文献翻译-电磁探伤无损检测方面的一种可能的实际传感器超材料

附录一外文原稿AKindofPotentialPracticalSensorsofMetamaterialinElectromagneticFlawNondestructiveTestingAbstract：Wepresentanewkindofmethodofelectromagneticflawnondestructivetestingwithcoatingofmetamaterialsandsimulationnearelectromagneticfieldpropertyfortestcrack.ThesimulationofimprovingaNondestructivetesting(NDT)probeelectromagneticradiantpropertybyMetamatrials(MMs)coveringatinycurrentelementisinvestigatedandanalyzedusingAnsoftHFSSbasedonfiniteelementmethod(FEM),whichpermittivityandpermeabilityarenegative.Electromagneticmodel:IdealMMsballshellwithinnerradiusof1mmandouterradiusvariation,andtheshellsrelativepermittivityandrelativepermeabilityareall3.0,dielectriclosstangentandmagneticlosstangentareall0.1;andexcitingcurrentelementlengthiswith0.3mm,diameter0.2mm,value1mAatfrequency10GHz;andsimulationiswithradiationboundaryconditions.Thesimulatingnearelectromagneticfieldvarietywithratioofinnerradiusandoutradius,andsonearorlocalfieldofMMssensoronasurfacecrack,aswellascomparingnearfieldvalueofsensorwithcoatingcommonmaterialarefinished.ResultscanbeseenthatMMsfilmsensornearelectromagneticfieldandradiationpropertiesareobviouslybetterthanothertwokindsofstructureswithoutcoatingmediumandcoatingwithcommonmedium,andMetamaterialmaybeopenedoutsomenewkindsofsensorsinelectromagneticflawnondestructivetestingforpotentialpracticalapplicationsinfuture.Keywords:Metamaterial,Nondestructive,Flaw,AnsoftHFSSSoftware,Sensor1.IntroductionIn1967,Veselagotheoreticallyconsideredahomogeneousisotropicelectromagneticmaterialinwhichbothpermittivityandpermeabilitywereassumedtohavenegativerealvalues.SincetheE,HfieldsandthewavevectorkofapropagatingplaneEMwaveformaleft-handedsysteminthesematerials,Veselagoreferredtothemas“left-handed”media,ormetamaterialmedia1-3.Insuchamedium,heconcluded,thedirectionofthePoyntingvectorofamonochromaticplanewaveisoppositetothatofitsphasevelocity.Itsuggeststhatthisisotropicmediumsupportsbackward-wavepropagationanditsrefractiveindexcanberegardednegative.Sincethesematerialswerenotavailableuntilrecently,theinterestingconceptofnegativerefraction,anditsvariouselectromagneticandopticalconsequences,suggestedbyVeselago,hadreceivedlittleattention.ThiswasuntilSmithetal.4,inspiredbytheworkofPendryetal.3,5constructedacomposite“medium”inthemicrowaveregimebyarrangingperiodicarraysofsmallmetallicwiresandsplit-ringresonators4,6-9anddemonstratedtheanomalousrefractionattheboundaryofthismedium,whichistheresultofnegativerefractioninthisartificialmedium8.Metamaterialsarebroadlydefinedasartificialeffectivelyhomogeneouselectromagneticstructureswithunusualpropertiesnotreadilyavailableinnature.Thisopenedthefieldofcompositematerialsormetamaterialsformicrowavesandopticalapplications.SincetheideaproposedbyVictorVeselagoin1968,theavailabilityofsuchamaterialistakenupnowadaysandextended10-21.Inthispaper,wepresentanewkindofsensorofelectromagneticflawnondestructivetestingwithcoatingofmetamaterialandthenapplyittosimulatenearelectromagneticfieldpropertyfortestcrack.Ouraimistofindoutsomeapplicationofmetamaterialcoveringinsensorthroughbetterfielddesign,andthismethodcangreatlyimprovethenearelectromagneticfieldandradiationpropertiesofthetransducer.2.SplitRingResonators(SRRs)Doublesplitringresonator(SRR)isacommonkindofmetamaterialcell,andconductivestructureinwhichthecapacitancebetweenthetworingsbalancesitsinductance,Figure1.Atime-varyingmagneticfieldappliedperpendiculartotheringssurfaceinducescurrentswhichindependenceontheresonantpropertiesofthestructure,produceamagneticfieldthatmayeitheropposeorenhancetheincidentfield,thusresultinginpositiveornegativeeffective.Foracirculardoublesplitringresonatorinvacuumandwithanegligiblethickness,thefollowingapproximateexpressionisvalid22:where,aistheunitcelllength,andiselectricalconductance.Itbecomesnegativefor0mpm,where0mistheresonantfrequency(forwhicheff);pmisthemagneticplasmafrequency(forwhicheff0).Usually,thereisanarrowfrequencyrangewheretheeff0.Thinmetallicwiresweredescribedasoneoftheearlieststructureswithnegativepermittivity,andthemediawiththeembeddedthinmetallicwirescanbeasartificialdielectricsformicrowaveapplications,Figure2.Thestructurewith0describedbyPendryconsistsofasquarematrixofinfinitelylongparallelthinmetalwiresembeddedindielectricmedium.Inthesituation,themediumisairorvacuum,andtheradiusofasinglewireisverythinnerthanthedistancebetweentwowires,thatisra,theeffectivedielectricpermittivitycanbewrittenasfollow23:where,pistheplasmafrequencyforthelongitudinalplasmamode.Clearly,itbecomesnegativeforp.3.MetamaterialSensorSimulationSimulationofimprovingtheNondestructivetesting(NDT)transducerelectromagneticradiantpropertybyMetamatrials(MMs)coveringatinycurrentelementisinvestigatedandanalyzedusingAnsoftHFSSbasedonfiniteelementmethod(FEM),whichpermittivityandrelativepermeabilityarenegative.3.1.ElectromagneticModelandAssigningMaterialsTheidealMMsballshellfilmiswithinnerradiusof1mmandouterradiusvariation,andtheshellsrelativepermittivityandrelativepermeabilityareall3.0,dielosstangentandmagneticlosstangentareall.SelectingtheSolutionTypeChoosetheDrivenModalsolutiontypewhenwewantHFSStocalculatethemodal-basedS-parametersofpassive,high-frequencystructuressuchasmicrostrips,waveguides,sensors,andtransmissionlines.TheS-matrixsolutionswillbeexpressedintermsoftheincidentandreflectedpowersofwaveguidemodes.3.3.AssigningBoundariesAssigningBoundariesandAssigningExcitationsForDrivenModal,aradiationboundaryisusedtosimulateanopenproblemthatallowswavestoradiateinfinitelyfarintospace,suchasantennadesigns.HFSSabsorbsthewaveattheradiationboundary,essentiallyballooningtheboundaryinfinitelyfarawayfromthestructure.Aradiationsurfacedoesnothavetobespherecal,butitmustbeexposedtothebackground,convexwithregardtotheradiationsource,andlocatedatleastaquarterwavelengthsfromtheradiatingsource.Insomecasestheradiationboundarymaybelocatedcloserthanone-quarterwavelength,suchasportionsoftheradiationboundarywherelittleradiatedenergyisexpected.Here,simulationiswithradiationboFigure3.ExcitationsinHFSSareusedtospecifythesourcesofelectromagneticfieldsandcharges,currents,orvoltagesonobjectsorsurfacesinthedesign.WemayassignthecurrentsourceofexcitationstoaDrivenModalsolutiontypeHFSSdesign,andexcitingcurrentelementlengthiswith0.3mm,diameter0.2mm,value1mAatfrequencyof10GHz.4.RunningSimulationsandConclusionsAfterspecifyhowHFSSistocomputethesolution,webeginthesolutionprocess.Adaptivesolution,maximumnumberof15,andmaximumdeltaenergy0.08areselectedforsolutionsetup,wegetsomeresultsasfollowing:ForthreekindsofstatesofasensorwithcoatingMMs,thosearecoatingcommonmediumandwithoutcoating,simulatingnearelectromagneticfieldvarietywithratioofinnerradiusandoutradius,seeFigure4.Nearfieldisthatoneitsdistancelessthan20mmfromexcitingsourcepoint.SupposetestanaluminumworkpiecewithsurfacecrackbytheMMssensorwithr1/r2=0.5,cracklength6mm,width1mm,anddepth0.1mm,thenearfieldaroundcrackflawseeFigure5;andcomparingtonearfieldvalueofprobewithcoatingcommonmaterialseeFigure6.ResultscanbeseenfromFigure4thatforMMsfilmsensor,nearelectromagneticfieldpropertyisobviouslybetterthanothertwokindsofstructureswithoutcoatingmediumandcoatingwithcommonmedium,andnearfieldvalueisvarietyofratioinnerradiusandoutradius.Whenr1/r2=0.5andnoload,nearandlocalfieldofMMssensorcanreachto10dB,butonly21dBforsensorwithcoatingcommonmedium,and22dBforsensorwithoutcoatinganymedium.WegetfromFigure6thatnearfieldofaMMssensorishigherabout30dBthanoneoftransducercoatingcommonmediumwhenr1/r2=0.5andwithload.Similarly,radiationpowerofMMssensorcanreachto53dB,butonly74dBforsensorwithcoatingcom-monmedium,and75dBforsensorwithoutcoatinganymedium.MMssensorishigherabout20dBthanoneoftransducercoatingcommonmedium.Nearfieldandra-diationpowerarebothimportantpropertiesofasensor.Fromaboveresults,weknowthatMMsfilmsensorisexcellentfornearelectromagneticfieldandradiationproperties.Sosomemetamaterialnondestructiveelectromagneticsensorsincludingsoundwavetransducermaybeopenedoutforpotentialpracticalapplicationsinfuture.5.References1V.G.Veselago,“TheElectrodynamicsofSubstanceswithSimultaneouslyNegativeValuesofand,”SovietPhys2V.G.Veselago,“TheElectrodynamicsofSubstanceswithSimultaneouslyNegativeValuesofand,”UspekhiFizicheskikhNauk,Vol.92,1967,pp.517-526.3J.B.Pendry,A.J.Holden,D.J.Robbins,etal.,“Low-FrequencyPlasmonsinThinWireStructures,”JournalofPhysicsCondensedMatter,Vol.10,No.22,1998,pp.4785-4809.4D.R.Smith,W.J.Padilla,D.C.Vier,etal.,“CompositeMediumwithSimultaneouslyNegativePermeabilityandPermittivity,”PhysicalReviewLetters,Vol.84,No.18,May2000,pp.4184-4187.5J.B.Pendry,A.J.Holden,D.J.Robbins,etal.,“MagnetismfromConductorsandEnhancedNonlinearPhenomena,”IEEETransactionsonMicrowaveTheoryandTechniques,Vol.47,No.11,1999,pp.2075-2081.6D.R.SmithandN.Kroll,“NegativeRefractiveIndexinLeft-HandedMaterials,”PhysicalReviewLetters,Vol.85,No.14,2000,pp.2933-2936.7R.A.Shelby,D.R.Smith,S.C.Nemat-Nasser,etal.,“MicrowaveTransmissionthroughaTwo-Dimensional,Isotropic,Left-HandedMetamaterial,”AppliedPhysicsLetters,Vol.78,No.4,2001,pp.489-491.8A.Shelby,D.R.SmithandS.Schultz,“ExperimentalVerificationofaNegativeIndexofRefraction,”Science,Vol.292,No.5514,2001,pp.77-79.9N.EnghetaandR.W.Ziolkowski,“APositiveFutureforDouble-NegativeMetamaterials,”IEEETransactionsonMicrowaveTheoryandTechniques,Vol.53,No.4,2005,pp.1535-1556.10S.Enoch,G.Tayeb,P.Sabouroux,N.Guerin,etal.,“AMetamaterialforDirectiveEmission,”PhysicalReviewLetters,Vol.89,No.21,2002,ArticleID:213902.11B.Li,B.WuandC.-H.Liang,“StudyonHignGainCircularWaveguideArrayAntennawithMetamaterialStructure,”ProgressinElectromagneticsResearch,Vol.60,2006,pp.207-219.12A.-K.Hamid,“AxiallySlottedAntennaonaCircularorEllipticCylinderCoatedwithMetamaterials,”ProgressinElectromagneticsResearch,Vol.51,2005,pp.329-icsUspekhi,Vol.10,No.4,1968,pp.509-514.341.13J.BPendry,A.J.Holden,W.J.Stewart,etal.,“ExtremelyLowFrequencyPlasmonsinMetallicMicrostructures,”PhysicalReviewLetters,Vol.76,No.25,1996,pp.4773-4776.14C.G.Parazzoli,R.B.Greegor,J.A.Nielsen,etal.,“PerformanceofaNegativeIndexofRefractionLens,”PhysicalReviewLetters,Vol.84,No.17,2004,pp.3232-3234.15J.B.PendryandD.R.Smith,“ReversingLightwithNegativeRefraction,”PhysicsToday,Vol.57,No.6,2004,pp.37-43.16Z.X.XuandW.G.Lin,“ControllableAbsorbingStructureofMetamaterialatMicrowave,”ProgressinElectromagneticsResearch,Vol.69,2007,pp.117-125.附录二外文原稿翻译电磁探伤无损检测方面的一种可能的实际传感器超材料摘要：我们提出了一种新的电磁无损检测方法，通过超材料涂层和仿真靠近电磁场属性来检测裂纹。覆盖细小的电流元素的超材料（MMS）来提高无损检测（NDT）探头的电磁辐射属性的仿真，使用基于有限元法（FEM）中的AnsoftHFSS调查和分析，它的负介电常数和磁导率是负的。电磁模型：理想的MMs球壳内径是1毫米，外径是变化的，和壳的相对介电常数和相对磁导率都是-3.0，介电损耗角正切值和磁损耗角正切值都是0.1，并且与涂层为普通材料做的球传感器的近领域的值相比较，当频率为10GHz时，该模型的励磁电流元长度是0.3毫米，其直径为0.2毫米，值为1毫安。电磁场附近的各种内半径和外半径的比率的仿真，和MMs传感器表面上的裂纹如此接近或本区域，相对于带涂层的普通材料的传感器附近区域的值是完成的。结果很明显：MMs薄膜传感器近电磁场和辐射特性明显优于无涂层的介质和涂层与普通介质这两种结构传感器，在将来，超材料将打开一些新的各种传感器在电磁缺陷无损检测方面的潜在的实际应用。关键词：超材料，无损探伤，缺陷，AnsoftHFSS软件，传感器1介绍在1967年，韦谢拉戈理论上认为一个均匀各向同性电磁材料的介电常数和磁导率被假定为具有负实值。自从在这些材料中E，H场和波矢k传播的平面电磁波形成一个左手系统以来，韦谢拉戈称他们为“左撇子”的介质或超材料介质1-3。他的结论是，在这样的介质中，一个单色平面波的坡印廷矢量的方向与它的相位速度是相反的。它表明，这个各向同性介质支持的向后波的传播，它的折射率可视为负。由于这些材料是不可用的，直到最近，这个有趣的概念负折射，和它的各种电磁和光学结论才得到关注，韦谢拉戈说到。这是直到Smith等人4，受到彭德里等人工作的启发3,5，在微波体系中通过整理小金属导线和开口环谐振器4,6-9周向阵列构建了一个复合的“介质”，并陈述了此介质的边界处的异常折射，这是在该人工介质的负折射的结果8。超材料被广泛定义为人工有效均匀的电磁结构，在自然界其不同寻常的特性是无法找到的。这打开了复合材料或微波和光学应用的超材料领域。自从韦谢拉戈1968年提出的想法以来，这种材料的可用性从现在开始并扩大10-21。在本文中，我们提出了一种新的带涂层的超材料电磁探伤无损检测传感器，然后将它应用到靠近电磁场附近的裂纹检测。我们的目的是通过更好的现场设计找出传感器方面的一些超材料覆盖的应用，这种方法可以大大提高传感器近磁场和辐射特性。2开口谐振环（谐振环）双开口谐振环（SRR）是一种常见的超材料电池，如图1所示，导电结构，其中两环之间的电容平衡其电感，。一种随时间变化的磁场垂直于环表面诱导电流，该电流依赖于结构的共振特性，产生既可以减少也可以增强入射场的磁场，从而导致在正或负的有效值。对于一个在真空中和厚度可以忽略不计的圆形双开口环谐振器，下面的近似式是适用的22：其中，a是单位导体的长度，是电导。它变成负有0mpm，其中0m谐振频率（当eff）;pm的是磁场的等离子体频率（当eff0）。一般，有一个eff0窄的频率范围。薄金属线是具有负的介电常数的最早的结构之一，并与嵌入的细金属线的介质可以作为人工电介质微波应用，如图2所示。彭德里所描述0的结构由嵌入在电介质中的无限长的平行细金属线的正方形矩阵构成。在这种情况下，介质是空气或真空，单线的半径比两条导线之间的距离更薄，即为有效介电常数ra，可写为如下式23：其中，p是等离子体模式的等离子体频率。显然，它P时，变成负数。3超材料传感器仿真由覆盖细小的电流元素的超材料（MMS）来提高无损检测（NDT）探头的电磁辐射属性的仿真，并使用基于有限元法（FEM）中的AnsoftHFSS调查和分析，知道它的负介电常数和磁导率都是负的。3.1电磁模型和材料分配理想的MMS球壳是内径为1毫米，而外半径是变化的，和壳的相对介电常数和相对磁导率都是-3.0，介电损耗角正切值和磁损耗角正切值都是0.1。3.2解决方案类型的选择当我们想用HFSS来计算被动的S-参数，高频率的结构基础模式，如微条，波导，传感器和传输线时，选择驱动模式解决方案类型。S-矩阵解决方案将表示关于事件和反映波导模式的功率。3.3指定边界和激励分配对于驱动模式，辐射边界是用来模拟一个开放的问题，它允许无限远波辐射进入太空，如天线的设计。HFSS在辐射边界吸收波，实质上使边界膨胀远离结构。一个辐射表面不必是球形的，但必须暴露其背景，关于放射源是凸面的，并且到辐射源的距离至少为四分之一波长。在某些情况下，辐射边界可以位于接近四分之一波长处，例如辐射边界的部分，此处预期的辐射能量是最少的。在这里，用辐射边界条件来仿真。见图3。用于指定在HFSS的激发电磁场和费用，电流，或在设计中的物体或表面上的电压。我们可能分配的激励电流源的驱动模态溶液型HFSS设计，励磁电流元素的长度是0.3毫米，直径0.2毫米，在10GHz的频率时值1mA。4运行仿真和结论指定HFSS如何计算的解决方案后，我们开始进行解决过程。解决设置选择自适应的解决方案，最大号码为15，最大的增量能源为0.08，我们得到如下一些结果：涂层为MMs的3种状态的传感器，他们都是普通涂层介质和无涂层，近电磁场各种内径和外径之比的仿真，见图4。近场是从激励源点的距离小于20毫米的场。假设由R1/R2=0.5，裂纹长度6毫米，宽1毫米，深度0.1毫米的MMs传感器测试的铝工件的表面裂纹，近场周围裂纹缺陷见图5；和探针涂层为普通材料的近场值对比见图6。结果从图4中可以看出，对于MMs的薄膜传感器，近电磁场特性明显优于另外两种无涂层的介质和涂层为普通介质