Low pressure ratio fan engine having a dimensional relationship between inlet and fan size

Patent metadata

Field	Value
Publication number	US-9920653-B2
Application number	US-201213721095-A
Country	US
Kind code	B2
Filing date	Dec 20, 2012
Priority date	Dec 20, 2012
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

According to an example embodiment, a gas turbine engine assembly includes, among other things, a fan that has a plurality of fan blades. A diameter of the fan has a dimension D that is based on a dimension of the fan blades. Each fan blade has a leading edge. An inlet portion is situated forward of the fan. A length of the inlet portion has a dimension L between a location of the leading edge of at least some of the fan blades and a forward edge on the inlet portion. A dimensional relationship of L/D is between about 0.2 and 0.45.

First claim

We claim:

1. A gas turbine engine assembly, comprising:
a fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, each fan blade having a leading edge, the fan being configured to deliver a portion of air into a compressor section and a portion of air into a bypass duct, wherein a bypass ratio is greater than 6, the bypass ratio being a ratio of a volume of air passing to the bypass duct compared to a volume of air passing into the compressor section; and
an inlet portion forward of the fan, a length of the inlet portion having a dimension L between a location of the leading edge of at least some of the fan blades and a forward edge on the inlet portion,
wherein a dimensional relationship of L/D is between 0.2 and 0.45.

2. The assembly of claim 1 , wherein the dimensional relationship of L/D is between 0.25 and 0.45.

3. The assembly of claim 2 , wherein the dimensional relationship of L/D is between 0.30 and 0.40.

4. The assembly of claim 2 , wherein the dimensional relationship of L/D is 0.35.

5. The assembly of claim 1 , wherein
the dimension L is different at a plurality of locations on the inlet portion;
a greatest value of L corresponds to a value of L/D that is at most 0.45; and
a smallest value of L corresponds to a value of L/D that is at least 0.20.

6. The assembly of claim 1 , wherein
the dimension L varies; and
the dimensional relationship of L/D is based on an average value of L.

7. The assembly of claim 1 , wherein
the dimension L varies between a top of the inlet portion and a bottom of the inlet portion; and
the dimensional relationship of L/D is based on a value of L near a midpoint between the top and the bottom of the inlet portion.

8. The assembly of claim 1 , wherein
the leading edges of the fan blades are in a reference plane; and
the dimension L extends along a direction that is perpendicular to the reference plane.

9. The assembly of claim 8 , wherein
the engine assembly has a central axis;
the reference plane is perpendicular to the central axis; and
the dimension L extends along a direction that is parallel to the central axis.

10. The assembly of claim 1 , wherein
the engine assembly has a central axis;
the forward edge on the inlet portion is in a first reference plane;
the leading edges of the fan blades are in a second reference plane; and
the dimension L is measured between a first location where the central axis intersects the first reference plane and a second location where the central axis intersects the second reference plane.

11. The assembly of claim 1 , wherein
the fan is a low pressure ratio fan having a pressure ratio between 1.20 and 1.50.

12. The assembly of claim 11 , wherein the bypass ratio is greater than 10.

13. The assembly of claim 1 , wherein
the fan is a low pressure ratio fan having a pressure ratio less than 1.50.

14. The assembly of claim 13 , comprising
a geared architecture configured to drive the fan at a speed that is less than an input speed in the geared architecture, the geared architecture defining a gear reduction ratio greater than or equal to 2.3.

15. A gas turbine engine assembly, comprising:
a fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, each fan blade having a leading edge;
a geared architecture configured to drive the fan at a speed that is less than an input speed in the geared architecture;
a turbine section configured to drive the geared architecture;
an inlet portion forward of the fan, a length of the inlet portion having a dimension L between a location of the leading edge of at least some of the fan blades and a forward edge on the inlet portion; and
wherein a dimensional relationship of L/D is no more than 0.45.

16. The gas turbine engine assembly of claim 15 , wherein
the fan is a low pressure ratio fan having a pressure ratio less than 1.45.

17. The gas turbine engine assembly of claim 15 , wherein
the fan is configured to deliver a portion of air into a compressor section and a portion of air into a bypass duct;
a bypass ratio which is defined as a volume of air passing to the bypass duct compared to a volume of air passing into the compressor section being greater than or equal to 10.

18. The gas turbine engine assembly of claim 15 , wherein a dimensional relationship of L/D is at least 0.20.

19. The gas turbine engine assembly of claim 18 , wherein the dimensional relationship of L/D is between 0.30 and 0.40.

20. The gas turbine engine assembly of claim 15 , wherein the geared architecture defines a gear reduction ratio greater than or equal to 2.3.

Assignees

• United Technologies Corp

Inventors

• Lord Wesley K
• Malecki Robert E
• Qiu Yuan J
• Rose Becky E
• Gilson Jonathan

Classifications

• F05D2250/00

  Geometry · CPC title

• F01D25/24 Primary

  Casings (modified for heating or cooling F01D25/14); Casing parts, e.g. diaphragms, casing fastenings (casings for rotary machines or engines in general F16M {; special arrangements in stators dealing with breaking-off of part of rotor F01D21/045}) · CPC title

• F02K3/06 Primary

  with front fan · CPC title

• F02C7/04

  Air intakes for gas-turbine plants or jet-propulsion plants · CPC title

• F01D17/105

  by passing part of the fluid · CPC title