1、Designation: D 5737 95 (Reapproved 2006)Standard Guide forMethods for Measuring Well Discharge1This standard is issued under the fixed designation D 5737; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、 number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers an overview of methods to measurewell discharge. This guide is an integral part of a series ofstandards prepared on
3、 the in-situ determination of hydraulicproperties of aquifer systems by single- or multiple-well tests.Measurement of well discharge is a common requirement tothe determination of aquifer and well hydraulic properties.1.2 This guide does not establish a fixed procedure for anymethod described. Rathe
4、r, it describes different methods formeasuring discharge from a pumping or flowing well. Apumping well is one type of control well. A control well canalso be an injection well or a well in which slug tests areconducted.1.3 This guide does not address borehole flow meters thatare designed for measuri
5、ng vertical or horizontal flow within aborehole.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibili
6、ty of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Furthermore, it isthe users responsibility to properly dispose of water dis-charged.1.6 This guide offers an organized collection of informat
7、ionor a series of options and does not recommend a specificcourse of action. This document cannot replace education orexperience and should be used in conjunction with professionaljudgment. Not all aspects of this guide may be applicable in allcircumstances. This ASTM standard is not intended to rep
8、re-sent or replace the standard of care by which the adequacy ofa given professional service must be judged, nor should thisdocument be applied without consideration of a projects manyunique aspects. The word “Standard” in the title of thisdocument means only that the document has been approvedthrou
9、gh the ASTM consensus process.2. Referenced Documents2.1 ASTM Standards:2D 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 1941 Test Method for Open Channel Flow Measurementof Water with the Parshall FlumeD 4043 Guide for Selection of Aquifer Test Method inDetermining Hydraulic Properti
10、es by Well TechniquesD 5242 Test Method for Open-Channel Flow Measurementof Water with Thin-Plate WeirsD 5390 Test Method for Open-Channel Flow Measurementof Water with Palmer-Bowlus FlumesD 5716 Test Method for Measuring the Rate of Well Dis-charge by Circular Orifice Weir2.2 ISO Standard:Recommend
11、ation R541 Measurement of Fluid Flow byMeans of Orifice Plates and Nozzles32.3 ANSI Standard:Standard 1042 Part 1 Methods for the Measurement of FluidFlow in Pipes, 1, Orifice Plates, Nozzles and VenturiTubes32.4 ASME Standard:Standard MFC-3M-1989 Measurement of Fluid Flow inPipes Using Orifice, Noz
12、zle, and Venturi43. Terminology3.1 Definitions:3.1.1 conceptual modelan interpretation or description ofthe characteristics, interactions, and dynamics of a physicalsystem.3.1.2 control wella well by which the head and flow in theaquifer is changed, by pumping, injection, or imposing achange of head
13、.3.1.3 dischargeor rate of flow, is the volume of water thatpasses a particular reference section in a unit of time.1This guide is under the jurisdiction ofASTM Committee D18 on Soil and Rockand is the direct responsibility of Subcommittee D18.21 on Ground Water andVadose Zone Investigations.Current
14、 edition approved July 1, 2006. Published August 2006. Originallyapproved in 1995. Last previous edition approved in 2000 as D 5737 95 (2000).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards vol
15、ume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute, 11 W. 42nd St., 13thFloor, New York, NY 10036.4Available from American Society of Mechanical Engineers, 345 E. 47th Street,New York, NY 10017.1Copyright ASTM Intern
16、ational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.4 totalizing flow metera flow meter that indicates thecumulative flow displayed as a volume. The flow rate iscalculated based on the time between two readings.3.2 For definitions of other terms used in t
17、his guide, seeTerminology D 653.4. Significance and Use4.1 This guide is limited to the description of test methodstypical for measurement of ground-water discharge from acontrol well.4.1.1 Controlled field tests are the primary means of deter-mining aquifer properties. Most mathematical equations d
18、evel-oped for analyzing field tests require measurement of controlwell discharge.4.1.2 Discharge may be needed for evaluation of welldesign and efficiency.4.1.3 For aquifer tests, a conceptual model should beprepared to evaluate the proper test method and physical testrequirements, such as well plac
19、ement and design (see GuideD 4043). Review the site data for consistency with the concep-tual model. Revise the conceptual model as appropriate andconsider the implications on the planned activities.4.1.4 For aquifer tests, the discharge rate should be suffi-cient to cause significant stress of the
20、aquifer without violatingtest assumptions. Conditions that may violate test assumptionsinclude conversion of the aquifer from confined to unconfinedconditions, lowering the water level in the control well tobelow the top of the well screen, causing a well screen entrancevelocity that promotes well d
21、evelopment during the test, ordecreasing the filter pack permeability characteristics.4.1.5 Some test methods described here are not applicable toinjection well tests.4.2 This guide does not apply to test methods used inmeasurement of flow of other fluids used in industrial opera-tions, such as wast
22、e water, sludge, oil, and chemicals.5. Test Methods5.1 Selection of a Well Discharge Rate MeasurementMethodSelect a well discharge measurement method basedon the desired discharge rate or rates, the desired pumpingmethod, the required accuracy and frequency of measurement,the type of pump discharge
23、and the water conveyance method.5.2 Principal Well Discharge Rate MeasurementMethodsA summary of principal methods is given below fortypical hydrogeologic testing. Additional information may befound in a publication of the National Institute of Standardsand Technology (NIST) (1),5the American Societ
24、y of Me-chanical Engineers (ASME) (2), or in a comprehensive bookon the subject of flow meter engineering (3). Dischargemethods can be classified as open channel flow and closedconduit flow. Open channel flow is limited to calibrated controlstructures, such as weirs and flumes. Closed conduit flowin
25、cludes methods such as turbine meters and magnetic meters.Also included are methods that measure the discharge of waterfrom the closed conduit to the air, such as the orifice tube.5.3 Open Channel Flow Methods:5.3.1 WeirsA weir is a vertical obstruction that restrictsthe total flow of water in chann
26、el. Weirs fall into three generalclassifications, sharp crested, broad crested, and suppressed.Sharp crested weirs use a flat plate that is configured in atriangular “V” or rectangular shape; they are described in5.3.1.1. See Test Method D 5242. Broad crested weirs are widerectangular restrictions t
27、hat are usually only used as spillwaysin dams. They are not described here. More information onbroad crested weirs may be found in Ref (4). A third classifi-cation of weirs, called suppressed weirs, are more commonlyknown as flumes. Flumes are discussed in 5.3.2.5.3.1.1 Sharp Crested WeirsThe weir i
28、s placed flushagainst the flowing stream, and the notch is made as sharp aspossible using a flat piece of metal with sharp edges formingthe weir notch. The relation between the head and the dischargeof a weir varies according to the shape of the weir notch. Aweir is inexpensive to construct, easy to
29、 install and highlyaccurate when installed and used properly.5.3.2 FlumeA flume is a device that restricts flow in thechannel which causes the water to accelerate, producing acorresponding change in the water level. The head can then berelated to discharge. Several types of flumes have beendeveloped
30、; the most common flume for measuring well dis-charge is the Parshall flume, originally designed by R. L.Parshall of the U.S. Soil Conservation Service (5). See TestMethods D 1941 and D 5390.5.3.2.1 Flumes have several advantages over weirs. Themost important of these is the self-cleaning capacity o
31、f flumescompared with sharp-edged weirs. Head losses through a flumeare also much less than for a weir, so when the available headis limited, flumes are more desirable. Flumes can function overa wide range of discharges and still require only a singleupstream head measurement. However, flumes requir
32、e moretime to set up than weirs.5.4 Closed Conduit Methods:5.4.1 Invasive Methods:5.4.1.1 Turbine-Type (Propeller) Flow MetersAtotalizingflow meter is a device used in measuring water in mostdomestic and commercial potable water uses. This flow meterconsists of a flow tube in which a rotor blade is
33、mountedtogether with either a means of generating an electrical signalproportional to the angular velocity of the rotor or a mechanicalsystem of gears that rotates proportional to the flow volume.The meter is installed as a section of the water line between thepump and the point of discharge. Turbin
34、e-type flow metershave a limited operating range. The meter must be calibratedand the pipe must be full. Mechanical turbine meters typicallyonly totalize flow.5.4.2 Noninvasive Methods:5.4.2.1 Magnetic Flow MetersThe magnetic flow meteroperates on the same general principle as an electric generator(
35、2). The pipe is placed such that the fluid path is normal to themagnetic field. The motion of the fluid through the magneticfield induces an electromotive force across the fluid. Byplacing insulated electrodes in the pipe in a plane normal to themagnetic field the strength of the field can be measur
36、ed usinga special voltmeter. An electromotive force is induced in the5The boldface numbers given in parentheses refer to a list of references at theend of the text.D 5737 95 (2006)2flowing water (that is, the conductor) across a pair of elec-trodes. Advantages are that there is no added head loss.Di
37、sadvantages include their relatively high cost and potentialerrors due to scaling.5.4.2.2 Venturi MetersThe venturi meter uses the relation-ship between pressure and flow velocity across a throat.Advantages include less head loss relative to orifice meters andless required maintenance. More informat
38、ion may be gainedfrom British Standard 1042.5.4.2.3 Acoustic MetersThe acoustic meter, also calledthe sonic meter or doppler flow meter, uses sound waves inconjunction with knowledge of pipe wall thickness to allowestimation of flow rate. Many acoustic meters require sus-pended material or entrapped
39、 air to obtain a quality reading.Anadvantage of acoustic meters over other types is their limitedmechanical parts and thus longer equipment life. A disadvan-tage is sensitivity to pipe encrustation.5.4.3 Discharge to Air Methods:5.4.3.1 Bucket and Stop WatchThe bucket and stop watchmethod is simply
40、the collection of discharged water in acontainer of known volume for a measured period of time. Thevolume collected divided by the time the water is collected isthe discharge rate over that time period. Alternately, thevolume can be determined by measuring the weight and usinga density conversion. T
41、he rate is measured periodically overthe course of the test. Advantages include its ease to set up andthe simplicity of taking readings. Disadvantages include itsmanual operation and inability to obtain continuous measure-ments.5.4.3.2 Orifice BucketThe orifice bucket is a containerwith precisely cu
42、t holes in the bottom and a calibratedpiezometer tube on the side. The well discharge is directed intothe top of the bucket where water then accumulates as it isdelayed in flowing out the holes located in the base of thecontainer. The accumulated head can be read on the piezometertube. The discharge
43、 is read from a chart relating discharge tohead. The device is especially useful in measuring rates ofproduction of reciprocating and airlift pumps where the flow isnot at a uniform rate. An orifice bucket 30.5 cm (12 in.) indiameter can be constructed to measure discharge rates from 8to 151 L/min (
44、2 to 40 gal/min). An orifice bucket 61.0 cm (24in.) in diameter can be constructed to measure discharge ratesfrom 38 to 680 L/min (10 to 180 gal/min). Advantages includeits ease in setup and use and its ability to be configured with afloat water level recorder. The orifice bucket was described bythe
45、 Illinois State Water Survey (5).5.4.3.3 Circular Orifice WeirAlso called the orifice tubeand orifice meter, the circular orifice weir is the device oftenused to measure the discharge rate from a high-capacity pump.The orifice meter is a circular restriction in a pipe that causesback pressure that c
46、an be measured in a piezometer tube. Thewater level in the piezometer tube is the pressure head in theapproach pipe when water is being pumped through the orifice.For any size of orifice diameter and approach pipe diameter,the rate of flow through the orifice varies with the pressurehead in the piez
47、ometer tube. For example, a discharge of208 L/min (55 gal/min) will cause 12.7 cm (5 in.) of head dueto a 6.35-cm (212-in.) orifice and a 10.16-cm (4-in.) approachpipe. Similarly, a discharge of 20 100 L/min (5 310 gal/min)will cause 177.8 cm (70 in.) of head due to a 30.48-cm (12-in.)orifice and a
48、40.64 cm (16-in.) approach pipe. Advantages arethe low cost and relatively high accuracy of measurement.Disadvantages include the relatively low range of measure-ment, high head loss, and physical constraints, for example, theorifice meter must be level and must always run full. For moreinformation
49、see ISO Recommendation R541 and Layne West-ern Company, Inc. (6) and Test Method D 5716.5.4.3.4 Trajectory MethodThe flow rate can be deter-mined from measurement of the trajectory of a horizontal pipedischarge to the air. Curves were prepared from PurdueUniversity experiments in 1948 on pipes from 5.08 to 15.24 cm(2 to 6 in.) in diameter (1). Tabularized data also exist fordischarge from vertical pipes.5.5 Procedures Specific to Measurement of Well Dischargefor Aquifer Test Analysis:5.5.1 Certain aquifer tests require variation of the dischargerate over the cours
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