CN106841676A - A kind of laser-Doppler hydraulic turbine wake measurement device and measuring method - Google Patents
A kind of laser-Doppler hydraulic turbine wake measurement device and measuring method Download PDFInfo
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- CN106841676A CN106841676A CN201710198159.2A CN201710198159A CN106841676A CN 106841676 A CN106841676 A CN 106841676A CN 201710198159 A CN201710198159 A CN 201710198159A CN 106841676 A CN106841676 A CN 106841676A
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- laser
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
- G01P5/26—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting optical wave
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Abstract
The invention discloses a kind of laser-Doppler hydraulic turbine wake measurement device and measuring method, device includes two slide rails parallel with wake flow axis direction, horizontal stand is connected with by support bar on the slide rail, telescopic laser probe support is slidably connected on the horizontal stand, the end of the laser probe support is fixed with laser probe, the laser probe is connected with laser beam emitting device and laser receiver by optical cable, the laser beam emitting device is by generating laser, polarimeter and optical collection element are constituted, the laser receiver is made up of optical collection element and laser pickoff.By the simple and effective optical system of the device, on the premise of wake flow is not disturbed, the real-time flow rate of accurate measurement wake flow each several part.
Description
Technical field
The invention belongs to the discovery techniques field to Ocean Tidal Current Energy, specifically, it is directed to the survey of hydraulic turbine wake flow flow velocity
A kind of laser-Doppler hydraulic turbine wake measurement device and measuring method of amount.
Background technology
Ocean energy be a kind of cleaning, can continuous utilization regenerative resource, aboundresources and effect on environment very little.
In existing ocean energy exploitation, the hydraulic turbine plays vital effect, especially in marine tidal-current energy generation engineering.Scientific research people before
Member research emphasis it is more be the hydraulic turbine runnability rather than its wake flow in itself.Therefore, tidal current energy water turbine wake flow
The measurement work of hydraulic turbine wake flow in basic research, particularly marine tidal-current energy generating field, studies hydraulic turbine hydrodynamics and solves
The engineering problem of the hydraulic turbine has great meaning.
The mainly mechanical rotor current meter of actual hydrologic monitoring system is applied at present, because rotor current meter is by water
Stream promotes blade (or rotation cup) sensor rotation so as to obtain the flow speed value of monitoring position but also inevitable in its course of work
Destroy the kenel in nature flow field, measured flow speed value is not the flow speed value in nature flow field, have impact on certainty of measurement.And
And cannot just be measured when flow velocity too low thrust is not enough to and promotes blade to rotate.Because sensor is that rotatable parts determine that it is feared
Be afraid of that silt is blocked and the winding of pasture and water floating object, certainty of measurement can be influenceed or even cannot be measured.Tsing-Hua University proposes patent of invention《One
Plant double-frequency laser Doppler velocity measurement method and device》(application number：201010220246.1) how general a kind of double-frequency laser is proposed
Speed measuring device, including double-frequency laser Shu Shengcheng and detecting module, frequency mixing module and speed measuring module are strangled, is focused on and is used double-frequency laser
Beam.Xiamen Bo Yida Science and Technology Ltd.s propose patent of invention《Supersonic Doppler flows to current meter》(application number：
201410716599.9) propose that there are a pair points or so the front transducers for being arranged in probe body, formed an angle with body,
Ultrasonic listening flow velocity is used, raising investigative range is focused on.Middle mercury star science and technology (Beijing) Co., Ltd proposes patent of invention《One
Plant Doppler's Flow speed measurer and Doppler's flow velocity measuring system》(application number：201510382016.8) propose to include data
The flow velocity measuring system of the parts such as processing unit, signal measurement unit and wireless communication unit, focuses on signal processing unit.
Doppler laser velocimeter uses laser acquisition flow velocity, and measurement point does not interfere with each other with flow field, is more advanced current measured technology, is mesh
On former world in laboratory, rivers, sea flow measuring widely used capital equipment.It is high with certainty of measurement, broad quantum, sensing
It is sensitive, the advantages of high resolution.LDV uses modern age light --- the LDV systems of electronics and Microprocessor technology
System, can with comparalive ease realize the measurement of the flowings such as two dimension, three-dimensional, and obtain the quantitative information of various complex flow structures.
Therefore laser doppler technique has attracted the research worker of substantial amounts of experimental fluid mechanics and Other subjects to go to study and solve
These problems, are developed rapidly laser Doppler velocity technique, the powerful as flow measurement experiment.
The content of the invention
The invention aims to overcome deficiency of the prior art, there is provided a kind of laser-Doppler hydraulic turbine wake flow is surveyed
Amount device and measuring method.The device by simple and effective optical system, on the premise of wake flow is not disturbed, accurate measurement tail
Flow the real-time flow rate of each several part.
The purpose of the present invention is achieved through the following technical solutions：
A kind of laser-Doppler hydraulic turbine wake measurement device, including two slide rails parallel with wake flow axis direction, institute
State and horizontal stand is connected with by support bar on slide rail, telescopic laser probe branch is slidably connected on the horizontal stand
Frame, the end of the laser probe support is fixed with laser probe, and the laser probe is connected with Laser emission and fills by optical cable
Put and laser receiver, the laser beam emitting device is made up of generating laser, polarimeter and optical collection element, it is described to swash
Optical pickup apparatus are made up of optical collection element and laser pickoff.
The horizontal direction of the horizontal stand is provided with the slideway for the laser probe bracket slide.
The laser probe support can be realized flexible vertically and moved horizontally.
The laser probe and laser probe support are articulated and connected, and two kinds of positions of opposed vertical and Relative vertical can be kept to close
System.
The polarimeter may filter that the laser beam polarized by fixed-direction.
The generating laser and polarimeter are respectively arranged with two.
A kind of measuring method of laser-Doppler hydraulic turbine wake measurement device, comprises the following steps：
(1) laser beam emitting device is opened, adjustment laser probe backing positions make laser probe focus vertically region to be measured；
(2) controlling polarimeter makes the two beam laser polarization directions that laser probe is launched be wake flow axis direction, according to how general
Strangle effect and obtain regional flow to be measured along the velocity component V on wake flow axis directionx；
(3) adjustment polarimeter makes the two beam laser polarization directions that laser probe is launched be the vertical direction of wake flow axial direction, root
The horizontal velocity component V on the axially vertical direction of regional flow to be measured is obtained according to Doppler effecty；
(4) adjustment laser probe backing positions make laser probe level focusing region to be measured；
(5) controlling polarimeter makes the two beam laser polarization directions that laser probe is launched be wake flow axis direction, according to how general
Strangle effect and obtain regional flow to be measured along the velocity component V on wake flow axis directionx’；
(6) adjustment polarimeter makes the two beam laser polarization directions that laser probe is launched be the vertical direction of wake flow axial direction, root
The vertical velocity component V on the axially vertical direction of regional flow to be measured is obtained according to Doppler effectz。
Compared with prior art, the beneficial effect that technical scheme is brought is：
1. using the mechanical rotor current meter that laser in place is traditional in the present invention, in rotor current meter work, when current are pushed away
Also the kenel in nature flow field is destroyed while dynamic sensor rotation, thus such current meter measure be not nature flow field stream
Speed value, have impact on certainty of measurement, using the laser-Doppler method in the present invention, effectively prevent and hydraulic turbine wake flow is disturbed
It is dynamic.
2. laser doppler is used, and certainty of measurement is higher.
3. the present invention can flexibly control laser convergent point, can detect whole wake flow water velocity everywhere and overall change
Law.
4. the wake flow speed measured by the present invention is actual water velocity, more more convincing than software simulation, to water wheels
The research of tail stream provides true basis.
Brief description of the drawings
Fig. 1 is a kind of overall structure diagram of laser-Doppler hydraulic turbine wake measurement device of the invention.
Fig. 2 is laser Doppler velocimetry working light path schematic diagram.
Fig. 3 is measuring principle schematic diagram in area's to be measured.
Reference：1- slide rails, 2- support bars, 3- horizontal stands, 4- laser probe supports, 5- laser probes, 6- is to be measured
Region, 7- laser beam emitting devices, 8- laser receivers, 9- optical cables, 10- generating lasers, 11- polarimeters, 12- converging lenses,
13- scatters light converging lenses, 14- laser pickoffs
Specific embodiment
The present invention is further illustrated below in conjunction with the accompanying drawings：
As shown in figure 1, the present invention provides a kind of laser-Doppler hydraulic turbine wake measurement device, including along wake flow axis side
To slide rail 1, the horizontal stand 3 that can be moved freely along axis is connected with by support bar 2 on slide rail 1, on horizontal stand 3
Slideway is provided with, be slidably connected the laser probe support 4 that can be moved along the horizontal direction of horizontal stand 3, laser by the slideway
The end that probe bracket 4 has Telescopic, laser probe support 4 is hinged laser probe 5, and laser probe 5 can be by branch of popping one's head in
The flexible realization of frame 4 is transferred up and down, and laser beam emitting device 7 and laser receiver 8 are respectively provided at both sides in the present embodiment
On support bar 2, laser beam emitting device 7 and laser receiver 8 are connected with laser probe 5 respectively by optical cable 9, by laser
The scattering laser that probe 5 is received, sending optical signal to laser receiver 8 by optical cable 9 carries out signal transacting and calculates to treat
Area's water velocity is surveyed, it is wherein visible in the hydraulic turbine wake flow figure of region 6 to be measured.
As shown in Fig. 2 the present embodiment provides laser Doppler velocimetry working light path schematic diagram, wherein laser beam emitting device 7
Including two generating lasers, 10, two polarimeters 11 and converging lenses 12；Laser receiver 8 includes the He of scattering light converging lenses 13
Laser pickoff 14.
Process when specifically being measured by the measurement apparatus is as follows：
The present invention operationally, as shown in figure 1, first opening laser beam emitting device 7, adjusts the position of laser probe support 4,
Make laser probe 5 for location A, region to be measured 6 of focusing vertically；Control laser polarimeter 11, makes two beam laser polarization directions be tail
Stream axis direction, because interference effect is produced along the interference fringe on wake flow axis direction on its laser convergent point, due to water
There is frequency displacement in the particulate in stream, then collect frequency shift signal by laser receiver 8 to the Doppler effect of interference region, after
Continuous processing of circuit, current are calculated along the velocity component V on wake flow axis direction by measuring frequency displacement according to formulax；Further adjust
Whole laser polarimeter 11 makes laser polarization direction for axially vertical direction, similarly measures the axially vertical side of the current of region to be measured 6
Upward horizontal velocity component Vy。
Then adjustment laser probe support 4 and laser probe 5 are position B, make its level focusing region 6 to be measured.Control swashs
Photopolarimeter 11, makes two beam laser polarization directions for wake flow axis direction, because interference effect is produced on its laser convergent point
Along the interference fringe on wake flow axis direction, because the particulate in current is to the Doppler effect of interference region, there is frequency displacement, then by
Laser receiver collects frequency shift signal, is processed by subsequent conditioning circuit, and current are calculated along wake flow according to formula by measuring frequency displacement
Velocity component V on axis directionx', and the current axial velocity component V that can be measured in position A with laser probe 5xRelatively
According to.Further adjustment laser polarimeter makes laser polarization direction for axially vertical direction, similarly measures the axle of the current of region to be measured 6
To the vertical velocity component V in vertical directionz。
With VxAs a example by, as shown in figure 3, two beam laser on convergent point because interference effect produces the intersecting bar of one group of light and shade
Line.Although the analysis for Doppler signal some characteristics (such as signal to noise ratio, visibility) not fully meets reality, apply
It is simple and clear that the concept of interference fringe solves problems.Interference fringe spacing is：
Δ x=λ/2sin θ
When in current fine particle with speed Vx, during by measured zone, particle will pass through these parallel interference fringes,
In bright fringes area, KPT Scatter light intensity.Therefore the light intensity being collected into photo-detector is passed through the velocity perturbation pair of striped by particle
Optical signal is debugged, and light intensity change frequency meets:
According to the frequency shift signal that laser receiver is collected into, you can calculate Vx。
The present invention is not limited to embodiments described above.Description to specific embodiment above is intended to describe and says
Bright technical scheme, above-mentioned specific embodiment is only schematical, is not restricted.This is not being departed from
In the case of invention objective and scope of the claimed protection, one of ordinary skill in the art may be used also under enlightenment of the invention
The specific conversion of many forms is made, these are belonged within protection scope of the present invention.
Claims (7)
1. a kind of laser-Doppler hydraulic turbine wake measurement device, it is characterised in that including parallel with wake flow axis direction two
Individual slide rail, horizontal stand is connected with the slide rail by support bar, is slidably connected on the horizontal stand telescopic sharp
Light probe support, the end of the laser probe support is fixed with laser probe, and the laser probe is connected with sharp by optical cable
Light emitting devices and laser receiver, the laser beam emitting device is by generating laser, polarimeter and optical collection element group
Into the laser receiver is made up of optical collection element and laser pickoff.
2. a kind of laser-Doppler hydraulic turbine wake measurement device according to claim 1, it is characterised in that the level branch
The horizontal direction of frame is provided with the slideway for the laser probe bracket slide.
3. a kind of laser-Doppler hydraulic turbine wake measurement device according to claim 1, it is characterised in that the laser is visited
Head bracket can be realized flexible vertically and moved horizontally.
4. a kind of laser-Doppler hydraulic turbine wake measurement device according to claim 1, it is characterised in that the laser is visited
Head and laser probe support are articulated and connected, and can keep two kinds of position relationships of opposed vertical and Relative vertical.
5. a kind of laser-Doppler hydraulic turbine wake measurement device according to claim 1, it is characterised in that the polarimeter
May filter that the laser beam polarized by fixed-direction.
6. a kind of laser-Doppler hydraulic turbine wake measurement device according to claim 1, it is characterised in that the laser hair
Emitter and polarimeter are respectively arranged with two.
7. a kind of measuring method of laser-Doppler hydraulic turbine wake measurement device according to claim 1, it is characterised in that
Comprise the following steps：
(1) laser beam emitting device is opened, adjustment laser probe backing positions make laser probe focus vertically region to be measured；
(2) controlling polarimeter makes the two beam laser polarization directions that laser probe is launched be wake flow axis direction, is imitated according to Doppler
Regional flow to be measured should be obtained along the velocity component V on wake flow axis directionx；
(3) adjustment polarimeter makes the two beam laser polarization directions that laser probe is launched be the vertical direction of wake flow axial direction, according to many
It is general to strangle the horizontal velocity component V that effect is obtained on the axially vertical direction of regional flow to be measuredy；
(4) adjustment laser probe backing positions make laser probe level focusing region to be measured；
(5) controlling polarimeter makes the two beam laser polarization directions that laser probe is launched be wake flow axis direction, is imitated according to Doppler
Regional flow to be measured should be obtained along the velocity component V on wake flow axis directionx’；
(6) adjustment polarimeter makes the two beam laser polarization directions that laser probe is launched be the vertical direction of wake flow axial direction, according to many
It is general to strangle the vertical velocity component V that effect is obtained on the axially vertical direction of regional flow to be measuredz。
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| Application Number | Priority Date | Filing Date | Title |
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| CN201710198159.2A CN106841676A (en) | 2017-03-29 | 2017-03-29 | A kind of laser-Doppler hydraulic turbine wake measurement device and measuring method |
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| CN201710198159.2A CN106841676A (en) | 2017-03-29 | 2017-03-29 | A kind of laser-Doppler hydraulic turbine wake measurement device and measuring method |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108801584A (en) * | 2017-10-17 | 2018-11-13 | 沈熊 | Wave current flow velocity measuring system, water hole formula swimming machine system based on Laser Doppler speed and velocity correction method |
| CN109655634A (en) * | 2018-12-18 | 2019-04-19 | 西华大学 | A kind of detection method of pump turbine tail water velocity in pipes |
| CN109974640A (en) * | 2017-12-27 | 2019-07-05 | 核动力运行研究所 | A kind of fuel assembly deformation detection probe rack position adaptive device |
| CN111693730A (en) * | 2020-07-02 | 2020-09-22 | 德州尧鼎光电科技有限公司 | Photoelectric current meter for near-wall flow velocity measurement and velocity measurement method |
| CN114019586A (en) * | 2021-11-16 | 2022-02-08 | 刘天健 | Rainfall detection method based on base station and base station |
| CN115839821A (en) * | 2023-02-21 | 2023-03-24 | 中国空气动力研究与发展中心空天技术研究所 | Turbine internal flow laser Doppler coaxial measuring device and debugging and testing method thereof |
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| CN202631566U (en) * | 2012-03-07 | 2012-12-26 | 中国计量学院 | Double-beam laser Doppler tachymeter |
| CN205091352U (en) * | 2015-11-06 | 2016-03-16 | 三峡大学 | Support is measured to current meter |
| CN105738650A (en) * | 2014-12-12 | 2016-07-06 | 西安丁子电子信息科技有限公司 | Apparatus capable of measuring vector wind speed |
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| US4919536A (en) * | 1988-06-06 | 1990-04-24 | Northrop Corporation | System for measuring velocity field of fluid flow utilizing a laser-doppler spectral image converter |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108801584A (en) * | 2017-10-17 | 2018-11-13 | 沈熊 | Wave current flow velocity measuring system, water hole formula swimming machine system based on Laser Doppler speed and velocity correction method |
| CN108801584B (en) * | 2017-10-17 | 2024-04-02 | 沈熊 | Wave flow velocity measurement system based on laser Doppler velocity measurement, water tunnel type swimming machine system and velocity correction method |
| CN109974640A (en) * | 2017-12-27 | 2019-07-05 | 核动力运行研究所 | A kind of fuel assembly deformation detection probe rack position adaptive device |
| CN109974640B (en) * | 2017-12-27 | 2023-12-26 | 核动力运行研究所 | Position adapting device for deformation detection probe frame of fuel assembly |
| CN109655634A (en) * | 2018-12-18 | 2019-04-19 | 西华大学 | A kind of detection method of pump turbine tail water velocity in pipes |
| CN111693730A (en) * | 2020-07-02 | 2020-09-22 | 德州尧鼎光电科技有限公司 | Photoelectric current meter for near-wall flow velocity measurement and velocity measurement method |
| CN114019586A (en) * | 2021-11-16 | 2022-02-08 | 刘天健 | Rainfall detection method based on base station and base station |
| CN115839821A (en) * | 2023-02-21 | 2023-03-24 | 中国空气动力研究与发展中心空天技术研究所 | Turbine internal flow laser Doppler coaxial measuring device and debugging and testing method thereof |
| CN115839821B (en) * | 2023-02-21 | 2023-04-28 | 中国空气动力研究与发展中心空天技术研究所 | Turbine internal flow laser Doppler coaxial measuring device and debugging and testing method thereof |
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