© Armfield Ltd. 2012
NEW
Computer controlled research flumes available as standardLaboratory FLumes and ChanneLs For hydrauLiC teaChing/researCh studies
s series: aPPLied hydrauLiCs & hydroLogyWITH DISCOVER
FEaturiNg
> Standard Flumes > Special Flumes, Tanks and Basins > Ancillary Equipment
•SedimentTransportFacilities •MonoandRandomWaveMakers •Instrumentation
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SOFTWAREArmSoft™
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issue 2The latest version of this data sheet is available at:
www.armfield.co.uk/flumes
Crump weir
Armfield has been designing and supplying openchannelfacilities(sometimesreferredtoasflumes)tohydrauliclaboratoriesthroughouttheworldforover50years.
Thisbrochurepresentsthefullrangeofchannels/flumesavailablefromArmfield,bothteaching&research,Standard&special.
Therearealsogeneralcommentsaboutthedesign,flexibility&accuracyofflumesinordertoassistthoseembarkingonthespecifying&purchaseofflumesforadvancedstudiesorresearch.
Usuallychannelsareofrectangularprismaticsection.Thedimensionsoftheworkingcross-sectionandlengtharetheprincipal
featureswhichdetermineboththefunctionalsuitabilityandthecostofachannel.
Dependingoncustomerrequirements,channelscanbedesignedtoincorporatethefollowingalternativefeatures:
•fixedbedorvariableslope
•self-containedorlaboratorysuppliedwater
•opencircuitorre-circulatingsedimentload
•choiceofworkingsectionmaterials(glass,metal,wood)
•inclusionofawavegeneratorandbeach
•instrumentationsystemsforflow,velocity,level,etc.
•sedimentsampling
iNtroduCtioN
10M Research Flume - Purdue University, USA
Becauseofthephysicalsizeandthegeneralheavynatureoftheconstruction,itiseasytoforgetthataflumeisaninstrumentandinmanyinstancesrequiredtohaveahighlevelofintegrityregardingbothitsworkingdimensionsandabilitytoachieverepeatableresults.
Armfieldacknowledgethenecessityforaccuracy,precisionandrepeatability.
Thesearecornerstonesofthedesign,manufactureandfinalinstallation.
diMENSioNS
Thecriticaldimensionsofaflumearetheworkinglengthandcross-section(widthanddepth).Workinglengthalsomeansusablelength.Alltoooftentheturbulententryconditionsrequireasubstantialportionofwhatwouldbedescribedastheworkingsectionbeforesuitableflowconditionsprevail.Armfieldflumesaredesignedsuchthattheworkinglengthismaximised.Theoveralldimensionsoftheflumearealsominimisedthroughcarefuldesignoftheinletandoutletconditionsandsensibleuseofthespaceunderneaththeflumeandimmediatelyadjacent.
thE KEy FEaturES oF aN opEN ChaNNEl FaCility
S6MkII flow channel complete with its own service system
Thematerialsofconstructionareofparamountimportance,notonlyforthedurabilityandlongevityrequiredofanexpensivepieceofequipment,butalsosuitabilityforpurpose.Manyflumesareusedforsedimenttransportstudiesandthereforethematerialsincontactwiththesedimentmusthaveabrasionresistance.InsuchinstancesitisstandardpracticeforArmfieldtoincorporatestainlesssteelonthebedofflumes.
Clarityofflowvisualisationisanessentialingredient,particularlyiflaserdoppleranemometryorsophisticatedphotographyisinvolved.Evenpotablewaterwillabradeasurfacebutwatercontainingharshparticles,suchassediment,willquicklydamageanysoftmaterial.ThisiswhyallArmfieldflumesareconstructedwithtoughenedglassviewingpanels,whetherthesebesmallportholesorfulllengthworkingsections.Toughenedglassisalsousedasasafetyfeature.Intheunlikelyeventthataglasspanelshatters,itwillnotbreakintodangeroussharpshardsbutintosmallrelativelyharmlesscubes.
Whereverpossiblethemorebasiccomponentsincontactwithwateraremadeofnon-corrodingmaterials,suchasplastic,GRP,orstainlesssteel.Pumpsareusuallycastironbutwheresedimentisinvolvedwerecommendtheuseofspecialpumps,typicallyglasslined.Wherewoodoracompositematerialischosenforthebaseand/orsidesoftheflume,thesearecarefullytreatedtoprotectagainstwateringress.
Armfieldflumes,whetherastandardproductorcustomised,arebuiltonamodularprinciple.Thisallowsthemtobedeliveredtositeinpre-fabricated,manageablesections.
Thedesignsaresuchthatinsomecaseswithhelpfromtheinstructionmanual,clientsareabletoassembleandcommissiontheequipmentwithouttheneedforourskilledstaff.Howeverthisisalwaysanoption,andArmfieldarehappytosubmitaquotationforinstallation,commissioningand,whereappropriate,basictraining.
EaSE oF uSE
Experimentationcanbeatime-consumingandtediousbusiness.Quiteoftenlongperiodsarerequiredinordertogathersufficientmeaningfuldata.Itisatthesetimesthattheuserappreciatesequipmentthathasbeencarefullydesignedfromanergonomicviewpoint.
Armfieldincorporatesmanyfeaturestoeasethelifeoftheoperator.Allcontrolsonasinglefloormountedconsole.Electricaloptionsfordrivingvalves,jackingsystemsandweirs.Directreadingflowmeterinstrumentation,withdigitalreadoutatthecontrolconsole.Poweredinstrumentcarriagesofferingthreewayaxes.Asensibleworkingheightthatprovidescomfortableaccesstotheworkingsection&computerlinkeddatagathering.
MatErialS oF CoNStruCtioN SEt-up aNd aSSEMbly
Typical control console S6MkII model mounting system
uNiForM FloW
Withinthelimitedconfinesofalaboratoryflumeitiscriticalthatthebestpossibleworkingconditionsareachievedasquicklyaspossibleaftertheflowenterstheworkingsection.Muchhingesontheentryconditionsandparticularlythemeansusedtosettleanddirecttheflowasitenterstheinlettankandisre-directedintotheworkingsection.
iNlEt taNK dESigN
TheinlettankdesigngenerallyadoptedasstandardbyArmfieldistheconsequenceof50yearsofexperiencecoupledwithcomprehensivemodeltestwork.Theresultisacarefullyshapedtank,withprofilingtoboththesidewallsandbase,whilstremainingcompactinitslength,anessentialingredienttominimisethewasteoflaboratoryspace.Withinthetankvariousstillingdevicesareincorporated.
lEvEl CoNtrol - thE outlEt WEir
Ofequalimportanceisthemethodofcontrollingthelevelwithintheflume.Thisisusuallydonethroughaweiratthedischargeend. ManyoptionsexistbutmostfrequentlyArmfieldutiliseeitheranadjustableovershottiltingweiror,formorecomplexflowconditions,avenetianblindweirwitheitherverticalorhorizontalslats.
WatEr Supply
Traditionallyhydrauliclaboratorieswereconstructedwithunderfloorsumpsandelevatedheadertankslinkedwitharingmain.Modernlaboratoriesrarelyenjoythesefacilities.
Armfieldare,however,abletosupplyflumeseitherinanonself-containedconfiguration,wheretheycanbeservicedfromanexistingheadertankanddischargetoalaboratorysump,orasfullyself-containedfacilities,wherefloormountedreservoirs,pumps,pipework,valvesandflowmetersareincorporated,including,whereappropriate,re-circulatingloopsforsedimenttransport.
hydrauliCS: pErForMaNCE aNd SyStEMS dESigN
S6MkII - Upstream of the Trapezoidal plate weir
Manyareasofstudyrequireorareenhancedbyusingflumeswithatiltingcapability.Thismostlytranslatesintopositiveslopebutsometimesthereistherequirementfornegativeslope.
Themostimportantaspectofatiltingflumeisretainingtheintegrityoftheworkingsection,i.e.,maintainingtolerances.
Toachievethisrequiresanextremelyrigiddesignwhichensuresalmostnodeflectionregardlessofloadortilt.Designofthejackingsystemiscrucialinguaranteeingthis.
Tiltingflumesneedjackstoraiseandlowerthem.Theneedforstabilityandthesizeandweightoftheinstallationmakethiselementofcrucialimportance.
Variousoptionsareavailable,includingchaindriveandhydrauliclift.None,however,givethedegreeofrepeatableaccuracyachievablewithscrewjacksdriventhroughshaftingandgearboxes.TheArmfieldchoice.
Longflumesneedaseriesofjackstationscarefullylinkedtoavoiddistortionofthemainframe.
Onlargerflumes,orwhereexceptionaldegreesofslopeareinvolved,apivotmechanismateachstationensuresaverticalaspecttothejacksatalltimes.
Otherfeaturesincludeindicatorsforsettingslope,soft“bearings”tolimitnoise,electricdrives(optional)anddetectionsystemspermittingoperationonlyifalljacksmovetogether.
tiltiNg FluMES JaCKiNg SyStEMS
Gearboxes at each jacking point ensures accuracy of the tilting channel bed and the benefits of ease of operation.
Detail of slope scale, and slope control Inch buttons with Emergency Stop. Electronic slope also indicated on the main control console - inset
S6MkII Jacking station
Notallapplicationsrequireaflumetobetilting.Inmanycasesitissufficientfortheunittohaveafixedhorizontalposition.Insuchcasestheoptionsforconstructionareincreased.Themostflexiblearrangementbeingawood/compositeandglasspanelledknock-downform.
Wood/CoMpoSitE aNd glaSS paNEllEd CoNStruCtioN
Flumesofthistypeareinvariablyfixedbed,asthestructuredoesnotlenditselftotherigidityrequiredfortiltingexceptinflumeswithasmallercrosssection.Theknock-downformatisparticularlysuitedforresearchfacilitieswherefutureprojectsmayrequireflowchannelsofdifferentproportions.
Theknock-downdesignprovidesforoptimumflexibilityintheassemblyoftheflume,inletandoutlettanks,servicepumpsandpipework.Thewallsaremadeofvarnishedplywoodorcompositematerialssometimesfacedwithstainlesssteelandglasspanelswhichareinterchangeable.Aspecialjointingcompound,whichremainsplastic,iswatertightandbondsitselftotheglassorwood/composite,sealsthepanelswhicharethemselvessupportedbymildsteelchannelsections.Thesesectionsarespacedatregularintervalsandsupporttheflumebedandsidewallsthroughadjustablejackingstuds.Itisthereforepossibletolevelandaligntheflumewiththeutmostaccuracy.
FixEd bEd FluMES, WavE taNKS aNd baSiNS
rECirCulatiNg SEdiMENt SyStEMS
Frequentlyinexperimentationthereistheneedforerosionand/ordeposition.Thisrequiresthecirculationofsediment.Forthisconfigurationaflowchannelrequiresarecirculatingloopenablingthewatercontainingsedimentinsuspensiontoberecirculated.Armfieldflowchannelscanbedesignedtoincorporatesuchloops,thepipeworkbeingdesignedtoensurethesedimentstaysinsuspensionanddoesnotsettleoutwithinthesystem.
Sedimentisabrasiveandthismakestheselectionofmaterialsofparticularimportance.Pumpsareusuallylinedwithglass,valvesarereducedtoaminimumandflowmeteringisviaelectro-magneticflowmetersthatdonotrequireanycomponentswithintheflow.Flowvisualisationareasmustbeoftoughenedglassandstainlesssteelisessentialonthebaseandintanks.
Studiesinvolvingbedmovementareincreasinglyrelevant,frequentlybasedaroundenvironmentalissues.Atopicnotoriouslydifficulttostudyinthefieldlendsitselftodetailedstudyusingaflowchannelinthecontrolledenvironmentofalaboratory.
NoN-rECirCulatiNg SyStEMS
Thesetendtobemorecomplexandrequirethatsedimentbecollectedafterdischarge,eitherthroughasettlingtankorhydro-cyclones.
aNCillary hardWarE
Thesetypicallyincludesedimentfeeders andsedimentsamplers.
Armfieldhavein-depthexperienceofalltheseoptionsandarehappytoadviseonsupply.
SEdiMENt traNSport
Exeter University - UK
Wavegenerationandtheeffectsofwavesaresignificantareasofstudy.Wavegeneratorsthemselvescanrangefromsimplemechanicalsystemsforregularwavesthroughmulti-paddlerandomgeneratingsystemsthatmaybecomputercontrolled.Formanyapplications,particularlycoastalmodelsandflumestudies,longcrestedanddirectionalrandomwavesaresufficienttomodeltheseastate.Foroffshorestudiesandsomeshallowwaterproblemsmulti-directionalcomponentsarerequired.
Influmesoropenchannels,suchasdescribedinthisbrochure,thereareanumberofdifferenttypesofwavemakerthatareappropriate.Forsmallscalelaboratoryinstallationselectricallydrivenpistonmachinesareavailable.Wherelargerflumesareinvolvedhydraulicpoweredpistonmachinesandfordeeperwater,wedgetypewavemakers.Flumesmaybeusedtostudybreakwaters,seawallsandbeachbehaviour,orforfundamentalresearch.
Multi-elementwavemakersrecreatecomplexshortcrestedwaves.Manywavemakersofthistypehavehinge-flaptypepaddlesandareused,forexample,inoffshoreseabasinswheremodelsofoilandgasrigsaretested.Forshallowwaterpistonmechanismisthepreferredmechanicaloption.
WhatevertheapplicationArmfieldcansupplyacompletesystemdesignedtosuityourparticularrequirements.
WavE gENEratorS
Associated British Ports - UK
Multi paddle, computer driven random wave maker
>Accurateforeducationandresearch
>Extremelystabledesign,nouseradjustmentsrequiredtotheflumebed
>Floorspacerequirementsreducedtoaminimum
>Fabricatedhighprecisionstainless steel channel bed
>Canbereadilyconvertedtoclosed-looprecirculationforsedimenttransportstudies
>Precisionscrewjacksprovideaccurateslopeadjustmentwithminimumeffort(poweredjacksavailableasanoption)
>Designedforeaseofvisibility:-toughenedglasssides;slimlinesidesupports;comfortableviewingheight.etc.
>Adjustableinstrumentrailswithpositioningscalesarefittedoverthewholeworkinglength
>Fullyprofiledinlettankfittedwithstillingandsmoothingdevices
>Dischargetankwithadjustableovershotweiranddrafttubetoavoidsplashingandreducenoise
>Modularconstruction-suppliedinpre-glazedsectionsforrapidandeasyassemblyonsite
>Wavegenerationoptions,bothregularandrandom-theendtanksactingasbasinsthusextendingtheworkinglength
>Standardflumeshaveacomprehensiverangeofaccessories,instrumentsandmodelsavailable
>Non-corroding,durablematerialsusedthrougoutforwatercontactingsurfaces
>Transversemembershavebeeneliminatedthroughouttheworkinglength
>Transparentsidesareoftoughenedglass,whichisextremelystrong,abrasionresistant,dimensionallystable,doesnotdiscolourorscratchandisinherentlysafe
>Workingsectionisfullyadjustable,enablingextremelyaccuratesetting
>Substantialunderframesreduceloaddeflectionstoaminimum
>Closetolerancesspecifiedandachieved
TherearenumerousdesignfeaturesassociatedwithArmfieldchannelfacilities,manyareunique. Thefollowinglistisnotexhaustive.Notallfeaturesareappropriatetoeverychannel.
MaJor dESigN FEaturES
Typical pump/pipework configuration
Detail showing side support and side wall adjustment system
F1-19 FloW ChaNNEl
ASimplechannelsuppliedasanaccessorytothepopulardemonstrationfacilityF1-10HydraulicsBench.Thechannelintroducesstudentstothecharacteristicsofflowinanopenchannelatanelementarylevel.
Formoreinformationseedata-sheet
URL: www.armfield.co.uk/f1
S16 hydrauliC FloW dEMoNStrator
Thisuniquefacilitydemonstratesflowthroughbothopenchannelsandclosedconduits.Ithasanelevatingbedsectionandmodelsofvarioushydraulicstructures.
Formoreinformation seedata-sheet
URL: www.armfield.co.uk/s16
tEaChiNg FluMES
F1-19
S16
C4MKii MultipurpoSE tEaChiNg FluME
ThisversatileteachingflumehasbeenspecificallydesignedtodemonstratetheprinciplesofFluidMechanicswhenappliedtoengineeringstructuresinopenchannelflow.Availablein2.5mor5.0mlengthsandwithawiderangeofaccessories.
Formoreinformationseedata-sheet URL: www.armfield.co.uk/c4
C4MkII shown with F1-10 Hydraulics Bench
LaserPIVSystemH41 forflowvisualisation (S16flumecompatible)
URL: www.armfield.co.uk/h41
S2 MobilE bEd aNd FloW viSualiSatioN taNK
Thisunitmaybeusedintwoprincipalfieldsofstudy.Thefirstinvolvesdetailedinvestigationofmobilebedsituations,Thesecond,twodimensionalflowvisualisation.
Formoreinformationseedata-sheet
URL: www.armfield.co.uk/s2
tEaChiNg FluMES -CoNtiNuEd
S8 shown with accessories and typical bed-form (Inset)
S8 SEdiMENt traNSport dEMoNStratioN ChaNNEl
Thisteachingfacilityallowsthedemonstrationofthefullrangeofbedformsthatariseinamobilebedastheflowand/orslopeareincreased.Theequipmentisportableandthereforemaybeusedintheclassroomaswellasinthelaboratory.
Formoreinformationseedata-sheet
URL: www.armfield.co.uk/s8
LaserPIVSystemH41 Forflowvisualisation (S8&S16flumecompatible)
URL: www.armfield.co.uk/h41
advaNCEd FloW ChaNNElS
Stilling device Flow profiler
Loughborough University flume during construction.
Armfieldofferadesign,manufactureandinstallationserviceforspecialchannelfacilitiesofalltypesandsizes.Theirreputationandexpertisehasdevelopedthroughtheevolutionofstandardproducts.Bythiswemeanhighqualityflumesofferedtoastandarddesign.
Historyandexperiencehasshownthatthereareanumberofoptimumcross-sectiondimensionsthatwillfillthegreatmajorityofeducationalandresearchneeds.
Armfieldnowofferarangeofstandardcrosssectionsinbothtilting&fixedbedconfiguration.
Theseare:
300mmwidex450mmdeep(S6MkII)Tiltingonly 600mmwidex600mmdeep(S20&S21) 1000mmwidex1000mmdeep(S22&S23)
Thelengthofaflumeisdictatedbymanyfactors.Commonamongstthemareexperimentalrequirements,spaceavailabilityandcost.StandardArmfieldflumesarethereforeavailableasmodularunitsrangingfrom5Mto15Minincrementsof2.5M
S6 MK ii glaSS SidEd tiltiNg FluMES
dESCriptioN
Iftherequirementisforaflumesuitablebothforteaching&project/researchworkthentheverypopularS6MkIIhastobetheflumeofchoice,offeringhighlevelsofdimensionalaccuracy,awideselectionofmodels&accessories&formattinginvariousconfigurations.
Aglasssidedtiltingflumewithfabricatedallstainlesssteelbed.Aworkingcross-sectionof300mmwideby450mmdeepandavailableinstandardworkinglengthsof5m,7.5m,10m,&15m.Longerlengthsareavailabletospecialorderinincrementsof2.5m.
Completelyself-containedandcomprisingtheworkingsection,mouldedinletanddischargetanks,aseriesofsumptanks,apump,anelectronicflowmeter,ajackingsystemandacontrolconsole.
Thechannelsectionisfullyglazedwithlargeclearpanelsoftoughenedglass.Thisiscoupled withcarefuldesignofthesidesupportprofilestoprovideexcellentvisibilityandallowflowvisualisationofthefullworkingheightoftheflume. The glass panels are sealed using a rubber “U”sectioncompressedbyanaluminiumalloyclampingstrip.Theflumebedismanufacturedtohightolerancesanddesignedwithanintegralwebsupportframetogivetheflumeahighdegreeofrigidityandstability.Rigiddowelledjointsareusedtoconnectthesections.Theoverallstrengthandrigidityofthedesignallowsexcellentstabilityfigurestobeachievedandeliminatestheneedtoprovideadjustingscrewsortoperformperiodicsettingupoftheflume
tomaintainitsspecification.Nounderframeorsupportstructureotherthanjacksisnecessary.
Instrumentrailsareprovidedalongtheentireworkinglengthoftheflumeandacontinuousscalecalibratedinmillimetresisprovidedalongthelengthofoneoftherails.Adjustablescrewsallowthetracktobesetlevelandtrue.
Excellentvelocityprofilesareachievedintheworkingsectionbycarefulshapingoftheinlettankandbytheincorporationofstillingandsmoothingdevices.Operatingwaterlevelsaremaintainedbyanovershottiltingweirlocatedinthedischargetank.Bothendtanksaremadefromtoughnon-corrodingGRP.
Watercirculationisbyacentrifugalpumpmountedbeneaththeflumechannel,drawingwaterfromaseriesofinterconnectednon-corrodingsumptanksmountedonthefloorandrunningalongsidetheflowchannel.Allinterconnectingpipesandfittingsaremadeofnon-corrodingmaterials.
Theflowisregulatedusingamanuallyadjustedvalve.Flowrateismeasuredusinganelectro-magneticflowmeteranddisplayedonadigitalreadoutlocatedonthecontrolconsole.
Thecontrolconsoleismountedonapedestalandlocatedinaconvenientpositionfortheinstallation,suchthatitiseasilyaccessibleandtheflowratecanbereadwhilstadjustingthevalve.Alsolocatedontheconsoletheemergencystopbuttonandthepumpcontrols.Anadditionalemergencystopbuttonisprovidedonlongerflumes.
Acomputercontrolanddataloggingpackageisalsoavailable.SeeS6MkII-50&S6MkII-90.
10m working section. The end tanks actually extend the effective length of the flow channel beyond this. S6 MkII Glass sided Tilting Flume
advaNCEd FloW ChaNNElS
Theflumeistiltedusingajackingsystem-asinglejackingstationon5mflumes.Flumesupto15mhavetwoorthreejacksinterconnectedbyageareddrive.Aslopeindicatorisprovided.
Electricaljackingisavailableasanoptionalextra,includingacontrolboxwithup/downinchbuttonsplusanadditionalemergencystopbutton.Electroniclimitswitchesdisabletheelectricaldeviceatthemaximumandminimumextentoftravel.
tEChNiCal dEtailS
Width 300mm Depth 450mm Length Asordered(multiplesof
2.5m)Note:overalllengthis3.25mlongerthantheworkingsectiondefined
Walls Toughenedglass
Bed Exclusivelyfabricatedfromstainlesssteel
Endtanks GRP(GlassReinforcedPlastic)
Sump tanks &pipework PVC(Polyvinylchloride)
&PE(polyethylene)
Pump Closecoupled centrifugal
Flowregulationvalve Handwheeloperatedbutterfly
+veslope 1:40max(1.4º) -veslope 1:200max(0.28º)
Flowmeter Electro-magnetic
Maximumflowrate 30Litres/sec
Bedstability <1.0mm(typical)at400mmwaterdepth
Sidewallstability <0.5mm(typical)at400mmwaterdepthS6MkII view from outflow end showing sump tank arrangement
ExpEriMENtal ModElS & iNStruMENtatioN
Acomprehensiverangeofexperimentalmodelsandmeasuringinstrumentsisavailableforselection.Theseprovidethebasisforalargenumberofpracticalexperimentsinopenchannelflowincludingtheuseandoperationofregulatingandgaugingstructures.
Whereverpossiblenon-corrodingmaterialshavebeenusedtoreducemaintenancetimeandincreasetheworkinglifeofthemodels.
S6-20: platE WEirS - (StaiNlESS StEEl)
>screwoperatedadjustableundershotweir
>mountingblock,forarangeofinterchangeableplateweirsthatareincludedinthesupply:
-Sharpcrestedweir(withaerationpipe)
-Rectangularnotchweir
-Trapezoidalnotchweir
-90ºveenotchweir
-60ºveenotchweir
-Sutronotchweir (linearproportionalweir)
Usercanfabricate&fitotherweirtypes.
S6-21: broad CrEStEd WEirS - (grp)
>rectangularsharpcorneredweir
>rectangularstreamlinedweir
S6-20: Rectangular overshot weir - in operation
S6-21: Broad crested weir - theory
S6-20: V-notch, Sutro and Rectangular plate weirs Trapezoidal and Sharp Crested weirs, also included.
S6-20: Rectangular overshot weir - theory
S6-21: Broad crested weir - in operation
Stable conditions are obtained for the rectangular weir by exposing both upper and lower surfaces of the nappe to atmosphere, air being admitted below and immediately downstream of the weir crest. Vent pipes are utilised to replenish lost air through entrainment with the falling water (Fig. 1)
Should air loss occur then a vacuum will be created causing the nappe to adhere to the downstream face of the weir. This condition is associated with an increase in discharge, instability of flow behaviour and is incompatible with accurate flow measurement (Fig. 2)
Aerated nappe
Aeration pipeopen
Clinging nappe
Aeration pipeblocked
This type of weir is commonly used in the gauging of discharge in open channels, particularly where accuracy and reliability are required to be combined with ease of construction and maintenance.
Shown is a traditional streamlined hump in operation, which may be compared with the crump weir.
Broad Crested Weir
Cw ≈ 0.85 to 0.9hd ≥ 0.67 huha ≥ 0.40 hu
Q=1.704CdbH3/2
advaNCEd FloW ChaNNElS
S6-22: vENturi FluME - (grp)
AsetofGRPmouldingsforinstallationinthechannelsectiontoformaventuriflume.
S6-23: ogEE WEir & MaNoMEtEr board - (grp)
Eightpressuretappings(2upstream,5downstream,1atapex)completewithmulti-tubepiezometerboard.
S6-24: daM SpillWay ModElS - (grp)
Completewiththefollowinginterchangeabledownstreamsections:
>spillwaytoe>rollerbuckettoe>apronwithremoveableenergydissipator
S6-25: SyphoN SpillWay - (aCryliC)
Completewithadjustablebreathertube.
S6-26: SElF-rEgulatiNg SyphoN - (aCryliC)
S6-27: roughENEd bEdS - (grp)
Twosectionsofdifferentroughness.Eachconsistsofthreemodulesarrangedtocovera2.5mlength.
S6-28: vibratiNg pilE
Forthestudyofvortexsheddingbypilesandtallstructures.
S6-29: liFt & drag balaNCE & ModElS - (grp)
Threemodels-largeandsmalldiametercylindersandanaerofoilsection.
S6-30: pitot tubE & MaNoMEtEr board - (grp)
Completewithtraversingcarriageandvernierheightadjustment,andaninvertedparaffinwatermanometerformagnificationofsmallpressuredifferences.
A selection of S6MkII accessories
S6-23: Ogee weir & manometer board
S6-24: Dam Spillway Models
S6-29: Lift & drag balance Models shown below
S6-27: Roughened beds
ExpEriMENtal ModElS & iNStruMENtatioN
S6-31: CruMp WEir - (grp)
Singlepressuretappingatapex,completewithpiezometertube.
S6-32: parShall FluME - (grp)
Oneofthemostwidelyusedstandingwaveflumes;allowscomparisonofhead-flowcharacteristicswiththosepublishedintheliterature.
S6-33: WSC FluME - (grp)
DevelopedbyWashingtonStateCollege,thistrapezoidalflumeconformsmorecloselytonaturalchannelsectionsandpassessedimentevenmorefreelythantheParshallFlume.
S6-35: WavE gENErator
Simple,regular,flap-typegeneratordesignedtobemountedontheflumedischargetank.
S6-36: bEaCh
WaveabsorptionbeachforusewithS6-35orS6-45toreducetheeffectofreflectedwaves.
S6-37: ZagNi FloW MoNitoriNg SyStEMS
ConsistsofafreestandingmanometerboardandinstrumentcarriagefittedwithPitottubeandinterconnectingtubing.Thissystemmaybeusedtoestablishthebasicparametersoffluidflowinthechannelincluding,invertslope,surfaceprofiles,pressureprofilesandvelocityprofiles.
S6-40: iNStruMENt CarriEr
Bothlongitudinalandtransversemovementandpositionlock.
S6-42: vEloCity MEtEr aNd MouNtiNgS
Velocityprobeanddigitalmeter,completewithmountingattachmentstochannel. Range0.6.to3m/sec.
h-1/2/3: hooK & poiNt gaugES
DesignedtobemountedonS6-40.
A selection of S6MkII accessories
S6-40: Instrument carrier
S6-36: Artificial Beach
S6-33: WSC Flume
S6-32: Parshall Flume
S6-37: Zagini Flow Monitoring Systems
H1/2/3: Hook & point gauges
S6-31: Crump weir
advaNCEd FloW ChaNNElS
S6-MKii-50 SoFtWarE CoNtrol aNd data aCquiSitioN paCKagE
TheS6-MkII-50SoftwareControlandDataAcquisitionpackageincludesaninverterwithinthecontrolconsoleforelectronicspeedcontrolfortheflowchannelpump.ItalsoincludestheS6-MkII-90dataloggingandinstrumentationsystem.
TheS6-MkII-50optionmustbespecifiedattimeoforder,andcannotberetrofittedtoexistingflumes.TheS6-MkII-90Dataloggercan be added at any time and can be retrofittedtoexistingS6-MkIIFlumes.
CoNtrol FuNCtioNS:
•Inverterspeedcontrolofcirculatingpump,eitherbyfrontpanelcontrolorfromaPC.WhenusingPCcontrolthepumpspeedcanbesetinaPIDlooptomaintainaconstantflowrate.
•Controlofpoweredjackingsystemtosetspecificslopeofbed.
data loggiNg aNd iNStruMENtatioN SyStEM (S6-MKii-90) FuNCtioNS
(IncludedwithS6-MkII-50andavailableindependently)
•Electronicinclinometertomeasureslopeofbed
•Electronicmanometertomeasure:
Pressuredistributionat10locations,Range:±690mmH2O(+/-1psi) e.g.bedtappingsortappingsonhydraulicstructuressuchasS6-23Ogeeweir.
and
Singlelowrangedifferentialpressuresensor,Range0to254mm.H2O(0to10”),e.g.forusewithS6-30Pitottube.
•2Voltageinputchannelsforusewiththeirinstrumentation,Range:±5Volts. e.g.forusewithS6-42VelocitymeterandH40Waveprobe.(Thesevoltageinputscanbescaledtoengineeringunitsinthesoftware).
•Thermistorsensortomeasurewatertemperature,Range0-50°C.
•USBinterfaceandsoftwareincludedtoallowdataloggingoftheaboveparameters.Thesoftwareincludessophisticatedsampling,calibrationandgraphplottingfacilitiesincludingtheabilitytosaveorexportthedatainMicrosoftExcelformat.
EssentialRequirement:WindowsPCwithUSBport.(notsuppliedbyArmfield).
S6-MKII-90 data logging and instrumentation systemFront and rear of the console
Rear of the console showing:Main connections, S6 Inclinometer, Thermistor and lead for user inputs.
S6-45 raNdoM WavE MaKEr
ThismachinecomprisesanelectricallydrivenlinearactuatorthatutilisesthebasehingeweirinthedischargetankoftheArmfieldS6MkIIFlumeasthepaddle.AdditionalhardwarecomprisestheS6-45Controlboxwhichinterfaceswithapersonalcomputerviaaserialinterface,withamountingbracket,RS232cableandsecuritydongle. Note:ComputernotsuppliedbyArmfield.
WavE gENEratioN SoFtWarE
>Regularwaves>Irregularwaves-filteredwhitenoise>Irregularwaves-Fourierseries>Userdefinedwavegenerationtechniques
Thisisanadvancedsoftwarepackagedesignedtosimulatelongcrestedseaconditions.ItcangenerateRegular,IrregularandSolitarywaves.
ItiscapableofrunningonanyWindowscompatible-PCwithafreeserialinterface.
Installationisbymeansofaninstallationprogram.Followinginstallationitallowsalltherelevantdimensionaldetailsofthepaddletobeenteredandsavedinafile.
Theexperimentaltransferfunctioncanbeenteredandsavedforarangeofwaterdepths.
Waveheightandperiodrequirementsareenteredatfull(prototype)scaletogetherwiththemodelscalebeingused.
Whenitisrunning,theparametersofthegeneratedseastateandarealtimegraphicaldisplayofthepaddlemovementareshownonscreen.
gENEratEd SEa StatES
Regular waves Thismethodofsignalgenerationenablesregularmonofrequencywavestobeproducedwithaspecificheightandperiod.
Irregular waves - filtered white noise method Thismethodofsignalgenerationisbasedontheprincipleofdigitallyfilteredwhitenoiseandisgeneratedinrealtime.Threesourcesofwhitenoiseareavailablebasedoneitherasingleshiftregister,multipleshiftregistersorrandomnumberswithaGaussiandistribution.Thewhitenoisesourceisgeneratedandpassedthroughadigitalfiltertoproducetherequiredpositiondemandedsignalforthepaddle.
ThecharacteristicsofthisfilterareobtainedbyperformingaFastFouriertransformationbasedonthespectralshapethathasbeenselected.
Theadvantageofthismethodisthatitcreatessequenceswhichcanbevariedfromafewsecondstoseveralyearswhilstonlyrequiringenoughmemorytoholdtheseastateparameters.
Thisabilitytocreatelongnon-repeatingsequencesisofgreatimportancewhentestingmodelswhichhaveanon-linearresponse.Extensivetestshavebeencarriedoutwhichdemonstratethatthewavesproducedusingthissystemarerealisticandthattheydofitthestatisticaltheoriesforoceanwaves.
The data inputs required are: •modelscale •spectralshape •sequencelength •sequencestartcondition •runtime
Thesequencestartconditionisaveryusefulfeaturebecauseitallowsexactlythesamerandomsequencetobegeneratedeachtimeasthisisessentialforcomparativetests.
Controls for S6-45 Random Wave Maker
advaNCEd FloW ChaNNElS
Besidesallowingtheusertocompletelydefine the spectral shape, many standard shapesareavailableincluding:
•Pierson-Moskowitz •JONSWAP •ITTC •1SSC •DarbyshireCoastal •DarbyshireOcean •Neuman Irregular waves - Fourier series method
Thismethodisequivalenttothesummationofsinewavesofdifferentfrequenciesandamplitudestoreproducethespecifiedenergyspectrum.
InfacttheoutputtimeseriesisproducedbycarryingoutaninverseFourierTransformofthespectralamplitudesafterapplyingtheappropriateTransferFunction.
Twooptionsareprovided.Inthefirstthefrequencycomponentsareproducedwithrandomphase.Inthesecondthecomponentshaverandomphaseandamplitude.
Thetechniqueisnotsuitableforproducingsignalsinrealtimesotherequiredvaluesarecomputedandstoredinafile.Thisisreadbya‘playback’programwhenthewavesaretobegenerated.Oncecreatedthesefilesmaybekeptandusedrepeatedly.
AsingleFFToperationcannotproduceatimeseriesofinfinitelengthandthelimitinthissystemhasbeensetto2048points.Longersequencesareavailablehowever,madebycarryingoutanumberofFFTsandmergingtheindividualsequencestogethertocreateoneofthelengthwhichtheuserhasrequested.
Thismethodprovidesallthespectraltypeswhichareavailablefromthefilteredwhitenoisemethod.
SpECiFiCatioNS
General Outputsignal±10volts
Standard sea states available:
>Pierson-Moskowitz >JONSWAP >ITTC >ISSC >DarbyshireCoastal > Darbyshire Ocean >Numan Sea states may be defined by: >Windspeed >WindspeedandFetch >Wavefrequencyandheight > Frequency >16Ordinatesofspectraldensity Random waves may be based on:
>Whitenoisewithsingleormultipleshiftregistersorrandomnumbers,allwithvariabletestlength
>Fourierserieswithvariableorfixedamplitude,andwithvariabletestlength
> User defined techniques Transfer Functions:
>AutomaticrecompilationofthepaddledemandsignalwithchangingTransferFunction
>InterpolationofTransferFunctionbetweendefinedfrequencies
Pleasenote: APCwithanRS232Serialportisrequired.
NB
Thisbasicrandomwavemakerconceptcanbeappliedtoallourlargeflumes.Paddleconfigurationscanvarytosuittheapplication.
Askfordetails&aquotation.
NEW
glaSS SidEd tiltiNg aNd NoN-tiltiNg StaNdard FluMES For rESEarCh
TheselargerFlumesareconsideredresearchfacilitiesandsoitneedstobenotedthatmostofthemodelsandaccessoriesavailablefortheS6-MkIIarenotavailablefortheseflumes.TheexceptionaretheWavemakers.WecanofferWavemakersfortheseflumestospecialorder.
InconstructionthetiltingversionsareverysimilarindesignandperformancetotheS6-MkIIrange.Howeverduetotheirincreasedsizetherearecertaindesigndifferencesthatreflectthegreaterloadsbeingtransportedandthehigherflowratesoffered.
Thesedifferencescomprisebedmanufacturei.e.mildsteel,laminatedwithstainlesssteelonthewettedside,arigidsupportingunderframeandtheendtanksaremanufacturedfromstainlesssteel.
Theothermajordifferencesrelatetothecapacityofthesebiggerunits.Thestandardunitsdonothavefloormountedreservoirtanks.Insteadtheyincorporateclosedloopsforre-circulation.Theseloopsaredesignedasstandardtoaccommodatesedimenttransportasafeature.Inadditionflowiscontrolledviathepump(s)whereatleastonepumphasvariablespeedcontrol.
Thejacksareelectronicallydrivenviaacontrolboxwithup/downinchbuttonsplusanadditionalemergencystopbutton.Electroniclimitswitchesdisabletheelectricaldeviceatthemaximumandminimumextentoftravel.
Thenon-tiltingoptionshavegenerallythesameperformancecriteriatothetiltingoptionsbuttheirmethodofconstructionislighterandmoreflexible.Theworkingsectionisofaprovendesignandutilizesasteelframeworkrobustenoughtosupporttheweightofwater.Thesidesaretoughenedglassandthebaseisconstructedfrommarineplywoodfacedwithstainlesssteelorcanbetoughenedglasswherevisualisationisrequired.Thesectionsaresuspendedwithinthesteelframe.Sectionsizesareapproximately2.5mlongmakingthemeasytomanhandleduringconstructionoratanytimeinthefuture.
Oneofthefeaturesofthenon-tiltingdesignistheabilitytomodifytheflumeinvariouswaysatalaterdate.
Forexample:- >Increasethelength >Re-configurethedimensions >Addviewingpanelsinthebase
Unlikethetiltingversionswhichcomeinpre-glazed2.5mmodulesthenon-tiltingversionsareflat-packedforassemblyatsite.
Bothtiltingandnon-tiltingareavailableforservicefromanexistinglaboratorysupplyorasadvisedabovewithafullyself-containedcapability.
Theyareavailableinstandardworkinglengthsof5m,7.5m,10m,12.5m,and15m.Longerlengthsareavailabletospecialorderinincrementsof2.5m.
10m Wave tank
tEChNiCal dEtailS
WavE taNKS
Usingthesamemethodsofconstructionasusedbythenon-tiltingflumesArmfieldcanofferwavetanksofsimilardimensionswithorwithoutwatercirculatingandwithsimplemonowavemakersorsophisticatedrandommachines.
Furtherdetailsonapplication.
S20/S21 S22/S23
Workingwidth 600mm 1000mm Workingdepth 600mm 1000mm Workinglength Asordered Asordered (Multiplesof2.5m) (Multiplesof2.5m)
Walls Toughenedglass Toughenedglass
Bed-tiltingversions Mild-steellaminated Mild-steellaminated withstainless-steel withstainless-steel
Bednon-tiltingversions MarinePlywoodlaminated MarinePlywoodlaminated withstainless-steel withstainless-steel orglass orglass
Endtanks Stainless-steel Stainless-steel
Pump(s) Close-coupledcentrifugal Close-coupledcentrifugal
Slope(tiltingonly) 1:40max(1.4°)+ve 1:40max(1.4°)+ve 1:200max(0.28 )̂-ve 1:200max(0.28°)-ve
Flowmeter Electro-magnetic Electro-magnetic
Maximumflowrate 120L/sec 180L/sec
Bedstability <1.0mm(typically)at <1.0mm(typically)at 540mmwaterdepth 900mmwaterdepth Sidewallstability <0.5mm(typically)at <0.5mm(typically)at 540mmwaterdepth 900mmwaterdepth Maximumparticlesize whencirculatingsediment 3mmdiameter 3mmdiameter
NEWNew computer controlled research flumes available as standard.
306
ADOBE 64/32-BIT CompaTIBleArmSoft™
Armsoft 306 - 64/32-bit Windows compatible software
For Further inFormation on the advanced Features oF the sophisticated armField soFtware visit: www.discoverarmfield.co.uk/data/armsoft
306
ArmSoft™
poWEr optioNS S20/21 & S22/23 FluMESMustbedecidedwhenordering
C 415V/3Ph/50Hz D 208V/3Ph/60HzE 308V/3Ph/50Hz F 220V/3Ph/60Hz
iNStruMENtatioN
Aselectionofinstrumentsisavailableforuseinflumes,channelsandbasins:-
H1-1toH1-11 VernierHook&PointGaugesH12-1toH12-7 Manometersincludingwater,
pressurised,water-mercuryH12-8toH12-9 PortablePressureMetersH30-1HtoH30-3H PitotTubesH33toH33-11 VelocityProbes,DigitalIndicator
andDatalogger
H40-1-1toH40-2-3 WaveProbeSystems H41LaserPIVSystem(SuitableforS8MkII&S16sizeflumesonly)
Hydraulic Instruments (H series) data sheet available on request.
ordEriNg optioNS
S6 MkII flumes - cross section 300mm wide x 450mm deepS6MkII-5.0m Basicselfcontainedflume(noelectrics)S6MkII-7.5m Basicselfcontainedflume(noelectrics)S6MkII-10m Basicselfcontainedflume(noelectrics)S6MkII-12.5m Basicselfcontainedflume(noelectrics)S6MkII-15m Basicselfcontainedflume(noelectrics)
S6MkII-C 415V/3ph/50Hz-Basicelectricscomprisingcontrolconsole&pump
S6MkII-D 208V/3ph/60Hz-Basicelectricscomprisingcontrolconsole&pump
S6MkII-E 380V/3ph/50Hz-Basicelectricscomprisingcontrolconsole&pump
S6MkII-F 220V/3ph/60Hz-Basicelectricscomprisingcontrolconsole&pump
S6MkII-SL SedimentloopforanyoftheaboveflumesS6MkII-14-1 Poweredjacksfor5.0mor7.5mflumesS6MkII-14-2 Poweredjacksfor10mor12.5mflumes
S20/S21 flumes - cross section 600mm wide x 600mm deepS20-7.5m Basicflume-Tilting(noservices)S20-10m Basicflume-Tilting(noservices)S20-12.5m Basicflume-Tilting(noservicesS20-15m Basicflume-Tilting(noservices)
S20-SERV(5/10) Servicesystem-7.5mto10m S20-SERV(12/15)Servicesystem-12.5mto15m
S21-7.5m Basicflume-Non-Tilting(noservices) S21-10m Basicflume-Non-Tilting(noservices) S21-12.5m Basicflume-Non-Tilting(noservices) S21-15m Basicflume-Non-Tilting(noservices)
S21-SERV(5/10)Servicesystem-7.5mto15m
S22/S23 flumes - cross section 1000mm wide x 1000mm deepS22-7.5m Basicflume-Tilting(noservices)S22-10m Basicflume-Tilting(noservices)S22-12.5m Basicflume-Tilting(noservicesS22-15m Basicflume-Tilting(noservices)
S22-SERV(5/10) Servicesystem-7.5mto10m S22-SERV(12/15)Servicesystem-12.5mto15m
S23-7.5m Basicflume-Non-Tilting(noservices) S23-10m Basicflume-Non-Tilting(noservices) S23-12.5m Basicflume-Non-Tilting(noservices) S23-15m Basicflume-Non-Tilting(noservices)
S23-SERV Servicesystem-7.5mto15m
other sizes available on request.
WITH DISCOVER
2 -YR WARRANTY ON ALL ARMFIEL
D PRO
DUCT
S
<EXTENDED> WARRANTY
2 years
©2012 armfield Ltd. all rights reserved We reserve the right to amend these specifications without prior notice. E&OE 0112/3k/SO2796Computers are not supplied by Armfield.
Head Office: Armfield Limited Bridge House, West street, Ringwood, Hampshire. BH24 1DY england
Telephone: +44 1425 478781Fax: +44 1425 470916e-mail: [email protected]
U.S. Office: Armfield inc. 436 West Commodore Blvd (#2) Jackson, NJ 08527Telephone: (732) 928 3332Fax: (732) 928 3542e-mail: [email protected]
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Innovators in Engineering Teaching Equipment
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NEWNew computer controlled research flumes available as standard.
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