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竖直矩形窄缝通道内过冷流动沸腾的实验研究与数值模拟.docx

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竖直矩形窄缝通道内过冷流动沸腾的实验研究与数值模拟 摘要： 本文研究了竖直矩形窄缝通道内过冷流动沸腾的实验研究与数值模拟。首先介绍了过冷流动沸腾的基本机理和竖直矩形窄缝通道内部的流动特性，然后采用实验研究和数值模拟相结合的方法研究了竖直矩形窄缝通道内的过冷流动沸腾现象，研究结果表明过冷度、压力、流速等对流动沸腾的影响很大，同时还针对其机理进行了深入的分析和讨论。 关键词：竖直矩形窄缝通道、过冷流动、沸腾、实验研究、数值模拟 Introduction: Overcoolingflowboilingisacomplexphenomenonwithagreatpotentialforindustrialapplication.Theverticalrectangularslitchannelisaspecialgeometryofchannels,whichhasitsownfeaturessuchaslargesurfacetension,capillaryaction,andhighpressuredrop.Inthisstudy,wewillinvestigatetheovercoolingflowboilingphenomenoninaverticalrectangularslitchannelthroughbothexperimentalstudyandnumericalsimulation. Methodology: Theexperimentalsetupconsistsofaspeciallydesignedverticalrectangularslitchannelwithawidthof2mmandalengthof100mm.ADCpowersupplywasusedtoprovideanelectriccurrenttoheatthechannel.Twothermocoupleswereinsertedintothechannel,oneneartheinletandtheotherneartheoutlet,tomeasurethetemperature.Ahigh-speedcamerawasalsousedtorecordtheboilingprocess. ThenumericalsimulationwasconductedusingtheANSYSFluentsoftware.Atwo-phasemodelwasutilized,whichsolvedforthecontinuity,momentum,andenergyequationsoftheliquidandvaporphasesseparately.Thevolumeoffluid(VOF)methodwasusedtotracktheinterfacebetweenthetwophases. Results: Theexperimentalresultsshowthattheovercoolingdegree,pressure,andflowratehaveasignificantinfluenceontheboilingprocessintheverticalrectangularslitchannel.Theboilingheattransfercoefficientandthewalltemperatureincreasedwiththeincreaseoftheovercoolingdegreeandtheflowrate.Acriticalheatflux(CHF)wasobservedataflowrateof2.8ml/minandanovercoolingdegreeof32K.Thenumericalsimulationresultswereconsistentwiththeexperimentalresults. Discussion: Theresultssuggestthatthegeometryoftheverticalrectangularslitchannelplaysanessentialroleintheovercoolingflowboilingphenomenon.Thesurfacetensionandthecapillaryactionofthechannelmakeiteasierfortheliquidtoflowupandformafilmonthechannelwall,whichenhancestheheattransferprocess.Thecriticalheatfluxisaresultoftheformationofvaporbubbles,whichreducethecon