Experiment Osbourne Reymold Che486 Uitm

E X PE R IM EN T4 :O SB O URN ER EY NOLD SN URS Y A FIQ AHB IN TIM OHAM ADF R ID US( 2 022622316)S IT IN ORA FID AHB IN TIL EG IM AN( 2 022899644)I Z D IH ARR A IM IB INI B RA HIM( 2 022664234)M UHAM MADN AQIBB INA BD .N ASIR( 2 022841974)A bstr a ct-Thislabr eportdescribesther epr oductionandanalysisofOsborneReynolds'classicexperimenttoinvestigatetheconceptoffluidflowandReynoldsnumber .Theexperimentaimedtounderstandthetransitionfr omlaminartoturbulentflowinapipebyvaryingflowratesandobservingther esultingpatterns.ThestudyinvolvedmeasuringthecriticalReynoldsnumberandunderstandingitssignificanceinfluiddynamics.I .I N TR O DUCTIO NInnatureandinlaboratoryexperiments,flowmayoccurundertwoverydif ferentregimes:laminarandturbulent.Inlaminarflows,fluidparticlesmoveinlayers,slidingovereachother ,causingasmallener gyexchangetooccurbetweenlayers.Laminarflowoccursinfluidswithhighviscosity ,movingatslowvelocity .Theturbulentflow ,ontheotherhand,ischaracterizedbyrandommovementsandintermixingoffluidparticles,withagreatexchangeofener gythroughoutthefluid.Thistypeofflowoccursinfluidswithlowviscosityandhighvelocity .ThedimensionlessReynoldsnumberisusedtoclassifythestateofflow .TheReynoldsNumberDemonstrationisaclassicexperiment,basedonvisualizingflowbehaviorbyslowlyandsteadilyinjectingdyeintoapipe.ThisexperimentwasfirstperformedbyOsborneReynoldsinthelatenineteenthcentury .Laminarflow(Re2300)is"Random".Irregularflowthatischaracterizedbytinywhirlpoolregions.Thevelocityofthisfluidisnotconstantateverypoint.Itoccursathighflowrate.T ransitionalflow(Reisapproximately2300).isamixtureoflaminarandturbulentflow ,withturbulenceinthecenterofthepipe,andlaminarflowneartheedges.Figure4.1Laminarflow ,T ransitionalflowandT urbulentflowI I.O BJE C TIV ES1.T ocalculateReynold'snumber(R).2.T odeterminewhethertheflowislaminar ,transitional,orturbulent.I II.T H EO RYThetheorythatdistinguishesbetweenlaminarandturbulentflowisnamedafterOsborneReynolds,awell-knownBritishengineerwhodiscoveredthedistinctcharacteristicsofthesetwoformsofflow .TheReynoldsnumber ,adimensionlessparameter ,iscommonlyusedinfluidmechanic sresearch.TheReynoldsnumberiscalculatedusingthefollowingequation:.............(Eq4.1)PipeFlowConditionsThevariableLisfrequentlyusedtodenotethediameterofapipeoranyothercircularconduitthatallowswatertopassthrough.IftheReynoldsnumbergoesbelow2100,thefluidflowwithinthepipewilldemonstratesmoothnessandlaminarity .WhentheReynoldsnumberinapipefallsbetween2100and4000,theflowischaracterizedastransitional.WhentheReynoldsnumberexceeds4000,itisproventhatturbulencebegins.Theviscosityofthefluidisanothercharacteristicthatdeterminesthetransitionfromlaminartoturbulentflow .Whendealingwithafluidwithahighviscosity ,itismucheasiertogenerateaphenomenonknownasturbulentflow .T emperaturecanalsoaf fecttheviscosityofafluid.LaminarFlowTheabsenceofcontactormixingacrossshearplanes,withallstreamlinesmaintainingparallelcourses,wasdiscoveredtocharacterizethestabilityoflaminarflow .Thepreviouslymentionedsituationwasreferredtoas"laminarflow ."Giventhecircumstances,thedyewillremainasacontinuous,consistent,andplainlyrecognizablepartofthefluidmotion.T ransitionalFlowLaminarandturbulentflowcharacteristicscancoexistinaflowpatternknownastransitionalflow .Thecoreofthepipeseesturbulentflowinthisflowregime,whereasthepipe'sbordersexperiencelaminarflow .Becausetheamountofener gylostduetofrictionvariesbyflow ,itispossibletoforecastthebehaviorsofeachoftheseflowsusingauniquesetofequations.T urbulenceFlowItisadynamicfluidmotionconditiondistinguishedbytheintricateinterplayofstreamlines,whichcausesshearplanestobedisturbedandfluidstobethoroughlymixed.T urbulentflowisoneofthepossiblestatesinturbulentflow .Inthiscase,thedyewillpermeatethroughoutthewaterandengageinachemicalreactionwithit.Itiscurrentlyimpossibletoestablishthecolorofthefounddye.I V .P R O CED UREW aterwasallowedtoenterthroughthewatersupplynozzleintothewatertank,andthentheflowwasadjustedusingthe"ControlvalveandDrainvalve"insuchawaythatthewaterlevelinthewatertankwasalmostconstant(neitherrosenorfell).Next,themeteringtapoftheinkreservoirwasopened,andinkflowedthroughthetestpipesection.W ithoutdisturbingtheflowrate,wemeasureditsvolumeflowratethroughthedrainvalveusingastopwatchandmeasuringtank.Then,wemeasuredthevolumeflowrateofinletwaterthroughthewatersupplynozzleusingastopwatchandmeasuringtank.V .R ESU LTCalculateflowratebyusingthisformula;Calculateflowrate;=� ��� � (�) � (�)0.0 01(�3)1(�)CalculateReynoldsNumberbyusingthisformula;ReynoldsNumber;= � � � � � � � � � � � �� (�) Area=1.91x10- 4m2Diameter=0.0156mKinematicviscosity=0.89x10- 6m2/sLaminarflowV olume(L)T ime(s)Flowrate,Q(m3/s)ReynoldsNumber0.1185.5x10- 65040.115.106.62x10- 5607.520.16.761.48x10- 51358T ransitionalflowV olume(L)T ime(s)Flowrate,Q(m3/s)ReynoldsNumber0.14.372.30x10- 521 100.13.412.90x10- 526610.13.053.28x10- 53010T urbulentflowV olume(L)T ime(s)Flowrate,Q(m3/s)ReynoldsNumber0.11.825.5x10- 550470.12.074.8x10- 544040.12.204.5x10- 54130V I.D IS C U SSIO NThepurposeoftheexperimentwastolookatthecharacteristicsoftheliquidflowinthepipe,whichisalsoutilizedtocalculatetheReynoldsnumberforeachflowcondition.Theexperimentwasalsoconductedtoobserveandunderstandtheflow'sbehaviorandtodeterminethelaminar ,transitional,andturbulentflowranges.Additionally ,wemustusetheReynoldsnumberformulatofindtheReynoldsnumber .T oconducttheexperiment,OsbourneReynoldsequipmentwasused.Inthisexperiment,threedistinctformsofflowarebeingobserved.Firstof f,alaminarflowisakindofflowinwhichtheparticlestravelinastraightlineasthin,parallelsheets.Asteadystatewhereallstreamlinesfollowparallelpathsisreferredtoaslaminarflow .Thedyewillcontinuetobeclearlydistinguishableasasolidcoreinthissituation.T urbulentflowisaformofflowwheretheparticlestravelinazigzagpattern.Whenstreamlinescontact,shearplancollapseandmixingoccur ,whichisknownasturbulentflow .Theprocessofchangingfromlaminartoturbulentflowisgradualwhentheflowrateisraised.T ransitionalflowisthenamegiventothisareaofchange.Whenturbulencehappens,thiswillshowupasameanderingdyestreambeforedispersing.Lastbutnotleast,adisturbanceisproducedwhenaflowtransitionsfromlaminartoturbulentorviceversa.Thisisknownasatransitionalflow .TheinformationgatheredandrecordedintableshowtheReynoldsNumberforeachexperiment.Forlaminarflow ,theReynoldsvalueswere607.518,1358,and504504.TheaverageReynoldsReynoldsnumberwas823.17.TheReynoldsnumberlessthan2100wasdemonstratedtobealaminarflow .Next,Forthetransitionflow ,theReynoldsnumberswere3010,2661,and21 10.2593.67wastheaverageReynoldsnumberforthetransitionalflow .Reynoldsnumbersbetween2100and4000wereshowntorepresentatransitionalflow .Lastbutnotleast,Forturbulentflow ,theReynoldsnumberswere4129.65,4404,and5047.Forturbulentflow