Author/Authors :
V.E.Badalassi، نويسنده , , S.Banerjee، نويسنده ,
Abstract :
Whenasystemsuchasabinaryliquidiscooledrapidlyfromahomogeneousphaseintoatwo-phaseregion,domainsofthetwoequilibriumphasesformandgrow(coarsen)withtime.Intheabsenceofexternalforcing,suchasbygravityoranimposedshearflow,adynamical-scalingregimeemergesinwhichthedomainmorphologyisstatisticallyself-similaratdifferenttimes,withanoveralllength-scale(coarseningscale)thatgrowswithtime.Inthefirstpartofthepaper,thescalingphenomenologywillbereviewedandthetime-dependenceofthecoarseningscalewillbediscussedinthecontextofanumberofdifferentphysicalsystemsandscalingregimes.Inthesecondpart,theinfluenceofexternaldrives,inparticulargravityandshearflow,willbeaddressedandrecentresultsreviewed.Inparticular,wefindthatmultiplelengthscalesemergesinceintheshearcasethesystemcoarsensmorerapidlyinthemeanflowdirectionwhileinthegravitycasethecoarseningismorerapidinthedirectionofthegravity.Wecharacterizedthescalesbycalculationsoftheanisotropicgrowthlaws.Furtherfortheshearweshowthatitispossibletocontroltheasymptoticmorphologyofthephaseseparationinordertoobtaineitherlamellaeorcylindricalstructuresandpotentiallycreateforexamplenano-conductivewiresormaterialswithparticularopticalproperties.Investigatinggravitationaleffectswefindthatscalinglawsaresignificantlyaffectedevenforsmalldensitymismatchorlowgravity,andthegrowthmechanismhassomesimilaritiestothesedimentationprocess.
