Overall Engine Efficiency Rating for Turbomachine Engines

Patent metadata

Field	Value
Publication number	US-2025250942-A1
Application number	US-202418603880-A
Country	US
Kind code	A1
Filing date	Mar 13, 2024
Priority date	Jan 31, 2022
Publication date	Aug 7, 2025
Grant date	—

Abstract

A turbomachine engine can include a fan assembly, a vane assembly, a core engine, a gearbox, and an overall engine efficiency rating. The fan assembly can include a plurality of fan blades. The vane assembly can include a plurality of vanes, and the vanes can, in some instances, be disposed aft of the fan blades. The core engine can include a low-pressure turbine. The gearbox includes an input and an output. The input of the gearbox is coupled to the low-pressure turbine of the core engine and comprises a first rotational speed, the output of the gearbox is coupled to the fan assembly and has a second rotational speed, and a gear ratio of the first rotational speed to the second rotational speed is within a range of 2.0-4.0.

First claim

1 . A turbomachine engine comprising:
a fan assembly including a plurality of fan blades; a vane assembly including a plurality of vanes disposed aft of the plurality of fan blades; a core engine including a low-pressure turbine; a gearbox including an input, an output, and a gear ratio (GR), wherein the gearbox is a multi-stage gearbox, wherein the input of the gearbox is coupled to the low-pressure turbine of the core engine, wherein the output of the gearbox is coupled to the fan assembly, and wherein the GR is within a range of 2.0-4.0; and an overall engine efficiency rating greater than or equal to 1.9 and less than or equal to GR 1.5 , wherein the overall engine efficiency rating equals

Q
⁢

(

D
1.56

T

)

1
.
5

⁢
3

⁢

N
2

,

wherein Q is a gearbox oil flow rate at an inlet of the gearbox measured in gallons per minute at a max takeoff condition, wherein D is a diameter of the fan blades measured in inches, wherein T is a net thrust of the turbomachine engine measured in pounds force at the max takeoff condition, and wherein N is a number of rotating blade stages of the low-pressure turbine.

2 . The turbomachine engine of claim 1 , wherein the gearbox is a two-stage gearbox.

3 . The turbomachine engine of claim 1 , further comprising a combustor disposed aft of the fan assembly and forward of the low-pressure turbine, wherein the gearbox is located forward from the combustor.

4 . The turbomachine engine of claim 1 , further comprising a combustor disposed aft of the fan assembly and forward of the low-pressure turbine, wherein the gearbox is located aft of the combustor.

5 . The turbomachine engine of claim 1 , wherein the gearbox is a compound gearbox.

6 . The turbomachine engine of claim 5 , wherein the compound gearbox comprises one or more compound gears, wherein each of the one or more compound gears includes a first portion having a first diameter and a second portion having a second diameter, the second diameter being less than the first diameter.

7 . The turbomachine engine of claim 1 , wherein the N is exactly three rotating blade stages.

8 . The turbomachine engine of claim 1 , wherein the N is exactly four rotating blade stages.

9 . The turbomachine engine of claim 1 , wherein the N is exactly five rotating blade stages.

10 . A turbomachine engine comprising:
a fan assembly including a plurality of fan blades; a vane assembly including a plurality of vanes disposed aft of the plurality of fan blades; a core engine including a low-pressure turbine; a gearbox including an input, an output, and a gear ratio (GR), wherein the gearbox is a multi-stage gearbox, wherein the input of the gearbox is coupled to the low-pressure turbine of the core engine, wherein the output of the gearbox is coupled to the fan assembly, and wherein the GR is within a range of 3.2-4.0; and an overall engine efficiency rating greater than or equal to 0.1GR 1.5 and less than or equal to GR 1.5 , wherein the overall engine efficiency rating equals

Q
⁢

(

D
1.56

T

)

1
.
5

⁢
3

⁢

N
2

,

wherein Q is a gearbox oil flow rate at an inlet of the gearbox measured in gallons per minute at a max takeoff condition, wherein D is a diameter of the fan blades measured in inches, wherein T is a net thrust of the turbomachine engine measured in pounds force at the max takeoff condition, and wherein N is a number of rotating blade stages of the low-pressure turbine.

11 . The turbomachine engine of claim 10 , wherein the gearbox is a two-stage gearbox.

12 . The turbomachine engine of claim 10 , further comprising a combustor disposed aft of the fan assembly and forward of the low-pressure turbine, wherein the gearbox is located forward from the combustor.

13 . The turbomachine engine of claim 10 , further comprising a combustor disposed aft of the fan assembly and forward of the low-pressure turbine, wherein the gearbox is located aft of the combustor.

14 . The turbomachine engine of claim 10 , wherein the gearbox is a compound gearbox.

15 . The turbomachine engine of claim 10 , wherein the N is exactly four rotating blade stages.

16 . A turbomachine engine comprising:
a fan assembly including a plurality of fan blades; a vane assembly including a plurality of vanes disposed aft of the plurality of fan blades; a core engine including a low-pressure turbine; a gearbox including an input, an output, and a gear ratio (GR), wherein the gearbox is a multi-stage gearbox, wherein the input of the gearbox is coupled to the low-pressure turbine of the core engine, wherein the output of the gearbox is coupled to the fan assembly, and wherein the GR is within a range of 3.2-4.0; and an overall engine efficiency rating greater within a range of 0.57-8.0, wherein the overall engine efficiency rating equals

Q
⁢

(

D
1.56

T

)

1
.
5

⁢
3

⁢

N
2

,

wherein Q is a gearbox oil flow rate at an inlet of the gearbox measured in gallons per minute at a max takeoff condition, wherein D is a diameter of the fan blades measured in inches, wherein T is a net thrust of the turbomachine engine measured in pounds force at the max takeoff condition, and wherein N is a number of rotating blade stages of the low-pressure turbine.

17 . The turbomachine engine of claim 16 , wherein the gearbox is a two-stage gearbox.

Assignees

• Gen Electric
• Ge Avio Srl

Inventors

• Piazza Andrea
• Clements Jeffrey D

Classifications

• F05D2260/98

  Lubrication · CPC title

• F05D2260/40311

  of the epicyclical, planetary or differential type · CPC title

• F05D2200/221

  Square power · CPC title

• F05D2200/14

  Division · CPC title

• F05D2200/13

  Product · CPC title