CN105818951B - Novel preposition skew back guide-vane pump-jet propulsor and its design method - Google Patents
Novel preposition skew back guide-vane pump-jet propulsor and its design method Download PDFInfo
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- CN105818951B CN105818951B CN201610019456.1A CN201610019456A CN105818951B CN 105818951 B CN105818951 B CN 105818951B CN 201610019456 A CN201610019456 A CN 201610019456A CN 105818951 B CN105818951 B CN 105818951B
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- Prior art keywords
- guide vane
- skew back
- postposition
- impeller
- preposition
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63H—MARINE PROPULSION OR STEERING
- B63H11/00—Marine propulsion by water jets
- B63H11/02—Marine propulsion by water jets the propulsive medium being ambient water
- B63H11/04—Marine propulsion by water jets the propulsive medium being ambient water by means of pumps
- B63H11/08—Marine propulsion by water jets the propulsive medium being ambient water by means of pumps of rotary type
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63H—MARINE PROPULSION OR STEERING
- B63H11/00—Marine propulsion by water jets
- B63H11/02—Marine propulsion by water jets the propulsive medium being ambient water
- B63H11/04—Marine propulsion by water jets the propulsive medium being ambient water by means of pumps
- B63H2011/046—Marine propulsion by water jets the propulsive medium being ambient water by means of pumps comprising means for varying pump characteristics, e.g. rotary pumps with variable pitch impellers, or adjustable stators
Abstract
The present invention provides a kind of novel preposition skew back guide-vane pump-jet propulsor and its design methods, including preposition skew back guide vane, postposition impeller, annular conduit, spring bearing, rotary shaft, wherein guide vane wheel hub and postposition impeller are coaxially disposed in the inside of annular conduit；Preposition skew back guide vane uniform pitch is set to the outer wall of guide vane wheel hub and is fixedly connected with annular conduit；Rotary shaft sequentially coaxially passes through guide vane wheel hub and postposition impeller, and rotation shaft end is provided with fair water cone, and postposition impeller is between guide vane wheel hub and fair water cone；Postposition impeller is fixedly sheathed in outside rotary shaft and is driven by rotary shaft and done work, and the sliding support coaxial bearing that rotary shaft passes through is supported in guide vane hub interior.Radiated noise is effectively reduced in the present invention, improves structural strength, and the shock resistance and low noise for being suitable for underwater sailing body promote.
Description
Technical field
The invention belongs to pump hydraulic jet propulsion field, and in particular to a kind of novel preposition skew back guide-vane pump-jet propulsor and its
Design method.
Background technique
With the generation of horse boat MH370 boat difficult matter part and the development of related search-and-rescue work, the U.S. " bluefin tuna " is autonomous
Formula aircraft constantly enters the sight of people, and the common people have further insight to the importance of underwater detectoscope.Sound stealth
It is the important leverage that one of important performance indexes of underwater sailing body and underwater sailing body complete mission task, it not only determines
Determine the sphere of action of itself sonar and signal receiving device, while also significantly affecting itself by the general of other side's sonar detection
Rate.Propeller plays to pass underwater sailing body Sound stealth performance as the core composition in underwater sailing body propulsion system
Important role.This is because: on the one hand, with the appearance of the damping noise reductions technology such as cabin Bo, buoyant raft, vibration isolator, flexible connecting pipe,
The mechanical noise of underwater sailing body has gradually obtained effective improvement and control；On the other hand, propeller is via the straight of inlet pipeline
Connecing radiated noise is that can not be eliminated by device for vibration insutation, radiated noise reduce can only by the design of noise-reduced propeller come
It solves.
Summary of the invention
The purpose of the present invention is to the defects of the prior art, provide a kind of novel preposition skew back guide-vane pump spray propulsion
Radiated noise is effectively reduced in device and its design method, improves structural strength, is suitable for shock resistance and the low noise of underwater sailing body
It promotes.
The present invention provides a kind of novel preposition skew back guide-vane pump-jet propulsors, including preposition skew back guide vane, postposition leaf
Wheel, annular conduit, spring bearing, rotary shaft, wherein guide vane wheel hub and postposition impeller are coaxially disposed in the inside of annular conduit；
Preposition skew back guide vane uniform pitch is set to the outer wall of guide vane wheel hub and is fixedly connected with annular conduit；Rotary shaft is sequentially coaxially worn
Guide vane wheel hub and postposition impeller are crossed, rotation shaft end is provided with fair water cone, and postposition impeller is between guide vane wheel hub and fair water cone；
Postposition impeller is fixedly sheathed in outside rotary shaft and is driven by rotary shaft and done work, the sliding support coaxial bearing branch that rotary shaft passes through
It supports in guide vane hub interior.
The postposition impeller inlet circular rector is equal to the circular rector of preposition skew back guide vane outlet.
A kind of design method of novel preposition skew back guide-vane pump-jet propulsor, comprising the following steps:
A. flow, lift, revolving speed the inlet and outlet size of hydraulic propeller and the definition of lift are pumped according to target, calculated
The blade of postposition impeller imports and exports circular rector out；
B. three features above sections are selected in postposition impeller blade radial direction, wherein choosing postposition impeller hub radius
Place section is a characteristic cross-section, and section is remaining as another characteristic cross-section where choosing postposition wheel rim radius
Characteristic cross-section is uniformly being chosen between section where section where postposition impeller hub radius and postposition wheel rim radius, will most
The characteristic cross-section in section is as circular rector maximum cross-section where close to postposition wheel rim radius；
C. a is walked into calculated postposition impeller inlet and outlet circular rector as the circular rector value of circular rector maximum cross-section, postposition impeller
The inlet and outlet circular rector value in section is taken as circular rector maximum cross-section circular rector value multiplied by hub diameter ratio multiple, postposition impeller where hub radius
Section inlet and outlet circular rector value where flange radius is taken as 0.5 times of circular rector maximum cross-section circular rector value or hereinafter, remaining feature is cut
Face disengaging circular rector value is acquired by linear interpolation；
D. the circular rector value of preposition skew back guide vane outlet is the circular rector of postposition impeller inlet；
E. postposition impeller and preposition is completed according to the circular rector of the circular rector of preposition skew back guide vane outlet and postposition impeller inlet and outlet
The three Dimensional Design of skew back guide vane blade；
F. the skew back ratio of preposition skew back guide vane blade is chosen, wherein skew back ratio is 50% or more, and skew back angle is along leaf
Piece radially uses linear distribution form；
G. conduit outer wall face shape is chosen, using the preferable airfoil structure of mobile performance；
H. it by high-performance calculation machine platform, is calculated with propulsive performance of the numerical experimentation means to pump-jet propulsor
And assessment；
I. judge whether design result meets design objective, if not meeting design objective, loop iteration design will be carried out, no
Circular rector, the skew back angle of preposition skew back guide vane blade of disconnected modification postposition impeller and preposition skew back guide vane blade are set until meeting
Count index.
Preposition inclination guide vane of the invention is in the front of postposition impeller influent stream, on the one hand makes the influent stream of work doing impeller more
Uniformly, on the other hand make the stator-rotor interaction region for pumping hydraulic propeller in the front of work doing impeller, intensity will be significantly less than
The stator-rotor interaction that high speed and high pressure outlet area after impeller acting occurs.Preposition skew back guide vane of the invention makes ship/ship tail height
Wake area enters impeller inlet along guide vane radius section gradually, to achieve the purpose that reduce impeller blade exciting force.Meanwhile
The skew back and torsional deformation of work doing impeller can be effectively reduced using preposition skew back guide vane in the present invention, and then is effectively increased leaf
Wheel construction intensity.Preposition inclination guide vane leaf of the invention slightly suitably reduces load and matches with impeller loads, has reached inhibition pump
Spray impeller is slightly vortexed purpose that is dynamic and reducing propulsion noise.
Detailed description of the invention
Fig. 1 is schematic structural view of the invention a；
Fig. 2 is schematic structural view of the invention b；
Wherein, the preposition skew back guide vane of 1-；2- postposition impeller；3- conduit；4- fair water cone；5- guide vane wheel hub；6- spring bearing；
7- rotary shaft, section where 8- postposition impeller hub radius, section where 9- postposition wheel rim radius.
Specific embodiment
The following further describes the present invention in detail with reference to the accompanying drawings and specific embodiments, convenient for this hair is well understood
It is bright, but they limiting the invention.
As shown, the present invention provides a kind of novel preposition skew back guide-vane pump-jet propulsors, it is characterised in that: it is wrapped
Preposition skew back guide vane 1, postposition impeller 2, annular conduit 3, spring bearing 6, rotary shaft 7 are included, wherein guide vane wheel hub 5 and postposition impeller
2 coaxial arrangements are in the inside of annular conduit 3；Preposition 1 uniform pitch of skew back guide vane is set to the outer wall of guide vane wheel hub 5 and and ring
Shape conduit 3 is fixedly connected；Rotary shaft 7 sequentially coaxially passes through guide vane wheel hub 5 and postposition impeller 2, and 7 end of rotary shaft is provided with water conservancy diversion
Cap 4, postposition impeller 2 is between guide vane wheel hub 5 and fair water cone 4；Postposition impeller 2 is fixedly sheathed in 7 outside of rotary shaft and by revolving
The driving acting of shaft 7,6 coaxial support of sliding support bearing that rotary shaft 7 passes through is inside guide vane wheel hub 5.The postposition impeller 2
Import circular rector is equal to the circular rector of preposition skew back guide vane 2 outlet.
The design method of above-mentioned novel preposition skew back guide-vane pump-jet propulsor the following steps are included:
A. flow, lift, revolving speed the inlet and outlet size of hydraulic propeller and the definition of lift are pumped according to target, calculated
The blade of postposition impeller imports and exports circular rector out.The power of blade acting is indicated when calculating using blade loading size, actually
Load distribution is blade swirl distribution.The inlet and outlet circular rector difference of pump class propeller determines the lift of propeller, the height of lift
The low size for determining propeller acting ability.According to the definition lift Ht=of lift in " modern times pump is theoretical and designs "
ω(г2-г1)/(2g π), wherein ω indicates angular speed, the π of г=2 RvuIndicate that the circular rector of impeller section, subscript 1 and 2 represent import
The outlet port and.
B. 5 characteristic cross-sections are selected in postposition impeller blade radial direction, wherein where choosing postposition impeller hub radius
Section 8 be percentage as 0 characteristic cross-section, choose postposition wheel rim radius where section 9 as percentage as 1 spy
Levy section, remaining characteristic cross-section uniformly chooses between postposition impeller hub and postposition wheel rim, postposition impeller hub with
Select three characteristic cross-sections 25% between postposition wheel rim, 50%, 75%, it will make closest to 1 percentage characteristic cross-section
For circular rector maximum cross-section, i.e., using 75% characteristic cross-section as circular rector maximum cross-section；
C. a is walked into calculated postposition impeller inlet and outlet circular rector as the circular rector value of circular rector maximum cross-section, percentage 0
The inlet and outlet circular rector value of characteristic cross-section be taken as circular rector maximum cross-section circular rector value multiplied by hub diameter ratio multiple, the spy that percentage is 1
The inlet and outlet circular rector value in sign section is taken as 0.5 times of circular rector maximum cross-section circular rector value or hereinafter, other characteristic cross-sections pass in and out ring
Measurement value is acquired by linear interpolation；
D. the circular rector value of preposition skew back guide vane outlet is the circular rector of postposition impeller inlet, is the preposition inclination guide vane of matching
Load and postposition impeller loads.In addition, vacuole is the important noise of propeller according to the practical experience that noise-reduced propeller designs
Source, and propeller blade ending is the highest position of linear velocity, and is easiest to the position for vacuole occur.The present invention passes through reduction
The load (circular rector) of preposition skew back guide vane leaf slightly achievees the purpose that pump spray impeller is inhibited slightly to be vortexed dynamic and reduction propulsion noise.
E. postposition impeller and preposition is completed according to the circular rector of the circular rector of preposition skew back guide vane outlet and postposition impeller inlet and outlet
The three Dimensional Design (bibliography " mixed-flow water jet propulsion pump three Dimensional Design and numerical experimentation ", Jin Shuanbao) of skew back guide vane blade；
F. the skew angle of preposition skew back guide vane blade is chosen, wherein skew back ratio is 50% or more, and skew back angle is along leaf
Piece radially uses linear distribution form；So that the high wake area of ship/ship tail enters impeller inlet along guide vane radius section gradually,
To achieve the purpose that reduce impeller blade exciting force.Meanwhile work doing impeller can be effectively reduced using skew back guide vane in the present invention
Skew back and torsional deformation, and then be effectively increased blade wheel structure intensity.Wherein blade skew angle refers to the side of blade tip section
Oblique angle, referred to as 100% skew back when blade rake angle displacement is exactly equal to 360 °/Z (Z is the number of blade), when skew back is greater than or waits
Referred to as big skew back when 50%.
G. conduit outer wall face shape is chosen, using the preferable airfoil structure of mobile performance；
H. it by high-performance calculation machine platform, is calculated with propulsive performance of the numerical experimentation means to pump-jet propulsor
With assessment (bibliography " the hydraulic propeller Transform Type design based on numerical experimentation and on-board testing ", Jin Shuanbao)；
I. judge whether design result meets design objective, if not meeting design objective, loop iteration design will be carried out, no
Circular rector, the skew back angle of preposition skew back guide vane blade of disconnected modification postposition impeller and preposition skew back guide vane blade are set until meeting
Count index.
The content that this specification is not described in detail belongs to the prior art well known to professional and technical personnel in the field.
Claims (2)
1. a kind of novel preposition skew back guide-vane pump-jet propulsor, it is characterised in that: it includes preposition skew back guide vane (1), postposition
Impeller (2), annular conduit (3), spring bearing (6), rotary shaft (7), wherein guide vane wheel hub (5) and postposition impeller (2) are coaxial
It is set to the inside of annular conduit (3)；Preposition skew back guide vane (1) uniform pitch is set to the outer wall of guide vane wheel hub (5) and and ring
Shape conduit (3) is fixedly connected；Rotary shaft (7) sequentially coaxially passes through guide vane wheel hub (5) and postposition impeller (2), rotary shaft (7) end
It is provided with fair water cone (4), postposition impeller (2) is located between guide vane wheel hub (5) and fair water cone (4)；Postposition impeller (2) is fixedly attached
It is external in rotary shaft (7) and driven and do work by rotary shaft (7), sliding support bearing (6) coaxial support that rotary shaft (7) passes through in
Guide vane wheel hub (5) is internal；Preposition inclination guide vane is in the front of postposition impeller influent stream；Before postposition impeller (2) import circular rector is equal to
Set the circular rector of skew back guide vane (2) outlet；The high wake area of ship/ship tail enters impeller inlet along guide vane radius section gradually；Before
Inclination guide vane leaf slightly load is set to match with impeller loads；The skew back ratio of preposition skew back guide vane blade is 50% or more, skew angle
Degree uses linear distribution form along blade radial；Conduit outer wall face shape, using the preferable airfoil structure of mobile performance.
2. the design method of novel preposition skew back guide-vane pump-jet propulsor described in claim 1, it is characterised in that including with
Lower step:
A. flow, lift, revolving speed the inlet and outlet size of hydraulic propeller and the definition of lift are pumped according to target, after calculating
Set the blade inlet and outlet circular rector of impeller；The power of blade acting, actually load are indicated when calculating using blade loading size
Distribution is blade swirl distribution；
B. 5 characteristic cross-sections are selected in postposition impeller blade radial direction, wherein choosing section where postposition impeller hub radius
It is percentage as 0 characteristic cross-section, section where choosing postposition wheel rim radius is cut as percentage as 1 feature
Face, remaining characteristic cross-section are uniformly chosen between postposition impeller hub and postposition wheel rim, postposition impeller hub and postposition
Select three characteristic cross-sections 25% between wheel rim, 50%, 75%, using closest to 1 percentage characteristic cross-section as ring
Maximum cross-section is measured, i.e., using 75% characteristic cross-section as circular rector maximum cross-section；
C. a is walked into calculated postposition impeller inlet and outlet circular rector as the circular rector value of circular rector maximum cross-section, postposition impeller hub
The inlet and outlet circular rector value in section is taken as circular rector maximum cross-section circular rector value multiplied by hub diameter ratio multiple, postposition wheel rim where radius
Section inlet and outlet circular rector value where radius be taken as 0.5 times of circular rector maximum cross-section circular rector value or hereinafter, remaining characteristic cross-section into
Circular rector value is acquired by linear interpolation out；
D. the circular rector value of preposition skew back guide vane outlet is the circular rector of postposition impeller inlet；
E. postposition impeller and preposition skew back are completed according to the circular rector of the circular rector of preposition skew back guide vane outlet and postposition impeller inlet and outlet
The three Dimensional Design of guide vane blade；
F. the skew back ratio of preposition skew back guide vane blade is chosen, wherein skew back ratio is 50% or more, and skew back angle is along blade diameter
To using linear distribution form；
G. conduit outer wall face shape is chosen, using the preferable airfoil structure of mobile performance；
H. it by high-performance calculation machine platform, is calculated and is commented with propulsive performance of the numerical experimentation means to pump-jet propulsor
Estimate；
I. judge whether design result meets design objective, if not meeting design objective, loop iteration design will be carried out, constantly repaired
Change the circular rector of postposition impeller and preposition skew back guide vane blade, the skew back angle of preposition skew back guide vane blade, refers to until meeting design
Mark.
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| CN106844878A (en) * | 2016-12-28 | 2017-06-13 | 中国人民解放军海军工程大学 | Pump-jet propulsor multiple target fast optimal design method |
| CN106951623B (en) * | 2017-03-14 | 2020-10-02 | 中国人民解放军海军工程大学 | Pump jet propeller hydraulic model with Helmholtz resonant cavity and design method thereof |
| CN108313249A (en) * | 2017-12-20 | 2018-07-24 | 中国船舶重工集团公司第七0研究所 | Pump-jet propulsor lightweight combined-stator conduit and its forming method |
| CN110104154A (en) * | 2019-04-27 | 2019-08-09 | 江苏大学镇江流体工程装备技术研究院 | A kind of pump-jet propulsor |
| CN110329478A (en) * | 2019-06-18 | 2019-10-15 | 珠海超弦智能科技有限公司 | A kind of pressurization water conservancy diversion spout for marine propeller |
| CN111470018A (en) * | 2020-05-12 | 2020-07-31 | 韩玉军 | Pod electric pump jet propeller |
| CN111645838B (en) * | 2020-06-15 | 2021-04-06 | 中国船舶科学研究中心 | Pipe oar supports subregion guiding device that prerevolves |
| CN112115562A (en) * | 2020-09-21 | 2020-12-22 | 中国人民解放军海军工程大学 | Pump-jet propeller with blade tip circular ring embedded in guide pipe groove and design method thereof |
| CN116353802B (en) * | 2023-05-25 | 2023-09-08 | 合肥倍豪海洋装备技术有限公司 | Inflow auxiliary device and propeller with same |
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