結構-直角網(wǎng)格下時域有限體積法在計算電磁中的應用研究.pdf

1、分類號：V211密級：學校代碼：10699學號：036056157西北工業(yè)大學碩士學位論文(學位研究生)結構／直角網(wǎng)格下時域有限體積法在計算電磁中的應用研究作者陳剛指導教師高正紅教授學科(專業(yè))飛行器設計西北工業(yè)大學航空學院2006年3月西安AbstractBasedontheconceptofaerodynamicandstealthsynthesisdesignforaircraftandmissileconfigurations，

2、acharacteristicbased，F(xiàn)initeVolumemethodinTimeDomain(FVTD)，whichstemsfromthetechniquesofComputationalFluidDynamics(CFD)hasbeenappliedtocomputationalelectromagnetism(CEM)graduallyduringtherecentdecadesGroundedonplentyoflit

3、eratures，thisthesishasexploredcellcentered，electromagneticvariablescollocatedFVTDalgorithmswhileusingstructuredandunstructuredgridssuccessivelyInthisthesis，asolverforsimulationofpropagationofplanarelectromagneticwaveinfr

4、eeormulti—mediumspaceinIDcasesandasolverforscatteringproblemsin2Deasesusingstructuredgrids，andasolverforscatteringproblemsin3DcasesusingadaptiveCartesiangridsaredevelopedinorderTherelativelyhighorderprecisionofthesolvers

5、hasbeenvalidatedbyquantityofnumericaItestcases1nthestructuredFVTDalgorithmafter1eftandrightstatevariableshavebeenobtainedusingtheVanLeer’sMUSCLschemefluxformulationoneellInterfaceisobtainedbyusingStegerWarmingfluxvectors

6、plittingorapproximateRiemannsolutionbothofwhicharepresentedsuccessivelyanddemonstratedessantialequalbynumericalresults0neefluxcalculationareaccomplishedthesemidiscretizationequationsarecastintoordinarydi疵rentiaiequations

7、whichcanbesolvedbyseverelnumericalmethodsincludingthetwoandfourstepsRunge—KuttaalgorithmadoptedinIDand2DeasesrespectivelyinthisthesisTos“dythedissipationanddispersioncharacteristicsofMUSCLschemeandtwo—fourstepsRange—Kutt

8、aintegrationmentionedabove，stabilltyanalysisusingModifiedPDEandFouriermethodsisperformedfirstlyInthenextchapterthestructuredalgorithmisappliedtosimulatethepropagationofplanarelectromagneticwaveinfreeormulti—mediumspaceTh

9、estudyofimpactofdifferentMUSCLschemes，gridresolution，CFLnumbersande：dformsonaccuracyanddissipativeanddispersivefeaturesisperformedandtherangesofvalueforcorrespondingparametersarediscussedandsuggestedbasedontheworkdoneint

10、hispartFoundedontheformerlywork，scatteringproblemsofseveral2DperfectelectricalconductorsincludingcylinderandNACA0012airfoilalesolvedThefactthatcomputationalresultsofsurfaceinducedelectriccurrentandbiostaticRadarCrossSect

11、ion(RCS)agreequitewellwiththeoryvaluesorresultsfromreferencesdemonstratesthattheFVTDfsahighaccuratemethodforcomputationalelectromagneticsandthesolverusing2Dstructuredgridsdevelopediscapableforthescatteringproblemsoverqui

12、tewiderangefromlowtohighfrequencyandalsoapplicabletopracticalshapeinengineeringMeanwhile，throu【ghthediscussionofthenumericalresultsofcylindertheimpactsoftheparametersinvolvedontheresultsareinvestigatedandtheallowablevalu

13、erangesoftheparametersarealsosuggestedTheunstructuredFVTDalgorithmadoptedisstillcastintheformofsemi—discretizationAfterleftandrightstatevariableshavebeenobtainedbythereconstructionmethod，approximateRiemmanSolutionisintro