大氣壓等離子體射流自脈沖現(xiàn)象研究大氣壓等離子體射流自脈沖現(xiàn)象研究

摘要：大氣壓等離子體射流技術(shù)是目前較為廣泛應(yīng)用于工業(yè)、醫(yī)學(xué)和生物等領(lǐng)域的一種先進技術(shù)。在實際應(yīng)用中，射流的方向、形態(tài)、流量和頻率是影響等離子體效應(yīng)和射流應(yīng)用效果的重要因素之一。本研究針對大氣壓等離子體射流自脈沖現(xiàn)象展開研究，主要通過文獻調(diào)研、數(shù)值模擬和實驗驗證相結(jié)合的方法，探究自脈沖現(xiàn)象的成因及其對射流的影響。結(jié)果表明：自脈沖現(xiàn)象是來自等離子體射流產(chǎn)生的電磁場與氣體流場相互作用形成的動態(tài)平衡，其相關(guān)參數(shù)與射流實驗條件及氣體性質(zhì)有關(guān)。此外，自脈沖現(xiàn)象對射流穩(wěn)定性和能量利用效率產(chǎn)生較大影響，尤其在射流在醫(yī)學(xué)和生物應(yīng)用中受到更為關(guān)注。總之，本研究對于深入理解大氣壓等離子體射流機理和優(yōu)化射流應(yīng)用具有重要的科學(xué)與工程意義。

關(guān)鍵詞：大氣壓等離子體射流；自脈沖現(xiàn)象；成因；數(shù)字模擬；實驗驗證

Abstract:Atmosphericpressureplasmajet(APPJ)isanadvancedtechnologywidelyusedinindustry,medicineandbiology.Thedirection,morphology,flowrateandfrequencyofthejetareimportantfactorsaffectingtheplasmaeffectandjetapplicationeffect.Thisstudyfocusedontheself-pulsingphenomenonofAPPJandusedacombinationofliteraturesurvey,numericalsimulationandexperimentalverificationtoexplorethecauseandimpactoftheself-pulsingphenomenononthejet.Theresultsshowedthattheself-pulsingphenomenonisadynamicequilibriumformedbytheinteractionbetweentheelectromagneticfieldgeneratedbytheplasmajetandthegasflowfield,anditsrelevantparametersarerelatedtotheexperimentalconditionsandgasproperties.Inaddition,theself-pulsingphenomenonhasasignificantimpactonthestabilityandenergyefficiencyofthejet,especiallyinmedicalandbiologicalapplications.Ingeneral,thisstudyisofsignificantscientificandengineeringsignificanceforadeepunderstandingofthemechanismofAPPJandtheoptimizationofjetapplications.

Keywords:atmosphericpressureplasmajet;self-pulsingphenomenon;cause;numericalsimulation;experimentalverificationTheatmosphericpressureplasmajet(APPJ)isapromisingtechnologywithawiderangeofapplicationsinvariousfieldsincludingbiomedical,environmentalandindustrialsectors.However,theself-pulsingphenomenonobservedinAPPJscansignificantlyaffecttheireffectivenessandstability.Therefore,thereisapressingneedtoinvestigatetheunderlyingcausesofthisphenomenon.

NumericalsimulationisaneffectiveapproachtounderstandthecomplexphysicalandchemicalprocessesthatoccurinAPPJs,andhasbeenusedtoinvestigatetheself-pulsingphenomenon.Theresultsofnumericalsimulationshaverevealedthattheself-pulsingphenomenoniscausedbytheinteractionbetweentheplasmaandthegasflow.Specifically,theperiodicoscillationoftheplasmadischargeinducesaperiodicchangeinthegastemperatureandpressure,whichinturnleadstoaperiodicvariationofthegasflowrate.

Experimentalverificationisessentialtovalidatetheresultsofnumericalsimulations.Severalexperimentalstudieshaveconfirmedtheexistenceoftheself-pulsingphenomenoninAPPJs.Forexample,high-speedimagingandacousticmeasurementshavedemonstratedaperiodicfluctuationinthesoundandlightemissionoftheplasma.Additionally,measurementsofthegasflowratehavealsoshownperiodicvariationsintheflowrate.

Theself-pulsingphenomenonhasasignificantimpactonthestabilityandenergyefficiencyoftheAPPJ.Inbiomedicalapplications,theself-pulsingcanleadtoanon-uniformdistributionoftheplasmatreatment,reducingitseffectiveness.Moreover,thefluctuationofthegasflowratecanaffectthemasstransportofreactivespeciesandpotentialcontaminationsintothesystem.Therefore,furtherresearchisrequiredtooptimizethestabilityandenergyefficiencyoftheAPPJinvariousapplications.

Inconclusion,theself-pulsingphenomenonisacomplexprocessthatoccursinatmosphericpressureplasmajets.Numericalsimulationandexperimentalverificationhaveshedlightontheunderlyingcausesofthisphenomenon.ThefindingsfromthisstudyaresignificantforabetterunderstandingofthemechanismofAPPJandtheoptimizationofthejetapplicationsAdditionally,theself-pulsingphenomenonisnotlimitedtoatmosphericpressureplasmajetsandcanalsooccurinotherplasmasourcessuchasmicroplasmadevicesandsurfacebarrierdischarges.Therefore,furtherresearchonself-pulsingindifferentplasmasourcesisnecessarytodetermineifthesamephysicalmechanismsareinvolved.

Furthermore,whiletheself-pulsingphenomenoncanbebeneficialforcertainapplications,itcanalsobedetrimentalinothers.Forexample,inplasmamedicinewherethegoalistokillbacteriawithoutdamaginghealthycells,self-pulsingcanleadtouneventreatmentandpotentiallyharmfuleffectsonhealthytissue.Therefore,abetterunderstandingoftheconditionsthatleadtoself-pulsingandhowtocontrolitiscrucialforthedevelopmentofsafeandeffectiveplasma-basedmedicaltreatments.

Lastly,thestudyofself-pulsinginatmosphericpressureplasmajetsalsohighlightstheneedforinterdisciplinaryresearchinvolvingplasmaphysics,fluiddynamics,andmaterialsscience.Thecomplexanddynamicnatureofplasmainteractionswiththesurroundinggasandmaterialsurfacesrequiresadeepunderstandingofthesefieldstooptimizeplasmatechnologiesforawiderangeofapplications.

Overall,thestudyofself-pulsinginatmosphericpressureplasmajetsisanimportantareaofresearchthathasthepotentialtoimpactawiderangeoffields.Byfurtherunderstandingthemechanismsandeffectsofself-pulsing,researcherscanoptimizeplasmatechnologiesforvariousapplications,frommedicaltreatmentstoadvancedmanufacturingprocessesInadditiontothestudyofself-pulsinginatmosphericpressureplasmajets,therearemanyotherareasofresearchinthefieldofplasmatechnologythatareofgreatimportance.Onesuchareaisthedevelopmentofplasma-basedmedicaltreatments,particularlyforcancer.

Plasmahasbeenshowntohavepotentialincancertreatmentduetoitsabilitytoselectivelytargetcancercellswhileavoidingdamagetohealthycells.Thisisbecauseplasmageneratesreactiveoxygenandnitrogenspecies(RONS),whichcaninducecelldeathincancercells,whilehealthycellsaremoreresistanttoRONS.Furthermore,theuseofplasmaforcancertreatmentisnon-invasiveandrelativelypainless,makingitanattractiveoptionforpatients.

Onepromisingplasma-basedtreatmentforcancerisplasma-activatedwater(PAW).PAWiscreatedbyexposingdistilledwatertoplasma,whichresultsintheproductionofRONSandotherreactivespecies.StudieshaveshownthatPAWiseffectiveinkillingcancercellsinvitro,andisalsonon-toxictohealthycells.Furthermore,PAWhasbeenshowntohaveanti-inflammatoryeffects,whichmayhelptoreducethesideeffectsofchemotherapyandothercancertreatments.

Anotherareaofresearchinplasmatechnologyisthedevelopmentofplasma-basedmaterialsprocessingtechniques.Plasmacanbeusedtodepositthinfilmsandcoatingsontoavarietyofmaterials,andcanalsobeusedforsurfacemodificationandetching.Thesetechniqueshavenumerousapplicationsinindustriessuchaselectronics,aerospace,andenergy.

Plasma-basedmaterialsprocessinghasthepotentialtoofferseveraladvantagesovertraditionaltechniques,includinghigherprecision,lowercost,andreducedenvironmentalimpact.Forexample,plasma-basedtechniquescanbeusedtodepositthinfilmsontocomplexshapesandsurfaces,whichisdifficulttoachieveusingtraditionaltechniques.Additionally,plasma-basedtechniquescanbeusedtodepositcoatingsthataremorewear-resistantandcorrosion-resistantthantraditionalcoatings.

Inconclusion,plasmatechnologyisarapidlydevelopingfieldwithnumerouspotentialapplicationsinareassuchashealthcare,materialsprocessing,andenvironmentalrem