简介:Recentexperimentsontheimplosionsof15-mmlongand2-μmthickaluminumlinershavingadiameterof12.8mmhavebeenperformedontheprimaryteststand(PTS)facility.Thestratifiedstructuresareobservedasalternatingdarkandlighttransversestripesinthelasershadowgraphimages.Thesestriationsperpendiculartothecurrentflowareformedearlyintheimplosion,i.e.,atthestagewhenthebulkofthematerialmasswasalmostatrest.Atwo-dimensional(2D)magnetohydrodynamics(MHD)codeisemployedtosimulatethebehavioroflinerdynamicsintheearlyphases.Itisfoundthatthestriationsmaybeproducedbytheelectrothermalinstability(ETI)thatresultsfromnon-uniformJouleheatingduetothecharacteristicrelationbetweentheresistivityandthetemperature.In2Dsimulations,thestratifiedstructurescanbeseenobviouslyinbothdensityandtemperaturecontoursasthelinerexpandsrapidly.Byanalyzinginstabilityspectrum,thedominantwavelengthsoftheperturbationsare8.33μm–20.0μm,whichagreequalitativelywiththetheoreticalpredictions.ItisalsointerestingtoshowthatETIprovidesasignificantseedtothesubsequentmagnetoRayleigh–Taylor(MRT)instability.