Geared gas turbine engine
AssigneeROLLS-ROYCE plc
InventorMark SPRUCE
Life of this patent
Estimating the term…
Abstract
Gas turbine engine includes: an engine core including a turbine, compressor, and core shaft connecting the turbine to the compressor; a fan located upstream of the core; and a gearbox that is configured to receive an input from the core shaft, and output drive to a fan shaft via an output of the gearbox so as to drive the fan at a lower rotational speed than the core shaft. A fan shaft radial bending stiffness to moment of inertia ratio defined as: a radial bending stiffness of the fan shaft at the output of the gearbox the moment of inertia of the fan is in a range from 2.5×10−2 Nkg−1m−1mm−2 to 6.0 Nkg−1m−1 mm−2.
Claims20
A gas turbine engine for an aircraft comprising:
- an engine core comprising a turbine, a compressor, and a core shaft connecting the turbine to the compressor;
- a fan located upstream of the engine core, the fan comprising a plurality of fan blades;
- and
- a gearbox that is configured to receive an input from the core shaft, and output drive to a fan shaft via an output of the gearbox so as to drive the fan at a lower rotational speed than the core shaft, wherein:
- a fan shaft radial bending stiffness to moment of inertia ratio defined as:
- the
-
- radial
-
- bending
-
- stiffness
-
- of
-
- the
-
- fan
-
- shaft
-
- at
-
- the
-
- output
-
- of
-
- the
-
- gearbox
- the
-
- moment
-
- of
-
- inertia
-
- of
-
- the
-
- fan
- is in a range from 2.5×10−2 Nkg−1m−1mm−2 to 6.0 Nkg−1m−1mm−2;
- and
- the fan shaft is mounted within the engine by a fan shaft mounting structure, the fan shaft mounting structure comprising at least two bearings connected to or otherwise in engagement with the fan shaft at points spaced apart axially along the length of the engine.
A gas turbine engine for an aircraft comprising:
- an engine core comprising a turbine, a compressor, and a core shaft connecting the turbine to the compressor;
- a fan located upstream of the engine core, the fan comprising a plurality of fan blades;
- and
- a gearbox that is configured to receive an input from the core shaft, and output drive to a fan shaft via an output of the gearbox so as to drive the fan at a lower rotational speed than the core shaft, wherein:
- a fan shaft radial bending stiffness to moment of inertia ratio defined as:
- the
-
- radial
-
- bending
-
- stiffness
-
- of
-
- the
-
- fan
-
- shaft
-
- at
-
- the
-
- output
-
- of
-
- the
-
- gearbox
- the
-
- moment
-
- of
-
- inertia
-
- of
-
- the
-
- fan
- is in a range from 2.5×10−2 Nkg−1m−1mm−2 to 6.0 Nkg−1m−1mm−2;
- and
- each fan blade has a carbon-fibre body with a titanium leading edge.
A gas turbine engine for an aircraft comprising:
- an engine core comprising a turbine, a compressor, and a core shaft connecting the turbine to the compressor;
- a fan located upstream of the engine core, the fan comprising a plurality of fan blades;
- and
- a gearbox that is configured to receive an input from the core shaft, and output drive to a fan shaft via an output of the gearbox so as to drive the fan at a lower rotational speed than the core shaft, wherein:
- a fan shaft radial bending stiffness to moment of inertia ratio defined as:
- the
-
- radial
-
- bending
-
- stiffness
-
- of
-
- the
-
- fan
-
- shaft
-
- at
-
- the
-
- output
-
- of
-
- the
-
- gearbox
- the
-
- moment
-
- of
-
- inertia
-
- of
-
- the
-
- fan
- is in a range from 2.5×10−2 Nkg−1m−1mm−2 to 6.0 Nkg−1m−1mm−2;
- a gear ratio of the gearbox is in a range of 3.2 to 3.8;
- and
- a product of:
- (
- the
-
- radial
-
- bending
-
- stiffness
-
- of
-
- the
-
- fan
-
- shaft
-
- at
-
- the
-
- output
-
- of
-
- the
-
- gearbox
- )
- ×
- (
- the
-
- moment
-
- of
-
- inertia
-
- of
-
- the
-
- fan
- )
- is in a range of 3.0×1014 Nkgmm−2m−1 to 1.4×1018 Nkgmm−2m−1.
Dependencies are inferred from the claim text.