多循環(huán)脈沖爆轟發(fā)動機內(nèi)、外流場的實驗和數(shù)值研究.pdf

1、南京理工大學(xué)博士學(xué)位論文多循環(huán)脈沖爆轟發(fā)動機內(nèi)、外流場的實驗和數(shù)值研究姓名：于陸軍申請學(xué)位級別：博士專業(yè)：工程力學(xué)指導(dǎo)教師：范寶春葉經(jīng)方20080701AbstractPulsedDetonationEngine(PDE)isanew—conceptpowerdevice，whichutilizespulseddetonationwavestoproduceforceComparedwithConventionalpropulsiont

2、urbineenginePDEsaremorecompactandreliablebecauseofnorotationalcomponentSince1980s，aseriesofimportantachievementswereachievedinthestudiesoftheexperimentalandnumericalsimulationHowev％theseresearchesseldomconcernedthedynami

3、csstructureoftheexternalflowfiledWhilePDEiswofkin島thedynamicsstructureoftheinternalflowfiledaffectsnledevelopmentoftheexternalflowfieldtheexternalflowfieldiScounteractiveintheinternalflowfieldwhichledtotheinstabilityofth

4、rustandperformance，andtherearegreaterdifferencesofdynamicsmechanismoftheinternalandexternalflowfieldamongmulticyclesSothatresearchesintheseaspectsarebothacademicallyandpracticallysignificantInthispapertheexperimentsonthe

5、processofPDEWereperformedandthepressure—timeprofilesoftheexternalflowfieldwereobtainedMoreoversomevisualizationtestsoftheexternalflowfieldWereimplementedbyusingYA一16hi曲speedshadowgraphimagingsystem，andtheclearsequentials

6、hadowgraphimageswerealsoobtainedintestsInaddition，bysolvingaxisymmetricEulerequationsinconjunctionwiththechemistrynumericalsimulationoftwocyclesofpulsedetonationenginewasperformedandadetailedchemicalmechanismofH202N2syst

7、em，whichincluded19elementreactionsand9species，WasinvolvedAninsituadaptivetabulation(ISAT)methodWasimprovedtoerlhancethecomputationalperformanceofcombustionchemistryFurthermorethecomputationalshadowgraphimageswereplottedb

8、asedonthenumericalresultsandrelevantcomputationalflowimagingmethodsBasedontheexperimentalresults，numericalresultsandcomputationalshadowgraphimages，thedynamiccharacteristicsoftheinternalandexternalflowfieldswereelucidated

9、systematicallyInthispaperafterthedonationwaveventedexternalflowfieldinthefirstcycle，itdecayedintoanonreactivesphericalshockwavefollowedbyhotcombustionproductsAvortexringwasinducedbyBarocliniceffectsandHelmholtzinstabilit

10、iesinthevicinityofthethrusterexitwhichfunctionedasaconvergent／divergentfluidnozzleThecombustionproductsbehindtheshockwaveformedthePrandtlMeyerflowintheexitofthetubeduetotheunderexpansions，andthesuspendedshockoccurredwhic