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1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS ISO 14139:2000 ICS 17.
2、120.20 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Hydrometric determinations Flow measurements in open channels using structures Compound gauging structures Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 04:14:08 GMT+00:00 2006, Uncontrolled Copy, (c) BSI This Bri
3、tish Standard, having been prepared under the direction of the Sector Committee for Materials and Chemicals, was published under the authority of the Standards Committee and comes into effect on 15 August 2000 BSI 08-2000 ISBN 0 580 36074 1 BS ISO 14139:2000 Amendments issued since publication Amd.
4、No.DateComments National foreword This British Standard reproduces verbatim ISO 14139:2000 and implements it as the UK national standard. It supersedes BS 3680-4D:1989 which is withdrawn. The UK participation in its preparation was entrusted by Technical Committee CP/113, Hydrometry, to Subcommittee
5、 CPI/113/2, Notches, weirs and flumes, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international an
6、d European developments and promulgate them in the UK. This standard states that it is mandatory to include divide piers between adjacent sections of compound gauging structures. This recommendation was originally made because of a lack of information on the performance of structures without divide
7、piers. Research has now been carried out on structures without divide piers and this research has shown that gross errors can arise if divide piers are omitted, thus confirming the original recommendation. A list of organizations represented on this subcommittee can be obtained on request to its sec
8、retary. Cross-references The British Standards which implement international publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled International Standards Correspondence Index, or by using the Find facility of the BSI Standards Electronic Ca
9、talogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document c
10、omprises a front cover, an inside front cover, the ISO title page, pages ii to iv, pages 1 to 41 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 04:14:08 GMT+00:00 2006, Uncontro
11、lled Copy, (c) BSI Reference number ISO 14139:2000(E) INTERNATIONAL STANDARD ISO 14139 First edition 2000-06-15 Hydrometric determinations Flow measurements in open channels using structures Compound gauging structures Dterminations hydromtriques Mesure de dbit des liquides dans les canaux dcouverts
12、 au moyen de structures Structures de jaugeage hybrides Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 04:14:08 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 14139:2000(E) ii Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 04:14:08 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 14139
13、:2000(E) iii Contents Page Foreword.iv 1 Scope 1 2 Normative references1 3 Terms, definitions and symbols.2 4 Characteristics of compound gauging structures.3 5 Installation4 5.1 Selection of site .4 5.2 Installation conditions.5 6 Maintenance.6 7 Measurement of head7 7.1 General7 7.2 Stilling well.
14、7 7.3 Zero setting 8 7.4 Location of head measurement section(s) .8 8 Computation of discharge 8 8.1 Modular flow conditions .8 8.2 Non-modular (drowned) flow conditions 9 9 Errors in flow measurement.9 9.1 General9 9.2 Sources of error.9 9.3 Kinds of error.9 9.4 Errors in coefficient values and err
15、ors in measurement.10 9.5 Combinations of uncertainties to give overall uncertainty in total discharge10 9.6 Presentation of results11 Annex A (normative) Velocity distribution .12 Annex B (normative) Non-modular (drowned) flow.14 Annex C (normative) Methods of calculations.24 Licensed Copy: sheffie
16、ldun sheffieldun, na, Sun Nov 26 04:14:08 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 14139:2000(E) iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is nor
17、mally 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 ISO, also take part in
18、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 3. Draft International Standards adopted by the techn
19、ical 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 possibility that some of the elements of this International Standard may be the subject of patent
20、 rights. ISO shall not be held responsible for identifying any or all such patent rights. International Standard ISO 14139 was prepared by Technical Committee ISO/TC 113, Hydrometric determinations, Subcommittee SC 2, Notches, weirs and flumes. Annexes A to C form a normative part of this Internatio
21、nal Standard. Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 04:14:08 GMT+00:00 2006, Uncontrolled Copy, (c) BSI INTERNATIONAL STANDARD ISO 14139:2000(E) 1 Hydrometric determinations Flow measurements in open channels using structures Compound gauging structures 1 Scope This International St
22、andard specifies the methods of measurement of flow in rivers and artificial channels, using any combination of standard weirs and/or flumes in a compound structure. For guidance on the selection of weirs and/or flumes, refer to ISO 8368. All structures can be operated in the modular flow range, but
23、 only a limited number of structures can be used in the drowned (non-modular) flow range (see clause 4). Compound weirs improve the quality of discharge measurements at low stages. The characteristics of velocity distribution are described annex A. Structures standardized for operation in the drowne
24、d (non-modular) flow range and the method of computation of flow are described in annex B. Methods and examples of flow measurement calculations are given in annex C. Compound flow-measuring structures without divide piers need in situ or model calibrations and are not covered by this International
25、Standard. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties
26、 to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain
27、 registers of currently valid International Standards. ISO 772:1996, Hydrometric determinations Vocabulary and symbols. ISO 1438-1:1980, Water flow measurement in open channels using weirs and Venturi flumes Part 1: Thin-plate weirs. ISO 3846:1989, Liquid flow measurement in open channels by weirs a
28、nd flumes Rectangular broad-crested weirs. ISO 4359:1983, Liquid flow measurement in open channels Rectangular, trapezoidal and U-shaped flumes. ISO 4360:1984, Liquid flow measurement in open channels by weirs and flumes Triangular profile weirs. ISO 4362:1999,Hydrometricdeterminations Flowmeasureme
29、ntinopenchannelsusingstructures Trapezoidal broad-crested weirs. ISO 4374:1990, Liquid flow measurement in open channels Round-nose horizontal broad-crested weirs. ISO 4377:1990, Liquid flow measurement in open channels Flat-V weirs. Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 04:14:08 GM
30、T+00:00 2006, Uncontrolled Copy, (c) BSI ISO 14139:2000(E) 2 ISO/TR 5168:1998, Measurement of fluid flow Evaluation of uncertainties. ISO 8333:1985, Liquid flow measurement in open channels by weirs and flumes V-shaped broad-crested weirs. ISO 8368:1999,Hydrometricdeterminations Flowmeasurementsinop
31、enchannelsusingstructures Guidelines for selection of structure. ISO 9826:1992, Measurement of liquid flow in open channels Parshall and SANIIRI flumes. ISO 9827:1994, Measurement of liquid flow in open channels by weirs and flumes Streamlined triangular profile weirs. 3 Terms, definitions and symbo
32、ls For the purposes of this International Standard, the terms and definitions given in ISO 772 apply. A full list of symbols with the corresponding units of measurement is given below. Symbol Units of measurement A area of cross-section of flow m2 b crest width m B width of approach channel m CDcoef
33、ficient of discharge non-dimensional Cdrdrowned-flow reduction factor non-dimensional Cvcoefficient of approach velocity non-dimensional e uncertainty in absolute magnitude non-dimensional g acceleration due to gravity m/s2 h gauged head m H total head m hpcrest-tapping pressure head m hvvelocity ap
34、proach head m L length of flume throat or weir crest in direction of flow m n number of measurements in a set non-dimensional p height of flume invert or weir crest above mean bed level m Q total discharge m3/s Q1, Q2, Q3individual section discharges (in general Qn)m3/s Qmodtotal modular discharge m
35、3/s q discharge per unit width m3/s systandard deviation of a set of measurements of quantity y m y s estimated standard deviation of the mean of several readings of quantityy m v mean velocity at cross-section m/s a v mean velocity in approach channel m/s XQpercentage uncertainty in total discharge
36、 non-dimensional Licensed Copy: sheffieldun sheffieldun, na, Sun Nov 26 04:14:08 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 14139:2000(E) 3 XQ,1, XQ,2, XQ,31)percentage uncertainty in individual section discharges non-dimensional Xtupercentage uncertainty in estimating upstream water levels or u
37、pstream total head levels non-dimensional Xtdpercentageuncertaintyinestimatingdownstreamwater levels or downstream total head levels non-dimensional Xypercentage uncertainty in quantity y non-dimensional ?Coriolis energy coefficient non-dimensional ?difference in weir-crest levels m ?boundary layer
38、displacement thickness m Suffixes 1 denotes upstream value 2 denotes downstream value Superscripts G refers to gauging section T refers to crest-tapping section S refers to any other section 4 Characteristics of compound gauging structures A compound gauging structure as covered by this Internationa
39、l Standard comprises two or more individual structures, operated in parallel and separated by divide piers. The individual structures, which can be used in a compound gauging weir, are specified in ISO 1438-1, ISO 3846, ISO 4359, ISO 4360, ISO 4362, ISO 4374, ISO 4377, ISO 8333, ISO 9826 and ISO 982
40、7. The structures described in ISO 4360, ISO 4362, ISO 4377, ISO 8333, ISO 9826 and ISO 9827 may be used in the drowned flow range (see annex B.1). In the modular flow range, discharges depend solely on upstream water levels, and a single measurement of upstream head is required. In the drowned flow
41、 range, discharges depend on both upstream and downstream water levels, and two independent head measurements are required. These are: a)the upstream head; and either b)the head measured in the crest-tapping for a triangular profile weir (two dimensional or flat-V forms); c)the head measured within
42、the throat of a Parshall flume; or d)the head measured in the tailwater for the other structures. 1)In cases where the subscript of a symbol also contains a subscript, it is house style to write the second subscript on the same line, after a comma. Thus 1 Q X is written XQ,1. Licensed Copy: sheffiel
43、dun sheffieldun, na, Sun Nov 26 04:14:08 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 14139:2000(E) 4 The flow conditions considered are limited to steady or slowly changing flows. The essentially parallel flow through the compound structure is ensured by the use of divide piers. The flow is separ
44、ated by the divide piers into each individual weir or flume. The discharge can be determined through each individual section by a single upstream head measurement, at one section only, in the case of modular flow or by two independent head measurements, at one section only, as required for drowned f
45、low conditions. The summation of the discharges through each of the sections provides the measurement of total flow within the channel. 5 Installation 5.1 Selection of site A preliminary survey shall be made of the physical and hydraulic features of the proposed site to check that it conforms (or ma
46、y be made to conform) to the requirements necessary for measurement using the weir. Particular attention shall be paid to the following features in selecting the site of the weir: a)the availability of an adequate length of channel of regular cross-section; b)the existing velocity distribution; c)th
47、e avoidance of channels having gradients greater than 0,4 %; d)the effects of any increased upstream water level due to the flow-measuring structure; e)the conditions downstream, including such influences as tides, confluence with other streams, sluice-gates, mill dams and other controlling features
48、 that might cause drowning; f) the impermeability of the ground on which the structure is to be founded, and the necessity for piling, grouting or other sealing in river installations; g)the necessity for flood banks to confine the maximum discharge to the channel; h)the stability of the banks, and
49、the necessity for trimming and/or revetment in natural channels; i) the clearance of rocks or boulders from the bed of the approach channel; j) the effects of wind. NOTE 1 Wind can have a considerable effect on the flow in a river or over a weir, especially if these latter are wide and the head is small and the prevailing wind is in a transverse direction. If the site does not possess the characteristics required for satisfactory measurements, it shall be rejected unless suitable improvements are practicable. If a survey of a str