涡电流金属管检测系统

《涡电流金属管检测系统》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。

1、EddyCurrent簡介:圓柱體有外加的時變電磁場穿過它時'由楞次定律可知在此圓柱體的內部會感應出一電流以產生反抗外加電磁場的變動。此感應電流即謂之”渦電流(EddyCurrent)°mountingrodscrewstM4J641ariablc(nipMagnetaluminumrod(3)aluminumpaddlesFA1-8642AMagneticForvcAcccsson利用渦電流效應我們可以做非破壞性檢測(Non-Distructive-Testing,NDT)ACVoltmeteraddcumpohtjntEddyCurrentsFlow

2、inginthematerialwillgeneratetheirawn11secondaryMmagneticfieldwhichwillopposethecoll'sHprImaryHmagneticfield

3、與薄膜厚度等。另外，產生的渦電流也有SkinEffect，隨深度以指數遞減（利用此原理可檢測缺陷深度與薄膜厚度）。EddyCurrentDepthofPenetrationACAC£do>oStandardDepthofPenetration、(skindepth)1/eor3^ofsurfacedensityEddyCurrentDensityEddyCurrentDensityLowFrequencyLowConductivityLowPermeabilityHighFrequencyHighConductivityHighPermeability問題

4、敘述:一半徑爲0.03，高0」的金屬圓柱體，其CF=3・7幺7。今有一環狀電流圍繞此金柱體'此環狀線圈之中心點距金屬圓柱體之中心點爲0.05，而線圈本身的直徑爲0.02，其上有外加交流電1000A（均方根値），孵爲lOOHzo請畫出Totalcurrentdensity,phicomponent與magneticfluxdensityB之分佈圖。步驟一・選擇Model由於本問題有axialsymmetry，即解答有phi對稱‘且有z軸（即r=0）對稱，所以NewModelNavigatorModelLibraryUserModelsSettingsSpac

5、edimension:Axialsymmetry(2D)4FEMLABl±ll±ll±l0

6、ElectromagneticsModule

7、Acoustics

8、DiffusionqElectromagnetics♦♦♦♦ConductiveMediaDCElectrostaticsMagnetostaticsACPowerElectromagneticsElectromagneticsIFluidDynamicsIHeatTransferIStructuralMechanicsDescription:Quasi-staticsofconducting,mag

9、netic,anddielectricmaterialswithelectriccurrentsflowingintheangulardirection.Time-harmonicanalysis.Element:Dependentvariables:Applicationmodename:MultiphysicsCancel步驟二、參輸入與設定CancelApply)[ApplicationScalarVariables（記得frequency要改變）步驟三、繪製幾何GEOMETRYMODELINGNowdefinethestructuresgeomet

10、ryusingtheCADtoolsbuiltintoFEMLAB.1Startbydrawingacirclethatrepresentsthecoil.Todoso,selectgototheDrawmenuandthenselectDrawObjectsandthenEllipse/Circle(Centered):alternately,gototheDrawtoolbarontheleftoftheMainaxesareaandclicktheDrawCenteredEllipsebutton・Clicktherightmousebuttonat

11、(0.05,0)andmovethecursorto(0.05,0