1、BS ISO15769:2010ICS 17.120.20NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDHydrometry Guidelines for theapplication of acousticvelocity meters usingthe Doppler and echocorrelation methodsThis British Standard was published under the authority of the Standards
2、Policy and Strategy Committee on 31 May 2010. BSI 2010ISBN 978 0 580 59637 7Amendments/corrigenda issued since publicationDate CommentsBS ISO 15769:2010National forewordThis British Standard is the UK implementation of ISO 15769:2010. Itsupersedes BS ISO/TS 15769:2000 which is withdrawn.The UK parti
3、cipation in its preparation was entrusted to TechnicalCommittee CPI/113/1, Velocity area methods.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Users are responsi
4、ble for its correct application. Compliance with a British Standard cannot confer immunityfrom legal obligations.BS ISO 15769:2010Reference numberISO 15769:2010(E)ISO 2010INTERNATIONAL STANDARD ISO15769First edition2010-04-15Hydrometry Guidelines for the application of acoustic velocity meters using
5、 the Doppler and echo correlation methods Hydromtrie Lignes directrices pour lapplication des compteurs de vitesse ultrasoniques fixes utilisant leffet Doppler et la corrlation dchos BS ISO 15769:2010ISO 15769:2010(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Ad
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8、re has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. COPYRIGHT PROTECTED DOCUMENT ISO 2010 All rights reserved. Unless otherwise specified, n
9、o part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case post
10、ale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2010 All rights reservedBS ISO 15769:2010ISO 15769:2010(E) ISO 2010 All rights reserved iiiContents Page Foreword .v 1 Scope1 2 Normative references1 3 Terms,
11、 definitions and abbreviated terms1 3.1 Terms and definitions .1 3.2 Abbreviated terms .3 4 Principles of operation of the techniques.3 4.1 Ultrasonic Doppler 3 4.2 Operating techniques5 4.3 Bed-mounted Doppler systems .6 4.4 Side-looking/horizontal ADCPs .6 4.5 Acoustic (echo) correlation method8 4
12、.6 Velocity-index ratings .11 5 Factors affecting operation and accuracy11 5.1 General .11 5.2 Characteristics of the instrument 11 5.3 Channel and water characteristics 16 5.4 Effect of weed 20 6 Site selection .20 6.1 General .20 6.2 General site requirements for Dopplers and echo correlation devi
13、ces.20 6.3 Bed-mounted ultrasonic Doppler and echo correlation devices .21 6.4 Side-lookers .22 7 Measurements .22 7.1 Velocity.22 7.2 Water level23 7.3 Determination of cross-sectional area23 8 Installation, operation and maintenance.23 8.1 Installation considerations.23 8.2 General maintenance con
14、siderations .25 9 Calibration, evaluation and verification 26 9.1 General .26 9.2 Calibration and performance checking.26 10 Determination of discharge27 10.1 General .27 10.2 Velocity-index ratings .28 11 Uncertainties in discharge determinations.32 11.1 General .32 11.2 Definition of uncertainty .
15、32 11.3 General expectations of performance.33 11.4 Methodology of estimating the uncertainty in discharge determination 33 12 Points to consider when selecting equipment.38 Annex A (informative) Selection considerations for ultrasonic Doppler and echo correlation devices39 Annex B (informative) Pra
16、ctical considerations 41 BS ISO 15769:2010ISO 15769:2010(E) iv ISO 2010 All rights reservedAnnex C (informative) Introduction to measurement uncertainty45 Annex D (informative) Performance guide for hydrometric equipment for use in technical standards53 Annex E (informative) Sample questionnaire Dop
17、pler- and echo-correlation-based flowmeters56 Bibliography 61 BS ISO 15769:2010ISO 15769:2010(E) ISO 2010 All rights reserved vForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing Internati
18、onal Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with IS
19、O, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical co
20、mmittees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the
21、 possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 15769 was prepared by Technical Committee ISO/TC 113, Hydrometry, Subcommittee SC 1, Velocity area methods. This first edi
22、tion of ISO 15769 cancels and replaces ISO/TS 15769:2000, which has been technically revised. BS ISO 15769:2010BS ISO 15769:2010INTERNATIONAL STANDARD ISO 15769:2010(E) ISO 2010 All rights reserved 1Hydrometry Guidelines for the application of acoustic velocity meters using the Doppler and echo corr
23、elation methods 1 Scope This International Standard provides guidelines on the principles of operation and the selection and use of Doppler-based and echo correlation velocity meters for continuous-flow gauging. This International Standard is applicable to channel flow determination in open channels
24、 and partially filled pipes using one or more meters located at fixed points in the cross-section. NOTE A limitation of the techniques is that measurement is made of the velocity of particles, other reflectors or disturbances. 2 Normative references The following referenced documents are indispensab
25、le for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document applies. ISO/TS 25377:2007, Hydrometric uncertainty guidance (HUG) ISO 772, Hydrometry Vocabulary and symbols 3 Terms, definitions and
26、abbreviated terms 3.1 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 772 and the following apply. 3.1.1 beam angle mounting angle of the acoustic transducer relative to the normalized profiling direction NOTE Different beam angles will be suitable for
27、 different applications. 3.1.2 beam width width of the acoustic signal transmitted, in degrees (), from the centre of the transducer NOTE This, coupled with the side lobe of the acoustic signal, will affect the suitability of a particular instrument for its application, based on the mounting locatio
28、n and the distance of the water volume measured from the sensor. BS ISO 15769:2010ISO 15769:2010(E) 2 ISO 2010 All rights reserved3.1.3 bed-mounted device upward-looking Doppler or echo correlation device that measures velocities within a beam looking upwards at an angle through the water column 3.1
29、.4 bin depth cell portion of the water sampled by the instrument at a known distance and orientation from the transducers NOTE The instrument determines the velocity in each cell. 3.1.5 blanking distance portion of water close to the instrument that is not sampled by Doppler technology NOTE 1 This i
30、s left blank to allow the transducer to stop “ringing” before it receives reflected signals. NOTE 2 It is also used to avoid the instrument sampling velocity in the zone of flow interference created close to, and by, the instrument. 3.1.6 broad-band Doppler instrument that records velocity at set di
31、stances from the sensor (see range-gated Doppler, 3.1.11) using coded acoustic pulses to make multiple velocity measurements from a single pulse pair (ping) 3.1.7 continuous Doppler simple type of Doppler instrument that measures the Doppler shift of all the particles within the range of the beam, t
32、aking the frequency with the largest peak as the average 3.1.8 downward-looking device instrument that can be deployed floating on the water surface looking down into the water column 3.1.9 echo (cross) correlation acoustic technique for recognizing echo images that can be used to determine the velo
33、city of particles moving in the flowing water 3.1.10 profiling Doppler Doppler instrument that discriminates between signals from reflectors at different distances from the sensor and uses this information to moderate the estimate of average velocity 3.1.11 range-gated Doppler sophisticated Doppler
34、instrument that records particle velocities at pre-set distances from the sensor NOTE Some instruments can produce velocity profiles along the length of the beam, while others just log measurements from one or more pre-defined cells. 3.1.12 side lobe most transducers that are developed using current
35、 technology have parasitic side lobes that are emitted off the main acoustic beam NOTE The side-lobe effect needs to be allowed for in the design and operation of the instrument. BS ISO 15769:2010ISO 15769:2010(E) ISO 2010 All rights reserved 33.1.13 side-looker Doppler usually mounted on the side o
36、f the channel 3.1.14 stage water level measured relative to a fixed datum EXAMPLE The level of the lowest point in the channel. 3.1.15 upward-looking device bed-mounted instrument that looks up through the water column 3.2 Abbreviated terms Abbreviation Meaning Notes ADCP acoustic Doppler current pr
37、ofiler ADP acoustic Doppler profiler This is a registered trademark of Sontek/YSI.1)ADVM instrument acoustic Doppler velocity meter Term used to describe a profiling acoustic Doppler velocity. ADVP H-ADCP acoustic Doppler velocity profiler horizontal ADCP Alternative acronym and name for ADCP. Side/
38、bank-mounted acoustic Doppler velocity profiler. H-ADVM horizontal ADVM Side/bank-mounted acoustic Doppler velocity meter. 4 Principles of operation of the techniques 4.1 Ultrasonic Doppler The method of velocity measurement used is based upon a phenomenon first identified by Christian Doppler in 18
39、43. The principle of “Doppler shift” describes the difference, or shift, which occurs in the frequency of emitted sound waves as they are reflected back from a moving body. The sensors of Doppler systems normally contain a transmitting and a receiving device (see Figure 1). A sound wave of high freq
40、uency (Fs) is transmitted into the flow of water and intercepted and reflected back at a different frequency by tiny particles or air bubbles (reflectors). A typical reflector n produces a frequency shift Fdn. The “shift” between transmitted and reflected frequencies is proportional to the movement
41、of particles relative to the position of the sound source (i.e. the sensor). 1) Sontek/YSI is an example of a suitable product available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of this product. BS ISO 15769:2
42、010ISO 15769:2010(E) 4 ISO 2010 All rights reservedKey 1 Doppler sensor 2 water surface 3 channel bed a, b and c particulates Fsfrequency of transmitted sound pulse Fa, Fband Fcfrequency of sound pulses reflected from particulates a, b and c Va, Vband Vcvelocity of particulates a, b and c . angle be
43、tween the horizontal and the angle of the sound beam Figure 1 Principle of Doppler ultrasonic flow measurement Doppler shift only occurs if there is relative movement between the transmitted sound source and the reflected sound source along the acoustic beam (but not if it is perpendicular to it). T
44、he velocity of the moving reflector n can be calculated from a) the magnitude of the Doppler shift, b) the angle between the transmitted beam and the direction of movement, and c) the velocity of sound in water. It can be shown that vn= Fdn c/2Fscos .nwhere Fdnis the Doppler frequency shift produced
45、 by reflector n; Fsis the frequency of sound with no movement; vnis the relative velocity between the transmitted sound source and reflector n; c is the velocity of sound in water; .nis the angle between the reflectors line of motion (the assumed flow path) and the direction of the acoustic beam. BS
46、 ISO 15769:2010ISO 15769:2010(E) ISO 2010 All rights reserved 5A Doppler velocity meter measures the resultant frequency shift produced by a large number of reflectors, of which reflector n is typical, and from that computes a mean velocity. It is the velocity of moving particles, and not water velo
47、city, which is measured. By including the velocity of many particles, it aims to make an estimate of the mean water velocity of the volume sampled by the acoustic beam. Although the particles, if small, will travel at almost the same speed as the water, sampling errors may occur depending on the spa
48、tial and velocity distribution of the particles. The cross-sectional area is also required to apply the velocity-area calculation of discharge. Most systems incorporate a water-level sensor, and combining the water depth with knowledge of the cross-sectional profile allows the flow to be calculated.
49、 4.2 Operating techniques 4.2.1 Introduction All Dopplers fit into one of four general categories, based upon the method by which the measurements are made: a) continuous wave Dopplers; b) pulsed incoherent profiling Dopplers (including narrow band); c) pulse-to-pulse coherent; d) spread spectrum or broad band. The last three of these four categories are all range gated. Range gating breaks the signal into successive segments and processes each segment independently of the others. This allows the instrument to measure the profi
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