CN101169137A - Asymmetric compressor air extraction method - Google Patents
Asymmetric compressor air extraction method Download PDFInfo
- Publication number
- CN101169137A CN101169137A CNA2007101817876A CN200710181787A CN101169137A CN 101169137 A CN101169137 A CN 101169137A CN A2007101817876 A CNA2007101817876 A CN A2007101817876A CN 200710181787 A CN200710181787 A CN 200710181787A CN 101169137 A CN101169137 A CN 101169137A
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- CN
- China
- Prior art keywords
- compressor
- extraction
- housing
- stall
- notch
- 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.)
- Pending
Links
- 238000000605 extraction Methods 0.000 title claims description 15
- 238000000034 method Methods 0.000 claims abstract description 21
- 239000000284 extract Substances 0.000 claims description 3
- 230000002452 interceptive effect Effects 0.000 claims description 3
- 230000002093 peripheral effect Effects 0.000 claims description 3
- 238000012797 qualification Methods 0.000 claims 1
- 230000015572 biosynthetic process Effects 0.000 abstract description 7
- 230000005284 excitation Effects 0.000 abstract description 5
- 230000001427 coherent effect Effects 0.000 abstract 2
- 230000000740 bleeding effect Effects 0.000 description 13
- 238000000465 moulding Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000005086 pumping Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- 238000010248 power generation Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000012857 repacking Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
- F02C6/00—Plural gas-turbine plants; Combinations of gas-turbine plants with other apparatus; Adaptations of gas-turbine plants for special use
- F02C6/04—Gas-turbine plants providing heated or pressurised working fluid for other apparatus, e.g. without mechanical power output
- F02C6/06—Gas-turbine plants providing heated or pressurised working fluid for other apparatus, e.g. without mechanical power output providing compressed gas
- F02C6/08—Gas-turbine plants providing heated or pressurised working fluid for other apparatus, e.g. without mechanical power output providing compressed gas the gas being bled from the gas-turbine compressor
-
- 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
- F04D29/40—Casings; Connections of working fluid
- F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
- F04D29/44—Fluid-guiding means, e.g. diffusers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/02—Surge control
- F04D27/0207—Surge control by bleeding, bypassing or recycling fluids
- F04D27/0215—Arrangements therefor, e.g. bleed or by-pass valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/02—Surge control
- F04D27/0207—Surge control by bleeding, bypassing or recycling fluids
- F04D27/0223—Control schemes therefor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/02—Surge control
- F04D27/0207—Surge control by bleeding, bypassing or recycling fluids
- F04D27/023—Details or means for fluid extraction
-
- 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
- F04D29/40—Casings; Connections of working fluid
-
- 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
- F04D29/40—Casings; Connections of working fluid
- F04D29/52—Casings; Connections of working fluid for axial pumps
- F04D29/54—Fluid-guiding means, e.g. diffusers
- F04D29/541—Specially adapted for elastic fluid pumps
- F04D29/545—Ducts
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The present invention relates to an anisomerous compressor suction method. The present invention provides a method to mistune rotating stall aerodynamics by preventing the formation of coherent unsteady loads. Compressor air is extracted in an asymmetric circumferential pattern. The asymmetric bleed pattern disrupts the rotating stall cell (10) rotational pattern, preventing the formation of a coherent aerodynamic excitation.
Description
Technical field
The present invention relates to asymmetric compressor air extraction method.
Background technique
Thereby the parallel-flow turbine engine that is used for power generation industries is designed to fixing rotating speed and the operation of output optimization ground.In addition, traditional axial flow industrial gas turbines compressor has the level of limited geometry-variable and the effect (air extraction) of bleeding.These three factors, i.e. the geometrical shape and limited the bleeding of the operation of fixed speed, limited variable level make to produce the aerodynamic force state that exceeds scope of design significantly in the running starting and shut down.Stall (stall) will appear rotating in these exceed the running of scope of design in Axial Flow Compressor.
Rotate the partial stall unit that occurs when stall itself shows as only about half of rotating speed rotation with wheel speed.These unit have produced the intrinsic unsettled aerodynamics load that acts on rotor blade and stator vane.When the rapid change of rotor, the stall element number changes, and sets different nodal diameter (nodal diameter) thus.The oscillating action for rotor blade and stator vane that is caused by the aerodynamics load that rotates stall may make and damage and the susceptibility of the fault that takes place too early increases for normal blade.
Summary of the invention
The present invention is by elimination or reduce the intrinsic aerodynamic force educational level that is produced by rotation stall, thereby has improved the reliability of Axial Flow Compressor rotor and stator vane.More particularly, the invention provides the method for a kind of feasible rotation stall aerodynamics off resonance, prevent the formation of intrinsic unsteady load thus.
The present invention can be combined in and a kind ofly implement in the method for control air-flow in compressor, and this method comprises: partial velocity or the operation that exceeds scope of design produce flow interfering; Spaced positions place, a series of circumferential asymmetric ground in the selected axial part office of compressor extracts air-flow, and generation is bled pattern so that react on flow interfering thus.
The present invention can be combined in and another kind of implement in the method for control air-flow in compressor, and this method comprises: the extraction of compressor air is activated around the peripheral of the housing of this compressor, so that react on the interference of for example rotating stall asymmetricly.
Description of drawings
With reference to the following description of preferred embodiment and in conjunction with the accompanying drawings, the present invention may be better understood, in the accompanying drawings:
Fig. 1 is the schematic representation that rotates stall;
Fig. 2 is the schematic representation according to the asymmetric compression extraction air of embodiments of the invention; With
Fig. 3 is the schematic perspective view according to the compressor that is suitable for asymmetric compression extraction air of embodiments of the invention.
Embodiment
Thereby the parallel-flow turbine engine that is used for power generation industries is designed to fixing rotating speed and the operation of output optimization ground.In addition, traditional axial flow industrial gas turbines compressor has the level of limited geometry-variable and the effect of bleeding.These three factors, i.e. the geometrical shape and limited the bleeding of the operation of fixed speed, limited variable level make to produce the aerodynamic force state that exceeds scope of design significantly in the running starting and shut down.Stall will appear rotating in these exceed the running of scope of design in Axial Flow Compressor.
As Fig. 1 schematically shown in, rotate the partial stall unit 10 (ω that occur when stall itself shows as only about half of rotating speed rotation with wheel speed
Stall cells≈ 1/2 ω
Engine).These unit have produced the intrinsic unsettled aerodynamics load that acts on rotor blade and stator vane 12.When the rapid change of rotor, the stall element number changes, and sets the different incentive characteristics that is called the node diameter thus.The oscillating action for rotor blade and stator vane that is caused by the aerodynamics load that rotates stall may make and damage and the susceptibility of the fault that takes place too early increases for normal blade.
By eliminating or reducing, can obtain improved Axial Flow Compressor blade reliability by rotating the intrinsic aerodynamic forces that stall produces.The reduction of these aerodynamics vibrational loadings makes the damage tolerance of blade increase to the damage tolerance of normal operation, for example end fray, burn into and the damage of leading edge foreign objects.
The present invention encourages (aerodynamic excitation) by the aerodynamics of eliminating or reduce by rotation stall generation that acts on Axial Flow Compressor rotor and stator vane, thereby has improved the reliability of Axial Flow Compressor rotor and stator vane.More particularly, thus the invention provides a kind of formation by preventing intrinsic unsteady load makes the method for rotating the off resonance of stall aerodynamics.
Therefore, more particularly, the present invention proposes a kind of for example new method of the interference of compressor rotation stall of eliminating or reduce, for example be in one or more selected axial positions (level) compressor air in a series of circumferential spaced positions discharges optionally asymmetricly, its mode of circumferentially selecting depends on the starting point (origin of the variations) of variation, so that react on the flow disturbance that rotates stall.In this case, pumping process can begin, and that is to say that the stall conditions that the rotation stall conditions maybe may occur can stop by asymmetric extracting air.Because this is discernible phenomenon-part rotating speed and/or sub load in a kind of running, therefore without any need for sensor.
In an embodiment of the present invention, as Fig. 2 and 3 schematically shown in, by footpath outside the flow hole or the notch of a series of roughly moulding that is circumferential asymmetric pattern on the path wall 18, extract compressor air.This pattern of bleeding is determined as the function of the aerodynamics intensity of rotating stall nodal diameter pattern and unit.This asymmetric multistage exhaust mode has disturbed and has rotated the rotary mode of stall unit, thereby prevents the formation of intrinsic aerodynamics excitation.
Fig. 3 schematically shows according to the bleeder hole that is provided with roughly moulding of embodiments of the invention or the Axial Flow Compressor of notch.Roughly the bleeder hole of moulding or notch 16 are defined as and are convenient to make compressor air optionally to pass the compressor housing discharge.Inlet is thought with box lunch and is moved the air that is extracted when must or need and guide this air again by correcting through (unshowned) pipeline of QA (unshowned) stop valve accordingly.If similar bleeder hole is arranged on many axial stations (station) and locates, circumferentially corresponding pump-line is at the shared same control valve of two or more stations.If circumferentially the bleeder hole or the notch of series activated simultaneously with common order, circumferentially the pump-line of series can be connected to shared control valve.In order to save bleeding of high-pressure air, in case the stall unit is suppressed, control unit can be closed this valve.In one embodiment, bleed and continue a preset time section and finish subsequently.In another embodiment, bleed and after it starts, reduce gradually.Also can adopt other the rules of bleeding according to required or desirable requirement.
As mentioned above, for formation and the off resonance of feasible thus rotation stall aerodynamics that prevents intrinsic unsteady load, the invention provides a kind of like this assembly, wherein compressor air is extracted via the hole or the notch 16 that are a series of roughly moulding of circumferential asymmetric pattern on the path wall 18 that directly flows outside, shown in Fig. 2 signal.Thereby this pattern of bleeding can be used as the function of the aerodynamics intensity of rotating stall nodal diameter pattern and unit to be determined based on experiment and analysis.These are bled and can be positioned at single axial position or be positioned at a plurality of axial positions, and this depends on the characteristic of rotating stall, required pumping airflow and the restriction of motor configuration.As can be seen from Figure 3, this embodiment expresses the asymmetric structure of bleeding with two axial positions.The quantity of axial position, circumferential arc length, bleeder hole shape and quantity are determined based on the characteristic of rotating stall.This asymmetric multistage exhaust mode has disturbed and has rotated the rotary mode of stall unit, thereby prevents the formation of intrinsic aerodynamics excitation.
Be appreciated that from the above description asymmetric exhaust feature comprises: be positioned at the asymmetric isolated bleeding point 16 at each specific axial position 20 place on compressor housing 18, it is positioned at the specific arc length θ at specific circumferential position place
ArcScope is interior and have the limited shape of bleeding, so that required total pumping airflow is provided.In one embodiment, θ
ArcBe about 90 degree.
The application of corresponding separated type housing, on bleeding point 16 superposed half housings, the maneuverability that provides easier on-the-spot repacking and improved entering (unshowned) to bleed collector and pipeline thus.Be appreciated that from the above description multistage bleeding need bleed collector so that steering flow leaves this unit.
Therefore, the invention provides following beneficial technical effects: 1) eliminate/reduce intrinsic unstable air dynamics excitation for blade; 2) can be to having the existing motor of separated type shell construction; 3) can improve the aerodynamics blade; 4) pass through to increase the damage tolerance of end fray, corrosion pit and leading edge damage, thereby improved the reliability of compressor blade.
Although the present invention is considered to the most practical and most preferred embodiment and is described with reference to current, but be to be understood that and the invention is not restricted to disclosed embodiment, opposite is, the present invention is intended to cover different modification and equivalent configurations, and these all are included in the spirit and scope that limited by appended claim.
Components list
10 partial stall unit
12 blades
16 aspirating holes or notch
18 compressor housings/wall
20 axial positions
Claims (10)
- One kind in compressor control air-flow method, it comprises:From near or the downstream of selected axial component (20), via the housing (18) of this compressor with circumferential asymmetric pattern extraction (16) high-pressure air, so that react on the flow interfering of for example rotating stall.
- 2. the method for claim 1 is characterized in that, the extraction of described high-pressure air is via peripheral a plurality of holes that are provided with or notch (16) around this compressor (18) asymmetricly.
- 3. the method for claim 1 is characterized in that, described housing is the separated type housing, and the extraction of described high-pressure air is via a plurality of holes or the notch that are provided with on the upper casing part of described separated type housing.
- 4. the method for claim 1 is characterized in that, comprises via the circular arc θ that is arranged on the characteristic qualification that forms by required flow and rotation stall ArcInterior a plurality of holes or notch extract high-pressure air.
- 5. the method for claim 1 is characterized in that, described a plurality of holes or notch (16) are provided with described circular arc θ asymmetricly AreIn.
- 6. the method for claim 1 is characterized in that, described extraction finishes after a predetermined amount of time.
- 7. the method for claim 1 is characterized in that, described extraction little by little reduces after it starts.
- One kind in compressor control air-flow method, it comprises:The extraction of compressor air is activated around the peripheral of the housing (18) of this compressor, so that react on the interference of for example rotating stall asymmetricly.
- 9. method as claimed in claim 8 is characterized in that, the extraction of described high-pressure air is arranged on circular arc θ via the periphery of the housing (18) that centers on this compressor ArcInterior a plurality of holes or notch (16), this circular arc limits by the characteristic that required flow and rotation stall form.
- 10. method as claimed in claim 8 is characterized in that, described housing is the separated type housing, and the extraction of described high-pressure air is via a plurality of holes or the notch that are provided with on the upper casing part of described separated type housing.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US11/588,389 US20080101922A1 (en) | 2006-10-27 | 2006-10-27 | Asymmetric compressor air extraction method |
| US11/588389 | 2006-10-27 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101169137A true CN101169137A (en) | 2008-04-30 |
Family
ID=39244627
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2007101817876A Pending CN101169137A (en) | 2006-10-27 | 2007-10-29 | Asymmetric compressor air extraction method |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US20080101922A1 (en) |
| JP (1) | JP2008111435A (en) |
| KR (1) | KR20080038041A (en) |
| CN (1) | CN101169137A (en) |
| DE (1) | DE102007051633A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105378294A (en) * | 2013-10-17 | 2016-03-02 | 三菱重工业株式会社 | Compressor and gas turbine |
| CN109083847A (en) * | 2017-06-13 | 2018-12-25 | 通用电气公司 | Compressor bleed air equipment and its bleed method for turbogenerator |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110274537A1 (en) * | 2010-05-09 | 2011-11-10 | Loc Quang Duong | Blade excitation reduction method and arrangement |
| KR20120077335A (en) | 2010-12-30 | 2012-07-10 | 한국항공우주연구원 | Axial compressor and method to stabilize fluid thereof |
| EP2900940A4 (en) * | 2012-09-28 | 2016-07-20 | United Technologies Corp | Case assembly for a gas turbine engine |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4196472A (en) * | 1977-09-09 | 1980-04-01 | Calspan Corporation | Stall control apparatus for axial flow compressors |
| US5340271A (en) * | 1990-08-18 | 1994-08-23 | Rolls-Royce Plc | Flow control method and means |
| US5462403A (en) * | 1994-03-21 | 1995-10-31 | United Technologies Corporation | Compressor stator vane assembly |
| US5984625A (en) * | 1996-10-15 | 1999-11-16 | California Institute Of Technology | Actuator bandwidth and rate limit reduction for control of compressor rotating stall |
| US6098010A (en) * | 1997-11-20 | 2000-08-01 | The Regents Of The University Of California | Method and apparatus for predicting and stabilizing compressor stall |
| US6409469B1 (en) * | 2000-11-21 | 2002-06-25 | Pratt & Whitney Canada Corp. | Fan-stator interaction tone reduction |
| US6506010B1 (en) * | 2001-04-17 | 2003-01-14 | General Electric Company | Method and apparatus for compressor control and operation in industrial gas turbines using stall precursors |
-
2006
- 2006-10-27 US US11/588,389 patent/US20080101922A1/en not_active Abandoned
-
2007
- 2007-10-25 KR KR1020070107902A patent/KR20080038041A/en not_active Application Discontinuation
- 2007-10-25 JP JP2007277085A patent/JP2008111435A/en not_active Withdrawn
- 2007-10-26 DE DE102007051633A patent/DE102007051633A1/en not_active Withdrawn
- 2007-10-29 CN CNA2007101817876A patent/CN101169137A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105378294A (en) * | 2013-10-17 | 2016-03-02 | 三菱重工业株式会社 | Compressor and gas turbine |
| CN105378294B (en) * | 2013-10-17 | 2017-07-25 | 三菱重工业株式会社 | Compressor and gas turbine |
| CN109083847A (en) * | 2017-06-13 | 2018-12-25 | 通用电气公司 | Compressor bleed air equipment and its bleed method for turbogenerator |
| US11635030B2 (en) | 2017-06-13 | 2023-04-25 | General Electric Company | Compressor bleed apparatus for a turbine engine |
Also Published As
| Publication number | Publication date |
|---|---|
| KR20080038041A (en) | 2008-05-02 |
| DE102007051633A1 (en) | 2008-04-30 |
| US20080101922A1 (en) | 2008-05-01 |
| JP2008111435A (en) | 2008-05-15 |
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| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
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| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Open date: 20080430 |