Gas turbine engine

Patent metadata

Field	Value
Publication number	US-12577926-B2
Application number	US-202519043121-A
Country	US
Kind code	B2
Filing date	Jan 31, 2025
Priority date	Aug 2, 2022
Publication date	Mar 17, 2026
Grant date	Mar 17, 2026

Abstract

A gas turbine engine includes a turbomachine defining an engine inlet to an inlet duct, a fan duct inlet to a fan duct, and a core inlet to a core duct; a primary fan driven by the turbomachine; a nacelle surrounding the primary fan; and a secondary fan located downstream of the primary fan within the inlet duct. The gas turbine engine is characterized by a thrust to power airflow ratio, a core bypass ratio, a blade effective acoustic length, an acoustic spacing length, and an inlet-to-nacelle ratio.

First claim

We claim:

1 . A gas turbine engine comprising:
a turbomachine comprising a compressor section, a combustion section, and a turbine section arranged in serial flow order, the turbomachine defining an engine inlet to an inlet duct, a fan duct inlet to a fan duct, and a core inlet to a core duct; a primary fan driven by the turbomachine and comprising a plurality of primary fan blades; an outer nacelle surrounding the primary fan; a secondary fan located downstream of the primary fan within the inlet duct; and a plurality of outlet guide vanes disposed aft of the primary fan; a blade effective acoustic length (BEAL) defined as:

BEAL
=

2
⁢

c
2

S
⁡
(

1
-

r
⁢
r

)

⁢

N
b

⁢
c
⁢

os
⁢

(
γ
)

wherein c is a chord length of a primary fan blade of the plurality of primary fan blades, S is a span of the primary fan blade, rr is a radius ratio of the primary fan, γ is a stagger angle of the primary fan blade, and Nb is a number of the plurality of primary fan blades;
an inlet-to-nacelle (ITN) ratio between 0.23 and 0.35; and
an acoustic spacing ratio (ASR) between 1.5 and 16.0, wherein the acoustic spacing ratio is defined as:

ASR
=

1

(

N
⁢
v

N
⁢
b

)

·

A
⁢
s

B
⁢
E
⁢
A
⁢
L

wherein As is the acoustic spacing and Nv is a number of the plurality of outlet guide vanes,
wherein the gas turbine engine defines a thrust to power airflow ratio between 3.5 and 100 and a core bypass ratio between 0.1 and 10,
wherein the thrust to power airflow ratio is a ratio of an airflow through a bypass passage over the turbomachine plus an airflow through the fan duct to an airflow through the core duct,
wherein the core bypass ratio is a ratio of the airflow through the fan duct to the airflow through the core duct, and
wherein the ITN ratio is a ratio of an inlet length to a maximum diameter of the outer nacelle.

2 . The gas turbine engine of claim 1 , wherein the thrust to power airflow ratio and the core bypass ratio are defined when the gas turbine engine is operated at a rated speed during standard day operating conditions.

3 . The gas turbine engine of claim 1 , wherein the thrust to power airflow ratio is between 4 and 75.

4 . The gas turbine engine of claim 1 , wherein the thrust to power airflow ratio is between 20 and 35.

5 . The gas turbine engine of claim 4 , further comprising an inlet length ratio, wherein:
the inlet length ratio is a ratio of an inlet length to a diameter of the primary fan blade of the plurality of primary fan blades, wherein the inlet length is an average distance from a leading edge of the fan blade to an inlet of the outer nacelle, and wherein the inlet length ratio is between 0.15 and 0.4.

6 . The gas turbine engine of claim 4 , wherein the outer nacelle comprises an acoustic treatment.

7 . The gas turbine engine of claim 6 , wherein the acoustic treatment is disposed on an interior surface of the outer nacelle between the primary fan and the plurality of outlet guide vanes.

8 . The gas turbine engine of claim 1 , wherein the thrust to power airflow ratio is between 3.5 and 40.

9 . The gas turbine engine of claim 1 , wherein the thrust to power airflow ratio is between 8 and 40.

10 . The gas turbine engine of claim 1 , wherein the radius ratio is between 0.2 and 0.35.

11 . The gas turbine engine of claim 10 , wherein the radius ratio is between 0.25 and 0.35.

12 . The gas turbine engine of claim 1 , wherein the number of the plurality of primary fan blades (N b ) is between 14 and 26.

13 . The gas turbine engine of claim 1 , further comprising a disk-to-nacelle diametric (DND) ratio defined as a ratio of a disk spacing length to the fan diameter, the disk spacing length being a distance between a forwardmost end of a fan disk and an intersection with the inlet taken along an engine centerline, wherein the DND ratio of the gas turbine engine is 0.07 to 0.47.

14 . The gas turbine engine of claim 1 , further comprising a disk-to-inlet length (DIL) ratio defined as a ratio of a disk spacing length to the fan diameter, the disk spacing length being a distance between a forwardmost end of a fan disk and an intersection with the inlet taken along an engine centerline, wherein the DIL ratio of the gas turbine engine is 0.30 to 0.80.

15 . The gas turbine engine of claim 1 , wherein the primary fan has a diameter between 80 inches and 95 inches.

16 . The gas turbine engine of claim 1 , further comprising a disk-to-blade diametric (DBD) ratio defined as a ratio of a disk spacing length to the fan diameter, the disk spacing length being a distance between a forwardmost end of a fan disk and an intersection with the inlet taken along an engine centerline, and wherein the DBD ratio of the gas turbine engine is 0.09 to 0.59.

17 . The gas turbine engine of claim 1 , further comprising a gearbox assembly coupling the turbine section to the primary fan.

18 . The gas turbine engine of claim 1 , wherein the gas turbine engine further defines a bypass passage outlet at a downstream end of the outer nacelle, wherein the fan duct defines a fan duct outlet, and wherein the fan duct outlet is downstream of the bypass passage outlet.

19 . The gas turbine engine of claim 1 , wherein the gas turbine engine further defines a bypass passage outlet at a downstream end of the outer nacelle, wherein the fan duct defines a fan duct outlet, and wherein the fan duct outlet is upstream of the bypass passage outlet.

20 . The

Assignees

• Gen Electric

Inventors

• Miller Brandon W
• Vondrell Randy M
• Ostdiek David M
• Higgins Craig W
• Simpson Alexander
• Sibbach Arthur W

Classifications

• F02C3/06

  the compressor comprising only axial stages (F02C3/10 takes precedence) · CPC title

• Y02T50/60

  Efficient propulsion technologies, e.g. for aircraft · CPC title

• F05D2260/96

  Preventing, counteracting or reducing vibration or noise · CPC title

• F05D2260/961

  by mistuning rotor blades or stator vanes with irregular interblade spacing, airfoil shape · CPC title

• F02K3/077

  the plant being of the multiple flow type, i.e. having three or more flows · CPC title