(19)
(11)EP 2 543 829 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
26.10.2022 Bulletin 2022/43

(21)Application number: 12174433.8

(22)Date of filing:  29.06.2012
(51)International Patent Classification (IPC): 
F01D 25/34(2006.01)
F01D 15/12(2006.01)
F01D 21/04(2006.01)
F02C 7/36(2006.01)
F02K 3/06(2006.01)
F02C 7/05(2006.01)
F01D 5/14(2006.01)
(52)Cooperative Patent Classification (CPC):
F01D 15/12; F01D 25/34; F02C 7/05; F02K 3/06; F01D 5/141; F01D 21/045; F02C 7/36; Y02T 50/60

(54)

Gas turbine propulsor blade with stagger angle for dirt rejection

Schuberzeugerschaufel einer Gasturbine mit Staffelungswinkel zum Schmutzabweis

Aube de propulseur de turbine à gaz avec angle de décalage pour capter de saletés


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 05.07.2011 US 201113176473

(43)Date of publication of application:
09.01.2013 Bulletin 2013/02

(73)Proprietor: Raytheon Technologies Corporation
Farmington, CT 06032 (US)

(72)Inventors:
  • Gallagher, Edward J.
    West Hartford, CT 06107 (US)
  • Rose, Becky E.
    Colchester, CT 06415 (US)
  • Brilliant, Lisa I
    Middletown, CT 06457 (US)

(74)Representative: Dehns 
St. Bride's House 10 Salisbury Square
London EC4Y 8JD
London EC4Y 8JD (GB)


(56)References cited: : 
GB-A- 2 054 058
US-A- 6 071 077
US-A1- 2009 229 242
US-A- 5 299 914
US-A1- 2006 013 692
US-B2- 7 374 403
  
  • William S. Willis: "Quiet Clean Short-Haul Experimental Engine (QCSEE) Final Report", NASA CR-159473, 31 August 1979 (1979-08-31), pages 1-312, XP055305989, Retrieved from the Internet: URL:http://ntrs.nasa.gov/archive/nasa/casi .ntrs.nasa.gov/19800006861.pdf [retrieved on 2016-09-27]
  • Walter M. Osborn ET AL: "Aerodynamic Performance of a 1.35-Pressure-Ratio Axial-Flow Fan Stage", , 31 October 1978 (1978-10-31), pages 1-109, XP055689607, Retrieved from the Internet: URL:https://ntrs.nasa.gov/archive/nasa/cas i.ntrs.nasa.gov/19790001851.pdf [retrieved on 2020-04-27]
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

TECHNICAL FIELD



[0001] This disclosure relates to gas turbine engines and, more particularly, to an engine having a geared turbofan architecture that is designed to operate with a high bypass ratio and a low pressure ratio.

BACKGROUND OF THE INVENTION



[0002] A gas turbine engine of an aircraft often ingests foreign objects, such as particulate matter. The particulate matter may be dirt, sand or the like. If the particulate matter is permitted to pass into the core flow of the engine, it may damage the engine compressor or other downstream engine components.

[0003] A propulsor having the features of the preamble of claim 1 is disclosed in Walter M. Osborn et al: "Aerodynamic Performance of a 1.35-Pressure-Ratio Axial-Flow Fan Stage", 31 October 1978.

[0004] GB 2054058, US 6071077 A and William S. Willis: "Quiet Clean Short-Haul Experimental Engine (QCSEE) Final Report", NASA CR-159473, 31 August 1979, disclose other prior art propulsors.

SUMMARY



[0005] From a first aspect, the invention provides a propulsor for use in a gas turbine engine, as set forth in claim 1.

[0006] From another aspect, the invention provides a gas turbine engine as set forth in claim 10.

BRIEF DESCRIPTION OF THE DRAWINGS



[0007] The various features and advantages of the disclosed examples will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows.

Figure 1 is a schematic cross-section of a gas turbine engine.

Figure 2 is a perspective view of a fan section of the engine of Figure 1.

Figure 3 is an isolated view of a propulsor blade and portion of a hub.

Figure 4 is an axial view of a propulsor blade and portion of a hub.


DETAILED DESCRIPTION



[0008] In a turbofan engine, the fan (e.g., propulsor) is a first line of protection from the ingestion of particulate matter into the core flow of the engine. The fan is designed with blade stagger to induce air swirl that helps move incoming particulate matter into the bypass rather than allow the particulate to enter into the core flow. The blade stagger is typically apparent when viewing the fan axially from the front of the engine. In a turbofan engine architecture where the turbine of the engine directly drives the fan at the same angular speed as the turbine, the stagger angle is severe such that an observer would not be able to see past the fan into the engine because the fan blades are angled with the broad sides turned to the observer.

[0009] The stagger angle may be a function, at least in part, of a variety of factors, such as the number of blades on the fan, the design pressure ratio of the engine, the design bypass ratio of the engine, the solidity of the fan blades and the rotational speed of the fan blades at full throttle as a function of position along the span of the blades.

[0010] As will be described, a disclosed gas turbine engine 20 incorporates a geared architecture and a propulsor 42 that is designed with consideration to at least some of the above factors to achieve a high level of particulate rejection for the geared architecture arrangement and designed operation.

[0011] Figure 1 schematically illustrates the gas turbine engine 20. The gas turbine engine 20 may be a two-spool turbofan that generally incorporates a fan section 22, a compressor section 24, a combustor section 26 and a turbine section 28. Although depicted as a turbofan gas turbine engine, it is to be understood that the concepts described herein are not limited to use with the disclosed arrangement. Alternative engine architectures may include a single-spool design, a three-spool design, or an open rotor design, among other systems or features.

[0012] The fan section 22 drives air along a bypass flow passage B while the compressor section 24 drives air along a core flow passage C for compression and communication into the combustor section 26. An annular splitter 27, located adjacent the fan section 22, generally surrounds the compressor section 24 and establishes the core flow passage C.

[0013] The engine 20 includes a low speed spool 30 and high speed spool 32 mounted for rotation about an engine central longitudinal axis A relative to an engine static structure 36 via several bearing systems 38. The fan section 22 and the compressor section 24 are concentric with the engine central longitudinal axis A. The low speed spool 30 generally includes an inner shaft 40 that is coupled with the propulsor 42, a low pressure compressor 44 and a low pressure turbine 46. The low pressure turbine 46 drives the propulsor 42 through the inner shaft 40 and a gear assembly 48, which allows the low speed spool 30 to drive the propulsor 42 at a different (e.g. lower) angular speed.

[0014] The high speed spool 32 includes an outer shaft 50 that is coupled with a high pressure compressor 52 and a high pressure turbine 54. A combustor 56 is arranged between the high pressure compressor 52 and the high pressure turbine 54. The inner shaft 40 and the outer shaft 50 are concentric and rotate about the engine central longitudinal axis A, which is collinear with their longitudinal axes.

[0015] A core airflow in the core flow passage C is compressed in the low pressure compressor 44 then the high pressure compressor 52, mixed with the fuel and burned in the combustor 56, and then expanded over the high pressure turbine 54 and low pressure turbine 46. The turbines 54, 46 rotationally drive the respective low speed spool 30 and high speed spool 32 in response to the expansion.

[0016] As shown, the propulsor 42 is arranged at an inlet 60 of the bypass flow passage B and the core flow passage C. Air flow through the bypass flow passage B exits the engine 20 through an outlet 62 or nozzle. For a given design of the propulsor 42, the inlet 60 and the outlet 62 establish a design pressure ratio with regard to an inlet pressure at the inlet 60 and an outlet pressure at the outlet 62 of the bypass flow passage B. As an example, the design pressure ratio may be determined based upon the stagnation inlet pressure and the stagnation outlet pressure at a design rotational speed of the engine 20. In that regard, the engine 20 may optionally include a variable area nozzle 64 within the bypass flow passage B. The variable area nozzle 64 is operative to change a cross-sectional area 66 of the outlet 62 to thereby control the pressure ratio via changing pressure within the bypass flow passage B. The design pressure ratio may be defined with the variable area nozzle 64 fully open or fully closed.

[0017] Referring to Figure 2, the propulsor 42, includes a rotor 70 having a row 72 of propulsor blades 74 that extend circumferentially around a hub 76. Each of the propulsor blades 74 extends radially outwardly from the hub 76 between a root 78 and a tip 80, and in a chord direction (axially and circumferentially) between a leading edge 82 and a trailing edge 84. A chord 85 (see Figure 3), also represented by chord dimension (CD), is a straight line that extends between the leading edge 82 and the trailing edge 84 of the propulsor blade 74. The chord dimension (CD) may vary along the span of the propulsor blade 74. For the purpose of later defining solidity, the chord dimension (CD) may be taken at the tips 80 of the propulsor blades 74. The row 72 of propulsor blades 74 also defines a circumferential pitch (CP) that is equivalent to the arc distance between the tips 80 of neighboring propulsor blades 74.

[0018] Figure 3 shows an isolated view of one of the propulsor blades 74 and portion of the hub 76. As shown, the propulsor blade 74 is sectioned at a radial position between the root 78 and the tip 80. The radial position along the propulsor blade 74 can be represented as a percentage of the span of the propulsor blade 74, with the root 78 representing a 0% span and the tip 80 representing a 100% span. The chord 85 is shown on the section of the propulsor blade 74. The chord 85 forms an angle, stagger angle α, with the engine central longitudinal axis A. The stagger angle α can vary with position along the span. The angle can alternatively be represented as an angle between the chord 85 and a line that is orthogonal to the engine central longitudinal axis A, which is equal to 90° - α.

[0019] The stagger angle α of the propulsor blades 74 is designed to facilitate the rejection of particulate matter into the bypass flow passage B for a geared architecture. The gear assembly 48 of the disclosed example permits the propulsor 42 to be driven by the low pressure turbine 46 through the low speed spool 30 at a lower angular speed than the low pressure turbine 46. In embodiments, the stagger angle α of the propulsor blades 74 is designed for effective particulate matter rejection at that lower speed operation.

[0020] Figure 4 shows an axial view of one of the propulsor blades 74 and portion of the hub 76. The stagger angle α within a section of the span of the propulsor blades 74 is designed for the given geared architecture and lower angular speed at full throttle. The stagger angle α is less than 10° within an inboard 20% of the span, represented at 90, with the hub 76 being at 0% of the span and the tip 80 being at 100% of the span. The spatial orientation of the propulsor blades 74 that results from the disclosed stagger angle α increases the probability that incoming particulate matter will strike the propulsor blades 74 and be rejected into the bypass flow passage B rather than the core flow passage C.

[0021] In a further embodiment, the stagger angle α is less than 5° within the inboard 20% of the span or the range of 5%-15% span. In some embodiments, the chord 85 may be substantially parallel to the engine longitudinal central axis A (e.g., within +/-2°) such that the stagger angle α is approximately 0° within the inboard 20% of the span or the range of 5%-15% span.

[0022] The stagger angle α may also be described with regard to the location of the annular splitter 27. The annular splitter 27 is spaced a radial distance (D) from the engine longitudinal central axis. The disclosed stagger angles α may be at a position along the propulsor blade 74 that is radially inward of the radial distance (D).

[0023] In general, the selected stagger angle α may follow an inverse relationship to the design bypass ratio of the engine 20 with regard to the amount of air that passes through the bypass flow passage B and the amount of air that passes through the core flow passage C such that lower stagger angles correspond to higher bypass ratio designs, and vice versa. In embodiments, the stagger angle α may be less than 5° for a design bypass ratio of 18.

[0024] As described, the stagger angle α may also be a function, at least in part, of the number of blades, the design pressure ratio, the design bypass ratio, and the solidity of the blades. In that regard, embodiments of the propulsor blades 74 may also have some or all of the below-described properties in combination with the disclosed stagger angles α.

[0025] In embodiments, the propulsor 42 may include a number (N) of the propulsor blades 74 in the row 72 that is no more than 20. For instance, the number N may be any number from 10 to 20.

[0026] Additionally, the propulsor blades 74 define a solidity value with regard to the chord dimension CD at the tips 80 and the circumferential pitch CP. The solidity value is defined as a ratio (R) of CD/CP (i.e., CD divided by CP). In embodiments, the solidity value of the propulsor 42 is between 0.6 and 1.3.

[0027] The engine 20 may also be designed with a particular design pressure ratio. In embodiments, the design pressure ratio may be between 1.1 and 1.55.

[0028] The engine 20 may also be designed with a particular bypass ratio with regard to the amount of air that passes through the bypass flow passage B and the amount of air that passes through the core flow passage C. As an example, the design bypass ratio of the engine 20 may nominally be 12 or greater.

[0029] The propulsor 42 also defines a ratio of N/R. In embodiments, the ratio N/R is between 8 and 28. Tables 1 and 2 below show additional examples of solidity and the ratio N/R for different numbers of propulsor blades 74 that can be used with the disclosed stagger angles α.
TABLE 1: Number of Blades, Solidity and Ratio N/R
Number of Blades (N)SolidityRatio N/R
20 1.3 15.4
18 1.3 13.8
16 1.3 12.3
14 1.3 10.8
12 1.3 9.2
20 1.2 16.7
18 1.2 15.0
16 1.2 13.3
14 1.2 11.7
12 1.2 10.0
20 1.1 18.2
18 1.1 16.4
16 1.1 14.5
14 1.1 12.7
12 1.1 10.9
20 1.0 20.0
18 1.0 18.0
16 1.0 16.0
14 1.0 14.0
12 1.0 12.0
TABLE 2: Number of Blades, Solidity and Ratio N/R
Number of Blades (N)SolidityRatio N/R
16 1.1 14.5
14 1.1 12.7
12 1.1 10.9
10 1.1 9.1
16 1.02 15.7
14 1.02 13.7
12 1.02 11.8
10 1.02 9.8
16 0.89 18.0
14 0.89 15.7
12 0.89 13.5
10 0.89 11.2
16 0.76 21.1
14 0.76 18.4
12 0.76 15.8
10 0.76 13.2
16 0.63 25.4
14 0.63 22.2
12 0.63 19.0
10 0.63 15.9
16 0.60 26.7
14 0.60 23.3
12 0.60 20.0
10 0.60 16.7


[0030] The disclosed ratios of N/R also enhance the propulsive efficiency of the disclosed engine 20. For instance, the disclosed ratios of N/R are designed for the geared turbofan architecture of the engine 20 that utilizes the gear assembly 48. That is, the gear assembly 48 allows the propulsor 42 to rotate at a different, lower speed than the low speed spool 30. In combination with the variable area nozzle 64, the propulsor 42 can be designed with a large diameter and rotate at a relatively slow speed with regard to the low speed spool 30. A relatively low speed, relatively large diameter, and the geometry that permits the disclosed ratios of N/R contribute to the reduction of performance debits, such as by lowering the speed of the air or fluid that passes over the propulsor blades 74.

[0031] Although a combination of features is shown in the illustrated examples, not all of them need to be combined to realize the benefits of various embodiments of this disclosure. In other words, a system designed according to an embodiment of this disclosure will not necessarily include all of the features shown in any one of the Figures or all of the portions schematically shown in the Figures. Moreover, selected features of one example embodiment may be combined with selected features of other example embodiments.

[0032] The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this disclosure. The scope of legal protection given to this disclosure can only be determined by studying the following claims.


Claims

1. A propulsor (42) for use in a gas turbine engine (20), the propulsor comprising:

a rotor including a row of propulsor blades (74) extending from a hub (76) that is rotatable around an axis (A), each of said propulsor blades (74) has a span between a root (78) at said hub (76) and a tip (80), and a chord (85) between a leading edge (82) and a trailing edge (84) such that said chord (85) forms a stagger angle α with said axis (A), wherein said hub (76) is at 0% of said span and said tip (80) is at 100% of said span;

characterised in that:
the stagger angle α is less than 10° within an inboard 20% of the span.


 
2. The propulsor as recited in claim 1, wherein said stagger angle α is less than 5° within the inboard 20% of the span.
 
3. The propulsor as recited in claim 1, wherein said stagger angle α is less than 5° within the range of 5%-15% span.
 
4. The propulsor as recited in claim 1, wherein said chord (85) is substantially parallel to said axis (A) such that the stagger angle α is approximately 0° within the inboard 20% of the span.
 
5. The propulsor as recited in claim 1, wherein said chord (85) is substantially parallel to said axis (A) such that the stagger angle α is approximately 0° within the range of 5%-15% span.
 
6. The propulsor as recited in any preceding claim, wherein said chord (85) has a chord dimension (CD) at said tips (80), said row of propulsor blades (74) defines a circumferential pitch (CP) with regard to said tips (80), and said row of propulsor blades (74) has a solidity value (R) defined as CD/CP that is between 0.6 and 1.3.
 
7. The propulsor as recited in any preceding claim, wherein said row of propulsor blades (74) includes a number (N) of said propulsor blades (74) that is no more than 20.
 
8. The propulsor as recited in any preceding claim, wherein said chord (85) has a chord dimension (CD) at said tips (80), said row of propulsor blades (74) defines a circumferential pitch (CP) with regard to said tips (80), said row of propulsor blades (74) has a solidity value (R) defined as CD/CP, and said row of propulsor blades (74) includes a number (N) of said propulsor blades (74) that is no more than 20 such that a ratio of N/R is between 8 and 28.
 
9. The propulsor as recited in any preceding claim, wherein said stagger angle α varies with position of said chord (85) along said span.
 
10. A gas turbine engine (20) comprising:

a spool (30);

a turbine (46) coupled with said spool (30);

a propulsor (42) as recited in any preceding claim coupled to be rotated about an axis by said turbine (46) through said spool (30); and

a gear assembly (48) coupled between said propulsor (42) and said spool (30) such that rotation of said turbine (46) drives said propulsor (42) at a different speed than said spool (30).


 
11. The gas turbine engine as recited in claim 10, wherein said propulsor (42) is located at an inlet of a bypass flow passage (B) having a design pressure ratio that is between 1.1 and 1.55 with regard to an inlet pressure and an outlet pressure of said bypass flow passage (B).
 
12. The gas turbine engine (20) as recited in claim 10, comprising:
a compressor section (24) that extends along a central axis (A) and includes an annular splitter (27) spaced a radial distance (D) from said central axis (A) such that there is a core flow radially inward of said annular splitter (27) and a bypass flow radially outward of said annular splitter (27); wherein said propulsor (42) is adjacent said compressor section (24) and said stagger angle α is less than 10° radially inward of said radial distance (D).
 
13. The gas turbine engine (20) as recited in claim 10, comprising:
a compressor section (24) that extends along a central axis (A) and includes an annular splitter (27) spaced a radial distance (D) from said central axis (A) such that there is a core flow radially inward of said annular splitter (27) and a bypass flow radially outward of said annular splitter (27); wherein said propulsor (42) is adjacent said compressor section (24) and said stagger angle α is less than 5° radially inward of said radial distance (D).
 
14. The gas turbine engine as recited in claim 12 or 13, including a design bypass ratio with regard to said bypass flow and said core flow that is at least 12.
 


Ansprüche

1. Schuberzeuger (42) zur Verwendung in einem Gasturbinenmotor (20), wobei der Schuberzeuger Folgendes umfasst:

einen Rotor, der eine Reihe von Schuberzeugerschaufeln (74) beinhaltet, die sich von einer Nabe (76) erstrecken, die um eine Achse (A) drehbar ist, wobei jede der Schuberzeugerschaufeln (74) eine Spanne zwischen einem Fuß (78) an der Nabe (76) und einer Spitze (80) sowie eine Sehne (85) zwischen einer Vorderkante (82) und einer Hinterkante (84) aufweist, derart, dass die Sehne (85) einen Staffelungswinkel α mit der Achse (A) bildet, wobei die Nabe (76) bei 0 % der Spanne liegt und die Spitze (80) bei 100 % der Spanne liegt;

dadurch gekennzeichnet, dass:
der Staffelungswinkel α in innenliegenden 20 % der Spanne weniger als 10° beträgt.


 
2. Schuberzeuger nach Anspruch 1, wobei der Staffelungswinkel α in innenliegenden 20 % der Spanne weniger als 5° beträgt.
 
3. Schuberzeuger nach Anspruch 1, wobei der Staffelungswinkel α im Bereich von 5 % - 15 % der Spanne weniger als 5° beträgt.
 
4. Schuberzeuger nach Anspruch 1, wobei die Sehne (85) im Wesentlichen parallel zur Achse (A) verläuft, derart, dass der Staffelungswinkel α in den innenliegenden 20 % der Spanne etwa 0° beträgt.
 
5. Schuberzeuger nach Anspruch 1, wobei die Sehne (85) im Wesentlichen parallel zur Achse (A) verläuft, derart, dass der Staffelungswinkel α im Bereich von 5 % - 15 % der Spanne etwa 0° beträgt.
 
6. Schuberzeuger nach einem der vorhergehenden Ansprüche, wobei die Sehne (85) an den Spitzen (80) eine Sehnendimension (CD) aufweist, die Reihe von Schuberzeugerschaufeln (74) mit Bezug auf die Spitzen (80) eine Umfangsteilung (CP) definiert und die Reihe von Schuberzeugerschaufeln (74) einen Stabilitätswert (R), der als CD/CP definiert ist, zwischen 0,6 und 1,3 aufweist.
 
7. Schuberzeuger nach einem der vorhergehenden Ansprüche, wobei die Reihe von Schuberzeugerschaufeln (74) eine Anzahl (N) der Schuberzeugerschaufeln (74) beinhaltet, die nicht mehr als 20 beträgt.
 
8. Schuberzeuger nach einem der vorhergehenden Ansprüche, wobei die Sehne (85) an den Spitzen (80) eine Sehnendimension (CD) aufweist, die Reihe von Schuberzeugerschaufeln (74) mit Bezug auf die Spitzen (80) eine Umfangsteilung (CP) definiert, die Reihe von Schuberzeugerschaufeln (74) einen Stabilitätswert (R) aufweist, der als CD/CP definiert ist, und die Reihe von Schuberzeugerschaufeln (74) eine Anzahl (N) der Schuberzeugerschaufeln (74) beinhaltet, die nicht mehr als 20 beträgt, derart, dass ein Verhältnis von N/R zwischen 8 und 28 beträgt.
 
9. Schuberzeuger nach einem der vorhergehenden Ansprüche, wobei der Staffelungswinkel α mit der Position der Sehne (85) entlang der Spanne variiert.
 
10. Gasturbinenmotor (20), der Folgendes umfasst:

eine Welle (30);

eine Turbine (46), die an die Welle (30) gekoppelt ist;

einen Schuberzeuger (42) nach einem der vorhergehenden Ansprüche, der gekoppelt ist, um durch die Turbine (46) mittels der Welle (30) um eine Achse gedreht zu werden; und

eine Getriebeanordnung (48), die zwischen dem Schuberzeuger (42) und der Welle (30) gekoppelt ist, derart, dass eine Drehung der Turbine (46) den Schuberzeuger (42) mit einer anderen Geschwindigkeit als die Welle (30) antreibt.


 
11. Gasturbinenmotor nach Anspruch 10, wobei sich der Schuberzeuger (42) an einem Einlass einer Bypassflussdurchführung (B) befindet, die ein konzipiertes Druckverhältnis aufweist, das mit Bezug auf einen Einlassdruck und einen Auslassdruck der Bypassflussdurchführung (B) zwischen 1,1 und 1,55 liegt.
 
12. Gasturbinenmotor (20) nach Anspruch 10, der ferner Folgendes umfasst:
einen Verdichterabschnitt (24), der sich entlang einer Mittelachse (A) erstreckt und einen ringförmigen Teiler (27) beinhaltet, der in einem radialen Abstand (D) von der Mittelachse (A) beabstandet ist, derart, dass es auf der radialen Innenseite des ringförmigen Teilers (27) einen Kernfluss und auf der radialen Außenseite des ringförmigen Teilers (27) einen Bypassfluss gibt; wobei der Schuberzeuger (42) dem Verdichterabschnitt (24) benachbart ist und der Staffelungswinkel α auf der radialen Innenseite des radialen Abstands (D) weniger als 10° beträgt.
 
13. Gasturbinenmotor (20) nach Anspruch 10, der ferner Folgendes umfasst:
einen Verdichterabschnitt (24), der sich entlang einer Mittelachse (A) erstreckt und einen ringförmigen Teiler (27) beinhaltet, der in einem radialen Abstand (D) von der Mittelachse (A) beabstandet ist, derart, dass es auf der radialen Innenseite des ringförmigen Teilers (27) einen Kernfluss und auf der radialen Außenseite des ringförmigen Teilers (27) einen Bypassfluss gibt; wobei der Schuberzeuger (42) dem Verdichterabschnitt (24) benachbart ist und der Staffelungswinkel α auf der radialen Innenseite des radialen Abstands (D) weniger als 5° beträgt.
 
14. Gasturbinenmotor nach Anspruch 12 oder 13, der mit Bezug auf den Bypassfluss und den Kernfluss ein konzipiertes Bypassverhältnis beinhaltet, das mindestens 12 beträgt.
 


Revendications

1. Propulseur (42) destiné à être utilisé dans un moteur à turbine à gaz (20), le propulseur comprenant :

un rotor comportant une rangée de pales de propulseur (74) s'étendant à partir d'un moyeu (76) qui peut tourner autour d'un axe (A), chacune desdites pales de propulseur (74) ayant une envergure entre un pied (78) au niveau dudit moyeu (76) et une pointe (80), et une corde (85) entre un bord d'attaque (82) et un bord de fuite (84) de sorte que ladite corde (85) forme un angle de décalage α avec ledit axe (A), dans lequel ledit moyeu (76) se trouve à 0 % de ladite envergure et de ladite pointe (80) se trouve à 100 % de ladite envergure ;

caractérisé en ce que :
l'angle de décalage α est inférieur à 10° à 20 % de l'intérieur de l'envergure.


 
2. Propulseur selon la revendication 1, dans lequel ledit angle de décalage α est inférieur à 5° à 20 % de l'intérieur de l'envergure.
 
3. Propulseur selon la revendication 1, dans lequel ledit angle de décalage α est inférieur à 5° dans la plage de 5 % à 15 % d'envergure.
 
4. Propulseur selon la revendication 1, dans lequel ladite corde (85) est sensiblement parallèle audit axe (A) de sorte que l'angle de décalage α soit d'environ 0° à 20 % de l'intérieur de l'envergure.
 
5. Propulseur selon la revendication 1, dans lequel ladite corde (85) est sensiblement parallèle audit axe (A) de sorte que l'angle de décalage α soit d'environ 0° dans la plage de 5 % à 15 % d'envergure.
 
6. Propulseur selon une quelconque revendication précédente, dans lequel ladite corde (85) a une dimension de corde (CD) au niveau desdites pointes (80), ladite rangée de pales de propulseur (74) définit un pas circonférentiel (CP) par rapport auxdites pointes (80), et ladite rangée de pales de propulseur (74) a une valeur de solidité (R) définie par CD/CP comprise entre 0,6 et 1,3.
 
7. Propulseur selon une quelconque revendication précédente, dans lequel ladite rangée de pales de propulseur (74) comprend un nombre (N) desdites pales de propulseur (74) qui n'est pas supérieur à 20.
 
8. Propulseur selon une quelconque revendication précédente, dans lequel ladite corde (85) a une dimension de corde (CD) au niveau desdites pointes (80), ladite rangée de pales de propulseur (74) définit un pas circonférentiel (CP) par rapport auxdites pointes (80), ladite rangée de pales de propulseur (74) a une valeur de solidité (R) définie par CD/CP, et ladite rangée de pales de propulseur (74) comporte un nombre (N) desdites pales de propulseur (74) qui n'est pas supérieur à 20 de sorte qu'un rapport de N/R soit compris entre 8 et 28.
 
9. Propulseur selon une quelconque revendication précédente, dans lequel ledit angle de décalage α varie avec la position de ladite corde (85) le long de ladite envergure.
 
10. Moteur à turbine à gaz (20) comprenant :

une bobine (30) ;

une turbine (46) couplée à ladite bobine (30) ;

un propulseur (42) selon une quelconque revendication précédente couplé de manière à être mis en rotation, autour d'un axe, par ladite turbine (46) par l'intermédiaire de ladite bobine (30) ; et

un ensemble d'engrenages (48) couplé entre ledit propulseur (42) et ladite bobine (30) de sorte que la rotation de ladite turbine (46) entraîne ledit propulseur (42) à une vitesse différente de celle de ladite bobine (30).


 
11. Moteur à turbine à gaz selon la revendication 10, dans lequel ledit propulseur (42) est situé à une entrée d'un passage d'écoulement de dérivation (B) ayant un rapport de pression de conception compris entre 1,1 et 1,55 par rapport à une pression d'entrée et une pression de sortie dudit passage d'écoulement de dérivation (B).
 
12. Moteur à turbine à gaz (20) selon la revendication 10, comprenant :

une section de compresseur (24) qui s'étend le long d'un axe central (A) et comporte un séparateur annulaire (27) espacé d'une distance radiale (D) dudit axe central (A) de sorte qu'il existe un écoulement central radialement vers l'intérieur dudit séparateur annulaire (27) et un écoulement de dérivation radialement vers l'extérieur dudit séparateur annulaire (27) ;

dans lequel ledit propulseur (42) est adjacent à ladite section de compresseur (24) et ledit angle de décalage α est inférieur à 10° radialement vers l'intérieur de ladite distance radiale (D) .


 
13. Moteur à turbine à gaz (20) selon la revendication 10, comprenant :

une section de compresseur (24) qui s'étend le long d'un axe central (A) et comporte un séparateur annulaire (27) espacé d'une distance radiale (D) dudit axe central (A) de sorte qu'il existe un écoulement central radialement vers l'intérieur dudit séparateur annulaire (27) et un écoulement de dérivation radialement vers l'extérieur dudit séparateur annulaire (27) ;

dans lequel ledit propulseur (42) est adjacent à ladite section de compresseur (24) et ledit angle de décalage α est inférieur à 5° radialement vers l'intérieur de ladite distance radiale (D) .


 
14. Moteur à turbine à gaz selon la revendication 12 ou 13, ayant un taux de dérivation de conception par rapport audit écoulement de dérivation et audit écoulement central qui est d'au moins 12.
 




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Cited references

REFERENCES CITED IN THE DESCRIPTION



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Patent documents cited in the description




Non-patent literature cited in the description