統(tǒng)一坐標(biāo)系下多介質(zhì)流體力學(xué)計(jì)算方法研究.pdf

1、中國(guó)工程物理研究院博士學(xué)位論文統(tǒng)一坐標(biāo)系下多介質(zhì)流體力學(xué)計(jì)算方法研究姓名：賈鵬彥申請(qǐng)學(xué)位級(jí)別：博士專業(yè)：應(yīng)用數(shù)學(xué)指導(dǎo)教師：江松20050501AbstractRecentlyHuiintroducedasocalledunifiedcoordinatesystemforcompressiblesinglefluidcomputations，Inthissystem，theflowvariablesareconsideredtobefun

2、ctionsoftimeandofsomepermanentidentificationofpseudo—particleswhichmovewithvelocityhq，qbeingthevelocityoffluidparticlesItincludestheEuleriancoordinatesasspecialcasewhenh=0andtheLagrangianwhenh=1Fortwo—dimensionalinviscid

3、flowthefleefunctionhischosensoaStopreservegridanglesThisresultsinacoordinatesystemwhichavoidsexcessivenumerica【diffusionacrossslipIinesinEuleriancoordinatesandavoidsseveregriddeformationinLagrangiancoordinates，yetitretai

4、nssharpresolutionofsIiplinesInthedissertation，weextendtwo—dimensionalsingle—fluidcomputationstomuttimaterialfluidcomputationsintheunifiedcoordinatesystem，Wediscusstheformandhyperbolicityofthe，一basedextendedEulerequations

5、intheunifiedcoordinate，andgivethesolutiontotheRiemannproblemforthe1DextendedEulerequationsobtainedfromthe2DextendedEulerequationsafterdimensionalsplittingThe2DextendedEulerequationsarenumericallysolvedusingtheGodunovsche

6、mewithMUSCLupdateThenumericaltestsshowtheadvantagesoftheunifiedcoordinateMoreoverweuseamovingmeshmethodotherthanpreservinggridanglesfordeterminationofhNumericalresultsshowgoodefficiencyandaccuracyofthemethodInthelatterpa

7、rtofthedissertation，wegivetheJacobianmatrix，eigenvaluesandcorrespondingeigenvectorsforthe1一DextendedEulerequationsintheunifiedcoordinate，andsolvetheequationsapplyingasecond—orderaccurate，two—stepTVDschemeTheschemedoesnot

8、necessitatethecharacteristicdecompositionsoftheusualTVDschemesAfewnumericalresultsshowsimplicityandpracticabilityofthescheme，andshowtheadvantagesoftheunifiedcoordinateKeyWords：Unifiedcoordinate，multimaterialflow，extended