US20010014285A1 - Rotor blade an axial-flow engine - Google Patents
Rotor blade an axial-flow engine Download PDFInfo
- Publication number
- US20010014285A1 US20010014285A1 US09/424,481 US42448100A US2001014285A1 US 20010014285 A1 US20010014285 A1 US 20010014285A1 US 42448100 A US42448100 A US 42448100A US 2001014285 A1 US2001014285 A1 US 2001014285A1
- Authority
- US
- United States
- Prior art keywords
- blade
- edge
- airfoil
- afflux
- rotor blade
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/141—Shape, i.e. outer, aerodynamic form
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/32—Rotors specially for elastic fluids for axial flow pumps
- F04D29/321—Rotors specially for elastic fluids for axial flow pumps for axial flow compressors
- F04D29/324—Blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2250/00—Geometry
- F05D2250/70—Shape
- F05D2250/71—Shape curved
- F05D2250/713—Shape curved inflexed
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T50/00—Aeronautics or air transport
- Y02T50/60—Efficient propulsion technologies, e.g. for aircraft
Definitions
- This invention relates to a rotor blade airfoil of an axial-flow turbomachine, more particularly for a fan or a compressor high-pressure stage of a gas turbine system, having means in the tip area to improve supersonic performance.
- a rotor blade airfoil of an axial-flow turbomachine more particularly for a fan or a compressor high-pressure stage of a gas turbine system, having means in the tip area to improve supersonic performance.
- Associated state of the art is described in U.S. Pat. No. 3,989,406 and U.S. Pat. No. 4,012,172.
- the first-cited patent specification deals with the supersonic performance of rotor blade airfoils generally, while the second illustrates a forward swept airfoil, i.e.
- the present invention also relates to the sweep of rotor blade airfoils, more particularly of the first compressor high-pressure stages or of a fan of gas turbines or aircraft gas turbine engines. Owing to the high peripheral speeds of said components and the practically zero-swirl inlet flow to the blade, supersonic regions occur in the blade tip area with mach numbers in excess of 1.4. These for several reasons negatively affect the performance of this component. Firstly, the efficiency decreases with increasing blade span, owing to growing shock losses, much more severely than with subsonic rotors. Also, the interaction of duct shock with blade tip swirl negatively affects the stability of the flow, because large blockage regions occur in that area whose nonlinear growth ultimately determines the stability limit of the compressor.
- the arrangement of the present invention provides means to remedy said problems.
- Reference numeral 1 indicates the blade root and reference numeral 2 the airfoil of the rotor blade of an axial-flow turbomachine, more particularly for a fan or compressor high-pressure stage of a gas turbine system.
- the axis of rotation of the rotor omitted on the drawing, accordingly runs parallel to the direction of flow 3 and extends (far) below the blade root 1 .
- airfoil 2 has a root region 2 a and a tip region 2 b , the latter substantially extending along the outer 15% to 25%, more particularly along about 20% of the blade span h.
- the latter by amount is the difference (R a ⁇ R i ), where R a is the outer radius measured from the axis of rotation and R i the inner radius of the airfoil 2 .
- Shown in the tip region 2 b is both the afflux edge 4 a and the efflux edge 4 b of a conventionally designed airfoil 2 , indicated by dashed lines a′ and b′.
- a conventionally shaped airfoil of this type is impaired by the disadvantages cited above.
- the airfoil 2 of the present invention is in the tip region 2 b provided with a forward-back sweep at least on the blade afflux edge 4 a as shown on the drawing, i.e. in this tip region 2 b the blade afflux edge 4 a extends, unlike in a conventional design, first counter to the direction of flow 3 and, upon reaching a radius point U, retreats in the direction of flow 3 in a manner more pronounced than with a conventionally designed blade afflux edge a′.
- an angle ⁇ of a 90° order of magnitude is sought in the uppermost region, i.e. at the blade tip, between the afflux edge 4 a and the case contour indicated by line 5 of a case (omitted on the drawing) surrounding the rotor.
- the blade efflux edge 4 b has a shape essentially similar to that of the blade afflux edge 4 a , i.e. it reflects the forward-back sweep, as a comparison of the solid line 4 b with the line b′ representing the conventional design will show.
- the back sweep can be made more pronounced than the forward sweep, so as to allow for the mach number distribution.
- the distance, not indicated on the drawing, by which the blade afflux edge 4 a in the tip region is shifted back compared with the conventional design in accordance with line a′ is larger than the distance, again not indicated, by which the blade afflux edge 4 a in the radius point U area is shifted forward relative to the conventional design in accordance with line a′.
- this may look different on account of the two-dimensional representation, whereas a rotor blade airfoil is obviously a three-dimensional shape.
- the sweep can also be designed such that the topmost airfoil section of a conventional rotor blade airfoil is retained. This will allow the blading in a previously existing case of an axial-flow turbomachine also to be renewed in a case with contoured walls, without having to adjust rub rings.
- the forward-back sweep of the present invention primarily reduces the local afflux mach number and so reduces shock losses. In the process, the forward-back sweep does not induce greater radial velocities that would be the cause of additional losses.
- a forward-back sweep also provides structural mechanical advantages, considering that the thrust, elastic axis and gravity centers will, when compared with the straight forward or back sweep, not change at all across blade span h until about 80% of the blade span, and only slightly from 80% blade span to the blade tip. Additional bending moments in the hub area, such as arising with straight forward or back sweep, are therefore avoided.
- the modified modes of vibration in the upper region of the airfoil 2 are above the second E.O., so that the arrangement of the present invention also causes no restrictions from the structural dynamic aspect. It is apparent that a plurality of especially design features other than those described herein may be incorporated in the present embodiment without departing from the inventive concept.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
Description
- This invention relates to a rotor blade airfoil of an axial-flow turbomachine, more particularly for a fan or a compressor high-pressure stage of a gas turbine system, having means in the tip area to improve supersonic performance. Associated state of the art is described in U.S. Pat. No. 3,989,406 and U.S. Pat. No. 4,012,172. The first-cited patent specification deals with the supersonic performance of rotor blade airfoils generally, while the second illustrates a forward swept airfoil, i.e. an airfoil on which the leading edge, starting from the blade root, first arches counter to the direction of flow, so that in a lateral view, the airfoil area or blade chord first continuously increases until, upon reaching a radius point, it arches in the direction of flow toward the blade tip area, where in said lateral view, the airfoil area or chord of the blade again decreases.
- The present invention also relates to the sweep of rotor blade airfoils, more particularly of the first compressor high-pressure stages or of a fan of gas turbines or aircraft gas turbine engines. Owing to the high peripheral speeds of said components and the practically zero-swirl inlet flow to the blade, supersonic regions occur in the blade tip area with mach numbers in excess of 1.4. These for several reasons negatively affect the performance of this component. Firstly, the efficiency decreases with increasing blade span, owing to growing shock losses, much more severely than with subsonic rotors. Also, the interaction of duct shock with blade tip swirl negatively affects the stability of the flow, because large blockage regions occur in that area whose nonlinear growth ultimately determines the stability limit of the compressor.
- In a broad aspect, the arrangement of the present invention provides means to remedy said problems.
- It is a particular object of the present invention to provide a solution to said problems by providing a forward-back-swept blade leading edge. Further objects and advantages of the present invention will become apparent from the subclaims.
- The invention is described more fully by means of a preferred embodiment in the light of a single drawing showing a rotor blade airfoil in greatly simplified lateral view.
-
Reference numeral 1 indicates the blade root andreference numeral 2 the airfoil of the rotor blade of an axial-flow turbomachine, more particularly for a fan or compressor high-pressure stage of a gas turbine system. Air is impinging onairfoil 2 in the direction of arrowhead 3 (=direction of flow 3) , i.e. the left-hand leading edge ofairfoil 2 is its afflux edge 4 a and the right-hand trailing edge is itsefflux edge 4 b. The axis of rotation of the rotor, omitted on the drawing, accordingly runs parallel to the direction of flow 3 and extends (far) below theblade root 1. - As usual,
airfoil 2 has a root region 2 a and atip region 2 b, the latter substantially extending along the outer 15% to 25%, more particularly along about 20% of the blade span h. The latter by amount is the difference (Ra−Ri), where Ra is the outer radius measured from the axis of rotation and Ri the inner radius of theairfoil 2. Shown in thetip region 2 b is both the afflux edge 4 a and theefflux edge 4 b of a conventionally designedairfoil 2, indicated by dashed lines a′ and b′. A conventionally shaped airfoil of this type, however, is impaired by the disadvantages cited above. - To remedy these disadvantages, the
airfoil 2 of the present invention is in thetip region 2 b provided with a forward-back sweep at least on the blade afflux edge 4 a as shown on the drawing, i.e. in thistip region 2 b the blade afflux edge 4 a extends, unlike in a conventional design, first counter to the direction of flow 3 and, upon reaching a radius point U, retreats in the direction of flow 3 in a manner more pronounced than with a conventionally designed blade afflux edge a′. For mechanical reasons, an angle α of a 90° order of magnitude is sought in the uppermost region, i.e. at the blade tip, between the afflux edge 4 a and the case contour indicated byline 5 of a case (omitted on the drawing) surrounding the rotor. - In the
tip region 2 b, theblade efflux edge 4 b has a shape essentially similar to that of the blade afflux edge 4 a, i.e. it reflects the forward-back sweep, as a comparison of thesolid line 4 b with the line b′ representing the conventional design will show. - In this arrangement, the back sweep can be made more pronounced than the forward sweep, so as to allow for the mach number distribution. This means that the distance, not indicated on the drawing, by which the blade afflux edge4 a in the tip region is shifted back compared with the conventional design in accordance with line a′, is larger than the distance, again not indicated, by which the blade afflux edge 4 a in the radius point U area is shifted forward relative to the conventional design in accordance with line a′. On the drawing, this may look different on account of the two-dimensional representation, whereas a rotor blade airfoil is obviously a three-dimensional shape.
- The sweep can also be designed such that the topmost airfoil section of a conventional rotor blade airfoil is retained. This will allow the blading in a previously existing case of an axial-flow turbomachine also to be renewed in a case with contoured walls, without having to adjust rub rings.
- The forward-back sweep of the present invention primarily reduces the local afflux mach number and so reduces shock losses. In the process, the forward-back sweep does not induce greater radial velocities that would be the cause of additional losses.
- A forward-back sweep also provides structural mechanical advantages, considering that the thrust, elastic axis and gravity centers will, when compared with the straight forward or back sweep, not change at all across blade span h until about 80% of the blade span, and only slightly from 80% blade span to the blade tip. Additional bending moments in the hub area, such as arising with straight forward or back sweep, are therefore avoided. The modified modes of vibration in the upper region of the
airfoil 2 are above the second E.O., so that the arrangement of the present invention also causes no restrictions from the structural dynamic aspect. It is apparent that a plurality of especially design features other than those described herein may be incorporated in the present embodiment without departing from the inventive concept. -
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- Ra Outer radius of 2
- Ri Inner radius of 2
- W Radius point
- a′ Conventional contour of4 a in 2 b
- b′ Conventional contour of4 b in 2 b
- h Blade span
- α Angle between4 a and 5
Claims (3)
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19812624 | 1998-03-23 | ||
DE19812624.7 | 1998-03-23 | ||
DE19812624A DE19812624A1 (en) | 1998-03-23 | 1998-03-23 | Rotor blade of an axial flow machine |
PCT/EP1999/001981 WO1999049185A1 (en) | 1998-03-23 | 1999-03-23 | Rotor blade of an axial-flow engine |
Publications (2)
Publication Number | Publication Date |
---|---|
US20010014285A1 true US20010014285A1 (en) | 2001-08-16 |
US6358003B2 US6358003B2 (en) | 2002-03-19 |
Family
ID=7861930
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/424,481 Expired - Lifetime US6358003B2 (en) | 1998-03-23 | 1999-03-23 | Rotor blade an axial-flow engine |
Country Status (4)
Country | Link |
---|---|
US (1) | US6358003B2 (en) |
EP (1) | EP0990090B1 (en) |
DE (2) | DE19812624A1 (en) |
WO (1) | WO1999049185A1 (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2969230A1 (en) * | 2010-12-15 | 2012-06-22 | Snecma | COMPRESSOR BLADE WITH IMPROVED STACKING LAW |
CN103946110A (en) * | 2011-09-29 | 2014-07-23 | 斯奈克玛 | Blade for a fan of a turbomachine, notably of the unducted fan type, corresponding fan and corresponding turbomachine |
CN104583604A (en) * | 2012-07-12 | 2015-04-29 | 斯奈克玛 | Turbomachine vane having an airfoil designed to provide improved aerodynamic and mechanical properties |
CN105332948A (en) * | 2015-10-23 | 2016-02-17 | 上海交通大学 | Improved compressor blade and achieving method thereof |
US9695695B2 (en) | 2012-01-30 | 2017-07-04 | Snecma | Turbojet fan blade |
CN107023513A (en) * | 2017-06-16 | 2017-08-08 | 广东美的制冷设备有限公司 | Axial-flow windwheel and air conditioner |
CN113167122A (en) * | 2018-12-12 | 2021-07-23 | 索拉透平公司 | Modal response tuned turbine blade |
Families Citing this family (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CA2426892C (en) | 2002-08-16 | 2011-10-25 | The Fuel Genie Corporation | Device and method for changing angular velocity of airflow |
ES2465090T3 (en) * | 2002-12-20 | 2014-06-05 | Smith & Nephew, Inc. | High performance knee prostheses |
FR2851798B1 (en) * | 2003-02-27 | 2005-04-29 | Snecma Moteurs | TURBOREACTOR TURBINE BOW |
US7055306B2 (en) | 2003-04-30 | 2006-06-06 | Hamilton Sundstrand Corporation | Combined stage single shaft turbofan engine |
TWI256444B (en) * | 2004-05-06 | 2006-06-11 | Sunonwealth Electr Mach Ind Co | Air outlet structure for an axial-flow fan |
DE502004010281D1 (en) * | 2004-06-02 | 2009-12-03 | Rolls Royce Deutschland | Compressor blade, especially for the fan of aircraft engines |
CN101044213B (en) * | 2004-10-12 | 2014-04-02 | 卢米尼克斯股份有限公司 | Methods for forming dyed microspheres and populations of dyed microspheres |
JP4863162B2 (en) * | 2006-05-26 | 2012-01-25 | 株式会社Ihi | Fan blade of turbofan engine |
DE102006026968A1 (en) | 2006-06-09 | 2008-01-24 | Rolls-Royce Deutschland Ltd & Co Kg | Turbomachine with rotors of high specific energy output |
JP4911344B2 (en) * | 2006-07-04 | 2012-04-04 | 株式会社Ihi | Turbofan engine |
GB0701866D0 (en) | 2007-01-31 | 2007-03-14 | Rolls Royce Plc | Tone noise reduction in turbomachines |
US20100303604A1 (en) * | 2009-05-27 | 2010-12-02 | Dresser-Rand Company | System and method to reduce acoustic signature using profiled stage design |
US8668446B2 (en) | 2010-08-31 | 2014-03-11 | General Electric Company | Supersonic compressor rotor and method of assembling same |
US9022730B2 (en) | 2010-10-08 | 2015-05-05 | General Electric Company | Supersonic compressor startup support system |
US8864454B2 (en) | 2010-10-28 | 2014-10-21 | General Electric Company | System and method of assembling a supersonic compressor system including a supersonic compressor rotor and a compressor assembly |
US8657571B2 (en) | 2010-12-21 | 2014-02-25 | General Electric Company | Supersonic compressor rotor and methods for assembling same |
US8827640B2 (en) | 2011-03-01 | 2014-09-09 | General Electric Company | System and methods of assembling a supersonic compressor rotor including a radial flow channel |
US8770929B2 (en) | 2011-05-27 | 2014-07-08 | General Electric Company | Supersonic compressor rotor and method of compressing a fluid |
US8550770B2 (en) | 2011-05-27 | 2013-10-08 | General Electric Company | Supersonic compressor startup support system |
US9102397B2 (en) * | 2011-12-20 | 2015-08-11 | General Electric Company | Airfoils including tip profile for noise reduction and method for fabricating same |
FR2999151B1 (en) * | 2012-12-07 | 2017-01-27 | Snecma | PROPELLER BLADE FOR TURBOMACHINE |
FR3021706B1 (en) * | 2014-05-28 | 2020-05-15 | Safran Aircraft Engines | AIRCRAFT TURBOPROPELLER COMPRISING TWO COAXIAL PROPELLERS. |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
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US3467197A (en) * | 1968-05-07 | 1969-09-16 | Bell Aerospace Corp | Rotor blade |
US3989406A (en) | 1974-11-26 | 1976-11-02 | Bolt Beranek And Newman, Inc. | Method of and apparatus for preventing leading edge shocks and shock-related noise in transonic and supersonic rotor blades and the like |
US4012172A (en) * | 1975-09-10 | 1977-03-15 | Avco Corporation | Low noise blades for axial flow compressors |
GB2164098B (en) * | 1984-09-07 | 1988-12-07 | Rolls Royce | Improvements in or relating to aerofoil section members for turbine engines |
JP3697296B2 (en) | 1995-08-25 | 2005-09-21 | 株式会社東芝 | Turbine blade |
US5642985A (en) * | 1995-11-17 | 1997-07-01 | United Technologies Corporation | Swept turbomachinery blade |
-
1998
- 1998-03-23 DE DE19812624A patent/DE19812624A1/en not_active Withdrawn
-
1999
- 1999-03-23 WO PCT/EP1999/001981 patent/WO1999049185A1/en active IP Right Grant
- 1999-03-23 DE DE59907613T patent/DE59907613D1/en not_active Expired - Fee Related
- 1999-03-23 US US09/424,481 patent/US6358003B2/en not_active Expired - Lifetime
- 1999-03-23 EP EP99916878A patent/EP0990090B1/en not_active Expired - Lifetime
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2969230A1 (en) * | 2010-12-15 | 2012-06-22 | Snecma | COMPRESSOR BLADE WITH IMPROVED STACKING LAW |
EP2652336B1 (en) * | 2010-12-15 | 2019-05-01 | Safran Aircraft Engines | Turbomachine blade with improved stacking line |
CN103946110A (en) * | 2011-09-29 | 2014-07-23 | 斯奈克玛 | Blade for a fan of a turbomachine, notably of the unducted fan type, corresponding fan and corresponding turbomachine |
JP2015501247A (en) * | 2011-09-29 | 2015-01-15 | スネクマ | Especially for ducted fan turbomachine fan blades, corresponding fans, and corresponding turbomachines |
RU2606787C2 (en) * | 2011-09-29 | 2017-01-10 | Снекма | Turbine machine propeller blade, particularly fan without fairing, and corresponding propeller and turbo machine |
US9630704B2 (en) | 2011-09-29 | 2017-04-25 | Snecma | Blade for a fan of a turbomachine, notably of the unducted fan type, corresponding fan and corresponding turbomachine |
US9695695B2 (en) | 2012-01-30 | 2017-07-04 | Snecma | Turbojet fan blade |
CN104583604A (en) * | 2012-07-12 | 2015-04-29 | 斯奈克玛 | Turbomachine vane having an airfoil designed to provide improved aerodynamic and mechanical properties |
CN105332948A (en) * | 2015-10-23 | 2016-02-17 | 上海交通大学 | Improved compressor blade and achieving method thereof |
CN107023513A (en) * | 2017-06-16 | 2017-08-08 | 广东美的制冷设备有限公司 | Axial-flow windwheel and air conditioner |
CN113167122A (en) * | 2018-12-12 | 2021-07-23 | 索拉透平公司 | Modal response tuned turbine blade |
Also Published As
Publication number | Publication date |
---|---|
DE59907613D1 (en) | 2003-12-11 |
WO1999049185A1 (en) | 1999-09-30 |
EP0990090A1 (en) | 2000-04-05 |
DE19812624A1 (en) | 1999-09-30 |
US6358003B2 (en) | 2002-03-19 |
EP0990090B1 (en) | 2003-11-05 |
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