CN101012837A - Centrifugal compressor having air removal jet box structure - Google Patents
Centrifugal compressor having air removal jet box structure Download PDFInfo
- Publication number
- CN101012837A CN101012837A CN 200710063502 CN200710063502A CN101012837A CN 101012837 A CN101012837 A CN 101012837A CN 200710063502 CN200710063502 CN 200710063502 CN 200710063502 A CN200710063502 A CN 200710063502A CN 101012837 A CN101012837 A CN 101012837A
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- China
- Prior art keywords
- bleed
- channel
- passage
- guide channel
- centrifugal compressor
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- 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.)
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- 230000000740 bleeding effect Effects 0.000 claims description 6
- 230000015572 biosynthetic process Effects 0.000 claims description 2
- 238000000926 separation method Methods 0.000 abstract description 15
- 238000002347 injection Methods 0.000 abstract description 7
- 239000007924 injection Substances 0.000 abstract description 7
- 238000010276 construction Methods 0.000 abstract 1
- 230000004907 flux Effects 0.000 abstract 1
- 238000001179 sorption measurement Methods 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 25
- 238000000034 method Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 241001012508 Carpiodes cyprinus Species 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000013467 fragmentation Methods 0.000 description 1
- 238000006062 fragmentation reaction Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
Images
Classifications
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- 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
- F04D29/4206—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for elastic fluid pumps
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- 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
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/68—Combating cavitation, whirls, noise, vibration or the like; Balancing by influencing boundary layers
- F04D29/681—Combating cavitation, whirls, noise, vibration or the like; Balancing by influencing boundary layers especially adapted for elastic fluid pumps
- F04D29/685—Inducing localised fluid recirculation in the stator-rotor interface
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
A centrifugal compressor with an air-bleed and a jetting box construction belongs to the turbo-machine field. The invention is characterized in that the wall of the box of worm frame is arranged with at least three exhaust-injection guide channels uniformly arranged around the rotary axle of compressor, while it contains exhaust channels and injection channels. The opening of the exhaust channels is arranged at the wall at the inlet of the non-blade expander channel, and vertical to the wall of inlet box. The opening of the injection channel is at the most torsion of the channel formed by the worm frame and blade, while it is at same direction of main absolute speed of most torsion. The exhaust channel and the injection channel are connected via the guide channel. The inventive exhaust-injection guide channel can exhaust the adhere layer at the wall of expander, restrain the flow separation of expander, and fill high-energy injection into the channel of blade wheel, to restrain the flow separation of adsorption face and restrain the flow separation at small flux, to improve the speed-lost allowance and efficiency.
Description
Technical field:
Have the centrifugal compressor of bleeding and belong to impeller machinery technical field, relate to the improvement of turbomachine casings such as automobile-used, peculiar to vessel pressurized machine centrifugal compressor, industrial centrifugal compressor and aviation centrifugal compressor with the jet case structure.
Technical background:
Impeller type gas compressors such as centrifugal-flow compressor have advantages such as efficient height, volume weight is light, running is steady, but its operating mode are limited in scope with respect to reciprocating compressor.Under the centrifugal-flow compressor low discharge operating mode will phenomenons such as large scale flow separation appear at impeller and Diffuser, the unstable operation phenomenon occurs, cause stall even surge, directly cause compressor efficiency and pressure ratio sharply to descend, the life-span seriously shortens, even directly damages in the short time.
Existing centrifugal compressor blade and Diffuser shape are determined according to the design point operating mode, obtain than the dominance energy at design point.Under design discharge, impeller does work to gas, does not have large scale flow separation phenomenon at blade surface and takes place; In the gas energy of impeller outlet, the kinetic energy of major part is arranged, Diffuser is converted into static energy with kinetic energy, does not also have the flow separation phenomenon under design discharge.But under the low discharge operating mode, the increase of the blade air-flow angle of attack thickens impeller blade suction surface boundary layer, large scale flow separation phenomenon further takes place under the effect of adverse pressure gradient, has the whirlpool than large scale to generate, develop and fragmentation, and is accompanied by bigger flow losses; Separate more seriously when flow further reduces, will cause gas compressor the unstable operation phenomenon to occur, cause stall even surge.During small flow, the inherent casing wall of Diffuser has large scale flow separation phenomenon to take place equally, can cause stall phenomenon and flow losses to increase, even surge.In order to improve compressor efficiency, need to suppress the flow separation of impeller blade suction surface and Diffuser section casing wall.
Summary of the invention:
The object of the invention is, overcome the defective of prior art, a kind of centrifugal compressor of bleeding with the jet case structure that has has been proposed, opened at the casing wall of this centrifugal compressor and to have bled-the jet guide channel, extract shallow bid high-energy fluid from the casing wall that is positioned at the diffuser inlet, through the aperture injection impeller channel of small aperture passage, can play and draw the Diffuser boundary layer and strengthen the double effects that impeller passage flows from the casing wall at impeller place.
The present invention contains gas compressor rotating shaft (1), impeller (3), blade (4), impeller back of the body dish (6) and volute (7), described impeller back of the body dish (6) forms vaneless diffuser passage (8) with volute (7), it is characterized in that, having at least 3 on the casing wall of volute (7) is circumferentially uniform bleeding of center-jet guide channel (9) with gas compressor rotating shaft (1), described bleeding-jet guide channel (9) contains bleed-off passage (10) and fluidic channel (14), described bleed-off passage (10) is opened on the casing wall place of vaneless diffuser passage (8) inlet, and this bleed-off passage (10) is perpendicular to this inlet casing wall, described fluidic channel (14) is opened on described volute (7) and twists curvature with the maximum of the runner of blade (4) formation, and the direction of described fluidic channel (14) is identical with the main flow absolute velocity direction at this maximum curvature place; Connect by guide channel (12) between described bleed-off passage (10) and the fluidic channel (14).
The joint of described bleed-off passage (10) and guide channel (12) forms the spherical air chamber (11) of bleed-off passage.
The joint of described fluidic channel (14) and guide channel (12) forms the spherical air chamber (13) of fluidic channel.
The aperture of described bleed-off passage (10), guide channel (12) and fluidic channel (14) is 1~2mm.
The diameter of spherical air chamber (11) of described bleed-off passage and the spherical air chamber of fluidic channel (13) is 3~4mm.
Evidence, proposed by the invention having are bled and the centrifugal compressor of jet case structure, bleed-effect of jet guide channel by it, can take out the boundary layer of Diffuser section casing wall, suppress the flow separation of diffuser; And in impeller channel, inject high-octane jet, and use the method for the excitation of flowing to suppress impeller blade suction surface flow separation, finally suppress the flow separation under the small flow situation, improve centrifugal compressor stall margin and efficient.
Description of drawings:
Fig. 1 is an overall cross-sectional schematic of the present invention.
Fig. 2 bleeds-jet guide channel cross-sectional schematic.
Fig. 3 is the sectional view along guide channel 12.
Fig. 4 is a jet runner circumferential direction angle schematic representation.
Embodiment
Accompanying drawings the specific embodiment of the present invention.
As shown in Figure 1, gas compressor rotating shaft 1, impeller fixing bolt 2, impeller 3 has blade 4 on the impeller 3, sealing block 5, impeller back of the body dish 6, volute 7 is existing gas compressor universal component, and vaneless diffuser passage 8 is combined to form by impeller back of the body dish 6 and volute 7.The inlet air flow direction is B, and compressor impeller 4 sense of rotation are C.The present invention is characterised in that, on the casing wall of volute 7, have and be no less than 3 bleed-jet guide channel 9, each bar bleeds-and jet guide channel 9 is that the center is circumferentially uniform with gas compressor rotating shaft 1, this guide channel rear end suction port is opened on the casing wall place of vaneless diffuser 8 inlets, the front end jet hole is opened on the maximum distortion curvature of the runner that forms between the blade 4, gas enters from the rear end suction port, is sprayed by the front end jet hole through guide channel.
Bleed as shown in Figure 2 ,-jet guide channel 9 is made up of bleed-off passage 10, guide channel 12 and fluidic channel 14.For reducing air-flow in the loss of turning point of flowing, the joint of bleed-off passage 10 and guide channel 12, globulate is done in the joint of fluidic channel 14 and guide channel 12, is respectively spherical air chamber 11 of bleed-off passage and the spherical air chamber 13 of fluidic channel.
Be to enlarge compressor stall nargin, improve compressor efficiency, bleed-following condition can be satisfied in the size and the position of jet guide channel 9 each several parts.The diameter of bleed-off passage 10, guide channel 12 and fluidic channel 14 is 1~2mm, concrete diameter determine by bleed-the bar number and the gas compressor flow of jet guide channel 9 decide, make via bleed-gas flow that jet guide channel 9 is taken away is about 1%~2% of gas compressor working flow, is good with 1~2mm generally.The diameter of spherical air chamber 11 of bleed-off passage and the spherical air chamber 13 of fluidic channel is 3~4mm.
Bleed-off passage 10 is perpendicular to Diffuser 8 inlet casing walls.On section shown in Figure 2, fluidic channel 14 and inlet air flow direction B become angle a in the other direction, are about 20 °~30 °; Fluidic channel 14 is b (as shown in Figure 3) with the angle of impeller sense of rotation C; As shown in Figure 4, fluidic channel 14 its jet directions should be consistent with blade path maximum curvature place main flow absolute velocity c direction, promptly with respect to the absolute velocity direction of static wall, this absolute velocity c for respect to the impeller of rotation in the main flow relative velocity w of blade path maximum curvature place and impeller the two the aggregate velocity of velocity of moving space u that rotates in a circumferential direction at this place.
Bleed-jet guide channel 9 finishes with volute 7 casting in the centrifugal compressor manufacture process.
In the centrifugal compressor working procedure, direction along gas flow, pressure raises gradually, be that gas pressure is higher than gas in the aperture of fluidic channel 14 on wall in the aperture of bleed-off passage 10 on wall, owing to bleed-jet guide channel 9 diameters are much smaller than blade path, have a small gangs of gas from the gas compressor rear portion via bleed-jet guide channel 9 injects anterior leaflet passage maximum curvatures, accounts for 1~2% of total gas couette.Because bleed position is the ingress of vaneless diffuser passage 8, the gas of extraction is to cause the boundary layer that gas flow is separated in the vaneless diffuser passage 8 just, helps to reduce loss, improves diffuser efficient, enlarges stall margin; And be gas from the rear portion extraction via the gas that fluidic channel penetrates, its pressure height, be high energy gases, the mobile of anterior leaflet passage maximum curvature place that the easiest generation is separated is an excitation, can effectively blow away the boundary layer that blade suction surface constantly thickens, suppress its separation, reduce separation losses, enlarge compressor stall nargin.
The present invention utilize this bleed-jet guide channel 9 realized extracting the boundary layer, diffuser inlet simultaneously and added the blade path high-energy and encouraged the dual income that suppresses the centrifugal compressor flow separation, can effectively enlarge the stall margin of gas compressor, improve compressor efficiency.
Claims (5)
1, has the centrifugal compressor of bleeding with the jet case structure, contain gas compressor rotating shaft (1), impeller (3), blade (4), impeller back of the body dish (6) and volute (7), described impeller back of the body dish (6) forms vaneless diffuser passage (8) with volute (7), it is characterized in that, having at least 3 on the casing wall of volute (7) is circumferentially uniform bleeding of center-jet guide channel (9) with gas compressor rotating shaft (1), described bleeding-jet guide channel (9) contains bleed-off passage (10) and fluidic channel (14), described bleed-off passage (10) is opened on the casing wall place of vaneless diffuser passage (8) inlet, and this bleed-off passage (10) is perpendicular to this inlet casing wall, described fluidic channel (14) is opened on described volute (7) and twists curvature with the maximum of the runner of blade (4) formation, and the direction of described fluidic channel (14) is identical with the main flow absolute velocity direction at this maximum curvature place; Connect by guide channel (12) between described bleed-off passage (10) and the fluidic channel (14).
2, as claimed in claim 1 have bleed and the centrifugal compressor of jet case structure, it is characterized in that the joint of described bleed-off passage (10) and guide channel (12) forms the spherical air chamber (11) of bleed-off passage.
3, as claimed in claim 1 have bleed and the centrifugal compressor of jet case structure, it is characterized in that the joint of described fluidic channel (14) and guide channel (12) forms the spherical air chamber (13) of fluidic channel.
4, as claimed in claim 1 have bleed and the centrifugal compressor of jet case structure, it is characterized in that the aperture of described bleed-off passage (10), guide channel (12) and fluidic channel (14) is 1~2mm.
5, as claimed in claim 3 have bleed and the centrifugal compressor of jet case structure, it is characterized in that the diameter of spherical air chamber (11) of described bleed-off passage and fluidic channel sphere air chamber (13) is 3~4mm.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CNB2007100635029A CN100451345C (en) | 2007-02-02 | 2007-02-02 | Centrifugal compressor having air removal jet box structure |
Applications Claiming Priority (1)
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CNB2007100635029A CN100451345C (en) | 2007-02-02 | 2007-02-02 | Centrifugal compressor having air removal jet box structure |
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CN101012837A true CN101012837A (en) | 2007-08-08 |
CN100451345C CN100451345C (en) | 2009-01-14 |
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CNB2007100635029A Expired - Fee Related CN100451345C (en) | 2007-02-02 | 2007-02-02 | Centrifugal compressor having air removal jet box structure |
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Cited By (12)
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CN101560987A (en) * | 2008-04-17 | 2009-10-21 | 霍尼韦尔国际公司 | Centrifugal compressor with surge control, and associated method |
CN101737360B (en) * | 2010-02-09 | 2011-03-30 | 清华大学 | Asymmetric self-circulation processing case with slotting width of sine distribution for centrifugal compressor |
CN102011753A (en) * | 2010-02-09 | 2011-04-13 | 清华大学 | Centrifugal compressor asymmetrical self-circulation casing treatment based on variable slot width |
CN101761513B (en) * | 2010-02-09 | 2011-06-15 | 清华大学 | Asymmetric self-circulation processing machine box of centrifugal compressor with arc-shaped grooving widths |
CN103174677A (en) * | 2011-12-20 | 2013-06-26 | 珠海格力电器股份有限公司 | Volute and air conditioner with same |
CN103174678A (en) * | 2013-03-26 | 2013-06-26 | 哈尔滨工程大学 | Centrifugal compressor air guiding recycling structure with multiple channels |
CN104019058A (en) * | 2014-06-27 | 2014-09-03 | 哈尔滨工程大学 | Gas-entraining recycling structure for cartridge receiver of centrifugal-type gas compressor with variable geometric dimension |
CN105065329A (en) * | 2015-08-06 | 2015-11-18 | 中国北方发动机研究所(天津) | Double-rear-slot casing processing device capable of effectively broadening flow range of compressor |
CN105545810A (en) * | 2015-12-18 | 2016-05-04 | 清华大学 | Case of centrifugal compressor |
IT201600106889A1 (en) * | 2016-10-24 | 2018-04-24 | Nuovo Pignone Tecnologie Srl | Diaphragm for centrifugal compressor |
CN108443236A (en) * | 2018-03-05 | 2018-08-24 | 清华大学 | A kind of compressor stator corner separation control device and its control method |
CN113550933A (en) * | 2021-09-22 | 2021-10-26 | 西安空天引擎科技有限公司 | Turbine pump |
Family Cites Families (4)
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JPH11257293A (en) * | 1998-03-11 | 1999-09-21 | Kobe Steel Ltd | Control device of centrifugal compressor |
JP2000205186A (en) * | 1999-01-18 | 2000-07-25 | Ishikawajima Harima Heavy Ind Co Ltd | Centrifugal compressor |
JP4573074B2 (en) * | 2000-05-24 | 2010-11-04 | 株式会社Ihi | Centrifugal compressor with variable diffuser and its control method |
DE10107807C1 (en) * | 2001-02-20 | 2002-07-25 | Man B & W Diesel Ag | Flow machine with radial compressor wheel, used as a turbosupercharger, has cavity between inner cylinder of spiral casing and casing insertion piece |
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2007
- 2007-02-02 CN CNB2007100635029A patent/CN100451345C/en not_active Expired - Fee Related
Cited By (20)
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CN101560987A (en) * | 2008-04-17 | 2009-10-21 | 霍尼韦尔国际公司 | Centrifugal compressor with surge control, and associated method |
CN101560987B (en) * | 2008-04-17 | 2013-07-17 | 霍尼韦尔国际公司 | Centrifugal compressor with surge control, and associated method |
CN101737360B (en) * | 2010-02-09 | 2011-03-30 | 清华大学 | Asymmetric self-circulation processing case with slotting width of sine distribution for centrifugal compressor |
CN102011753A (en) * | 2010-02-09 | 2011-04-13 | 清华大学 | Centrifugal compressor asymmetrical self-circulation casing treatment based on variable slot width |
CN101761513B (en) * | 2010-02-09 | 2011-06-15 | 清华大学 | Asymmetric self-circulation processing machine box of centrifugal compressor with arc-shaped grooving widths |
CN103174677B (en) * | 2011-12-20 | 2016-02-24 | 珠海格力电器股份有限公司 | Volute and air conditioner with same |
CN103174677A (en) * | 2011-12-20 | 2013-06-26 | 珠海格力电器股份有限公司 | Volute and air conditioner with same |
CN103174678A (en) * | 2013-03-26 | 2013-06-26 | 哈尔滨工程大学 | Centrifugal compressor air guiding recycling structure with multiple channels |
CN103174678B (en) * | 2013-03-26 | 2015-09-30 | 哈尔滨工程大学 | Multichannel centrifugal compressor bleed recirculation structure |
CN104019058A (en) * | 2014-06-27 | 2014-09-03 | 哈尔滨工程大学 | Gas-entraining recycling structure for cartridge receiver of centrifugal-type gas compressor with variable geometric dimension |
CN105065329A (en) * | 2015-08-06 | 2015-11-18 | 中国北方发动机研究所(天津) | Double-rear-slot casing processing device capable of effectively broadening flow range of compressor |
CN105545810A (en) * | 2015-12-18 | 2016-05-04 | 清华大学 | Case of centrifugal compressor |
IT201600106889A1 (en) * | 2016-10-24 | 2018-04-24 | Nuovo Pignone Tecnologie Srl | Diaphragm for centrifugal compressor |
WO2018077691A1 (en) * | 2016-10-24 | 2018-05-03 | Nuovo Pignone Tecnologie S.r.l. | Diaphragm for a centrifugal compressor |
CN110050128A (en) * | 2016-10-24 | 2019-07-23 | 诺沃皮尼奥内技术股份有限公司 | Diaphragm for centrifugal compressor |
US10962022B2 (en) | 2016-10-24 | 2021-03-30 | Nuovo Pignone Tecnologie—S.R.L. | Diaphragm for a centrifugal compressor |
CN110050128B (en) * | 2016-10-24 | 2021-10-15 | 诺沃皮尼奥内技术股份有限公司 | Diaphragm for centrifugal compressor |
CN108443236A (en) * | 2018-03-05 | 2018-08-24 | 清华大学 | A kind of compressor stator corner separation control device and its control method |
CN113550933A (en) * | 2021-09-22 | 2021-10-26 | 西安空天引擎科技有限公司 | Turbine pump |
CN113550933B (en) * | 2021-09-22 | 2021-12-21 | 西安空天引擎科技有限公司 | Turbine pump |
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