管壳式换热器沸腾换热实验分析

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1、万方数据Abs仃actAbstractAsanimportantequipmentinpetroleumandchemicalindustry,Theshellandtubeheatexchangerplayalargeroleinconservingenergyandreducingemissionsintheindustry．Inrecentyears，withthedevelopingofheattransfertechnology,Thespiralflattubeasakindofwidelyusedheatexchangeralsodevelo

2、pesfastly．thescholarsathomeandabroaddidresearchesOHtwophaseflowboilingflowandheattransfercharacteristicsoneafteranother．Thereisadeviationresultsfromdifferentresearchersduetothecomplexityoftwophaseflowandthelimitationoftheexperimentalconditions．Inadditionthereislessresearchontheeff

3、ectsofheattransferandflowforthenon—condensablegas．Sothisarticleisbasedonthegas-liquidtwophaseflowmediuminthefiatspiraltubeheatexchangertubebundles．IntheprocessoftwophaseflowboilingheattransferexperimenttoaddaliRleamountofnoncondensablegas．Themainresearchworkisasfollows：1、Throughth

4、eanalysisofexperimentaldata，thetwophaseflowandheattransfercharacteristicsarealongwiththeReynoldsnumbegtheprandtlnumber,quality，rateofgasandliquidphasechangelawsofimportvolumeflowtochange．intermsofflowcharacteristicsfrictionalresistanceincreasewiththeincreaseofthepressuredropalongw

5、iththeprandtlnumber；Withinacertainrange，frictionalresistancedidcyclicalfluctuationswiththeincreaseofgasrate．Thefluctuationcycleincreasesgradually,andthewavedidamplitudealongwiththeincreaseoftheliquidimportvolumeflow．intermsofheattransfercharacteristics，Intheconditionsofpresenceofn

6、oncondensablegastheaverageNusseltnumberincreaseswiththetwo—phaseflowboilingheattransferofReynoldsnumber．Intheprocessofboilingheatwiththelowgasflowrate，thefluxdensitydecreased谢mtheincreaseofgasrate．Itshowedcyclicalfluctuationswiththefurtherincreaseofgasrate．2、Onthebasisofaboveexper

7、iments，experimentwascondusctingbychangingthepitch．Explorethedifferentpitchsizesdidtheinfluenceforthetwo—phaseboilingflowandheattransfercharacteristics．Findwhendidtheexperimentwithsmallpitch，TheincreasingamplitudeofNusseltnumberwasaccompaniedwiththeincreasingofReynoldsnumber,andthe

8、maximumvalueofNusseltnumberislarg