;

a booster compressor; and

an epicyclic gear unit;

wherein;

the low pressure shaft is coupled to a first input member of the epicyclic gear unit,

the high pressure shaft is coupled to a second input member of the epicyclic gear unit,

the booster compressor is coupled to an output member of the epicyclic gear unit,

the booster compressor is driven by the low pressure shaft and the high pressure shaft, and

a proportion of a torque extracted from each of the low pressure shaft and the high pressure shaft remains constant throughout a running range of the gas turbine engine.

12. The gas turbine engine as claimed in claim 9, wherein:

the output member of the epicyclic gear unit is an annular gear positioned radially outward of, and rotatably engaged with, an array of planet gears,

the first input member of the epicyclic gear unit is provided as a planet carrier, the planet carrier holding the array of planet gears;

the array of planet gears is positioned radially outward of, and rotatably engaged with, the second input member of the epicyclic gear unit; and

the second input member of the epicyclic gear unit is provided as a sun gear.

13. The gas turbine engine as claimed in claim 12, wherein the low pressure shaft and high pressure shaft are configured, in use, to contra-rotate.

14. The gas turbine engine as claimed in claim 12, wherein diameters of gears of the epicylic gear unit are provided such that, in use, the booster compressor rotates in a same direction as the fan and, over a predetermined range of rotational speeds of the low pressure shaft and the high pressure shaft, the booster compressor rotates faster than the fan.

15. The gas turbine engine as claimed in claim 9, further comprising an engine core flow path,

wherein:

the booster compressor is provided one of at or downstream of an intake of the engine core flow path, and

the fan is provided upstream of the booster compressor in the engine core flow path.

16. The gas turbine engine as claimed in claim 15, further comprising a bypass duct positioned radially outward of the engine core flow path.