An experimentalstudyofair–waterTaylorflowandmasstransferinside square microchannels

Flow andmasstransferpropertiesunderair–waterTaylorflowhavebeeninvestigatedintwosquare microchannels withhydraulicdiametersof400and200m. ExperimentaldataonTaylorbubblevelocity, pressure dropandliquidsidevolumetricmasstransfercoefficient(kLa) havebeenpresented.Itwasshown that themeasuredTaylorbubbleve...

Full description

Saved in:
Bibliographic Details
Published in:Chemical engineering science 2009, Vol.16, p.3697-3708
Main Authors: Yue, Jun, Luo, Lingai, Gonthier, Yves, Chen, Guangwen, Yuan, Quan
Format: Article
Language:English
Subjects:
Environmental Sciences
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Flow andmasstransferpropertiesunderair–waterTaylorflowhavebeeninvestigatedintwosquare microchannels withhydraulicdiametersof400and200m. ExperimentaldataonTaylorbubblevelocity, pressure dropandliquidsidevolumetricmasstransfercoefficient(kLa) havebeenpresented.Itwasshown that themeasuredTaylorbubblevelocityinsquaremicrochannelscouldbewellinterpretedbasedupon an approximatemeasurementoftheliquidfilmprofiletherein.Then,theobtainedtwo-phasefrictional pressure dropvaluesinbothmicrochannelswerefoundtobesignificantlyhigherthanthepredictions of thecorrelationproposedbyKreutzeretal.[2005b.Inertialandinterfacialeffectsonpressuredropof Taylor flowincapillaries.A.I.Ch.E.Journal51,2428–2440]whentheliquidslugwasveryshort,which can beexplainedbytheinadequacyoftheircorrelationtodescribetheexcesspressuredropcausedby the stronginnercirculationinsuchshortliquidslugs.Anappropriatemodificationhasbeenmadetothis correlation inordertoimproveitsapplicabilityinmicrochannels.Finally,theexperimental(kLa) values in themicrochannelwithhydraulicdiameterof400m werefoundtobeinpooragreementwiththose predicted bytheexistingcorrelationsproposedforcapillarieswithdiametersofseveralmillimeters. The observeddeviationwasmainlyduetothefactthatmasstransferexperimentsinthismicrochannel actually correspondedtothecaseofshortfilmcontacttimeandratherpoormixingbetweentheliquid film andtheliquidslug,whichwasnotinaccordancewithmasstransferassumptionsassociatedwith these correlations.Anewempiricalcorrelationhasbeenproposedtodescribemasstransferdatainthis microchannel.
ISSN:0009-2509