采用粒子图像测速来测量间隔区填充管道内液体和液体/气体流动液体速度场分布形态

Liquid andliquid/gasflowsthroughspacerfilledchannelswerestudiedusingParticleImagingVelocime- try (PIV)toprovideexperimentalsupportforvelocitydistributionsobtainedfromComputationalFluid Dynamics studiesavailableintheliterature.ItisshownthatPIVisasuitabletechniqueformeasuring velocity profilesinspacerfilledchannels,althoughcarehastobetakenwheninterpretingtheresults. PIV measurementswerecarriedoutforanentireflowcell(5cm×15 cm),asmallerareaofroughly 7mm×8mmandforasinglespacercell(2.5mm×3 mm).Theexperimentalresultsshowthatfluidflow is welldistributedacrosstheentireflowcellinthecaseofsingle-phaseflow.Therecordingsofthesingle spacer cellshowedthatliquidflowismainlyparalleltothespacerfilamentsandthereforethedirec- tion offlowchanges90◦ over theheightofthechannel.Introductionofairbubblesintroducedstrong local velocitygradients.Theliquidvelocityintwo-phaseflowsisshowntobemoreunsteadythanin the caseofsingle-phaseflow,whichisadvantageouswhentryingtopreventfoulingorconcentration polarization.