虹吸管道非穩態多相流數值模擬與試驗研究摘要：本研究通過數值模擬和試驗研究，對虹吸管道的非穩態多相流特性進行了分析和探討。針對虹吸管道中的氣液兩相流動問題，采用歐拉-拉格朗日方法建立了數值模型，通過計算流場各項指標得到了流動特性和壓力變化規律。同時，本文還構建了針對虹吸管道氣液兩相流的實驗模擬平臺，并進行了一系列試驗。試驗結果顯示，虹吸管道中液位高度、管道角度、管徑以及進口液體流量對虹吸效應均有較大影響，其中液位高度和管道角度的影響最為顯著。通過對比數值模擬和試驗結果，驗證了模型的可靠性和精度，得到了更加準確的多相流動特性和虹吸效應規律。本文的研究結果不僅可為虹吸式液體輸送系統的設計和優化提供理論支持，還對多相流動問題的深入研究和應用具有一定的參考意義。

關鍵詞：虹吸管道；非穩態多相流；歐拉-拉格朗日方法；數值模擬；試驗研究

Abstract:Inthisstudy,thecharacteristicsofunsteadymultiphaseflowinsiphonpipelineswereanalyzedanddiscussedthroughnumericalsimulationandexperimentalresearch.Fortheproblemofgas-liquidtwo-phaseflowinsiphonpipelines,anumericalmodelwasestablishedusingtheEuler-Lagrangemethod,andtheflowcharacteristicsandpressurechangeswereobtainedbycalculatingvariousflowfieldindicators.Atthesametime,thispaperalsoconstructedanexperimentalsimulationplatformforgas-liquidtwo-phaseflowinsiphonpipelinesandconductedaseriesofexperiments.Theresultsshowedthattheliquidlevelheight,pipelineangle,pipediameter,andinletliquidflowrateallhadasignificantimpactonthesiphoneffectinthesiphonpipeline,ofwhichtheliquidlevelheightandpipelineanglehadthemostsignificantimpact.Bycomparingthenumericalsimulationandexperimentalresults,thereliabilityandaccuracyofthemodelwereverified,andmoreaccuratemultiphaseflowcharacteristicsandsiphoneffectlawswereobtained.Theresearchresultsofthispapercannotonlyprovidetheoreticalsupportforthedesignandoptimizationofsiphonliquidtransportationsystemsbutalsohavecertainreferencesignificanceforthein-depthstudyandapplicationofmultiphaseflowproblems.

Keywords:siphonpipeline;unsteadymultiphaseflow;Euler-Lagrangemethod;numericalsimulation;experimentalresearchThesiphoneffectisawidelyusedprincipleinmanyliquidtransportationsystems.Toensurethesafeandefficientoperationofthesesystems,itisessentialtothoroughlyunderstandtheflowcharacteristicsandsiphoneffectinmultiphaseflow.Inthisstudy,theunsteadymultiphaseflowbehaviorinasiphonpipelinewasinvestigatedusingtheEuler-Lagrangemethodandvalidatedbyexperimentalresearch.

ThenumericalsimulationwasconductedbysolvingtheNavier-Stokesequationsfortheliquidphaseandthekinematicequationsforthegasphase.ThegoverningequationswerediscretizedusingafinitevolumemethodandsolvedusingtheSIMPLEalgorithm.TheLagrangianparticletrackingmethodwasusedtosimulatethemovementofparticlesinthegasphase.

Onthebasisofnumericalsimulation,themultiphaseflowcharacteristicsofthesiphonpipelinewereanalyzed.Thepressuredistributionandvelocitydistributionoftheliquidphasewereobtained.Thesiphoneffectwasobservedtobestronglyinfluencedbythecharacteristicsofthemultiphaseflow.Theresultsindicatedthatthegas-liquidinterfacewasunstableduetotheinteractionbetweenthephases,whichledtoafluctuationinthepressureandvelocityoftheliquidphase.

Inaddition,theexperimentalresearchwasconductedtoverifytheaccuracyofthenumericalsimulationresults.Thetransientpressureandliquidflowrateweremeasuredatdifferentpositionsinthesiphonpipeline.Theexperimentalresultswereingoodagreementwiththenumericalsimulationresults,indicatingthatthenumericalsimulationmethodwasreliableforanalyzingthemultiphaseflowbehaviorinthesiphonpipeline.

Basedontheresearchresults,moreaccuratemultiphaseflowcharacteristicsandsiphoneffectlawswereobtained.Thesefindingscanprovidevaluableguidanceforthedesignandoptimizationofsiphonliquidtransportationsystems.Moreover,theresearchresultshavecertainreferencesignificanceforthein-depthstudyandapplicationofmultiphaseflowproblemsInaddition,theresearchalsohighlightedsomepotentialchallengesthatcouldariseinsiphonpipelinesystems.Forexample,theflowpatternandpressuredropofthegas-liquidmixtureinthepipelinemaychangeduetofactorssuchaschangesinfluidcomposition,pipelinegeometryorambienttemperature.Therefore,itisimportanttoconsiderthesefactorsduringthedesignandoperationofsiphonpipelines.

Moreover,theresearchshowedthatthepressuredistributionalongthesiphonpipelinewasuneven,withahigherpressuredropoccurringinthedownwardbranchofthepipelinethanintheupwardbranch.Thiscouldleadtolowerflowratesandpressuredropsthanpredictedintheupwardbranch,andhigherthanpredictedinthedownwardbranch.Thus,itisnecessarytoconsiderthesepressureimbalanceswhendesigningandoperatingsiphonpipelines.

Inconclusion,theresearchonmultiphaseflowbehaviorinsiphonpipelineshasprovidedvaluableinsightsintotheflowcharacteristicsandsiphoneffectlawsofthesesystems.Thesefindingsarecrucialinoptimizingthedesignandoperationofsiphonpipelinestoensurepropertransportofliquidsoverlongdistances.Futureresearchcouldfocusonaddressingthechallengesandlimitationsofthesesystems,particularlyinimprovingthepressuredistributionandminimizingthepressurelossesduringoperationThereareseveralareasforfutureresearchonsiphonpipelines,particularlyonthechallengesandlimitationsofthesesystems.

Oneaspectthatneedstobeaddressedisthepressuredistributionalongthepipeline.Insiphonpipelines,pressureimbalancescanoccurduetotheunevendistributionoffluidpropertiesorachangeindirection.Thesepressureimbalancescancauseflowinstabilitiesandreducetheefficiencyofthesystem.Therefore,futureresearchcouldinvestigatetechniquestoimprovethepressuredistributionalongsiphonpipelines,suchasbyincorporatingpressureequalizationchambersordevelopingbetterflowcontrolmechanisms.

Anotherareaofresearchisonminimizingpressurelossesduringoperation.Frictionallossesoccurinallpipelinesandcannegativelyimpacttheperformanceofthesystem.Insiphonpipelines,theselossescanoccurindifferentwaysdependingontheflowregime,suchasviscosityeffectsorfluidseparation.Futureresearchcaninvestigatewaystoreducefrictionallossesinsiphonpipelines,suchasbyoptimizingthepipediameter,improvingthefluidproperties,ordevelopingnovelcoatingmaterialstoreducefriction.

Moreover,researchcouldfocusonunderstandingtheinteractionsbetweenmultiphaseflowbehaviorandsiphonpipelines.Themovementofmultiphasefluidsiscomplexandcancauseunexpectedbehaviorinsiphonpipelines,suchasflooding,gasentrainment,orslugflow.Therefore,futureresearchcouldexploretherelationshipbetweenmultiphaseflowbehaviorandsiphonpipelinestodevelopmoreaccuratemodelsanddesigncriteriaforthesesystems.

Lastly,thereisaneedtoinvestigatetheenvironmentalimpactofsiphonpipelines.Whilesiphonpipelinescanofferacost-effectiveandefficienttransportsolution,theycanalsohavenegativeimpactsontheenvironment,suchasalteringwaterecosystemsorreleasingpollutantsintothewater.Futureresearchshouldaimtoquantifyandmitigatetheseenvironmentalimpactstoensuresustainableuseofsipho