简介：批评转变雷纳兹数字的决心具有为一些设计问题的实际重要性。然而，它不与当前的理论方法是可得到的，并且不得不依靠实验。为超声/极超音速的边界层流动，为决心的试验性的方法也不是可行的。在这份报纸，因此，为为不可压缩的飞机隧道流动的批评转变雷纳兹数字的决心的一个数字方法被建议。测试方法的可行性基本上被瞄准。建议方法被扩大在随后的报纸决定超声/极超音速的边界层流动的批评雷纳兹数字。

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简介：Thepropagationofshockwavesinacellularbarissystematicallystudiedintheframeworkofcontinuumsolidsbyadoptingtwoidealizedmaterialmodels,viz.thedynamicrigid,perfectlyplastic,locking(D-R-PP-L)modelandthedynamicrigid,linearhardeningplastic,locking(D-R-LHP-L)model,bothconsideringtheeffectsofstrain-rateonthematerialproperties.Theshockwavespeedrelevanttothesetwomodelsisderived.ConsiderthecaseofabarmadeofoneofsuchmaterialwithinitiallengthL0andinitialvelocityviimpingingontoarigidtarget.Thevariationsofthestress,strain,particlevelocity,specificinternalenergyacrosstheshockwaveandtheceasedistanceofshockwavearealldeterminedanalytically.Inparticularthe'energyconservationcondition'andthe'kinematicexistencecondition'asproposedbyTanetal.(2005)isre-examined,showingthatthe'energyconservationcondition'andtheconsequent'criticalvelocity',i.e.theshockcanonlybegeneratedandsustainedinR-PP-Lbarswhentheimpactvelocityisabovethiscriticalvelocity,isincorrect.Instead,withelasticdeformation,strain-hardeningandstrain-ratesensitivityofthecellularmaterialsbeingconsidered,itisappropriatetoredefineafirstandasecondcriticalimpactvelocityfortheexistenceandpropagationofshockwavesincellularsolids.StartingfromthebasicrelationsforshockwavepropagatinginD-R-LHP-Lcellularmaterials,anewmethodforinverselydeterminingthedynamicstress-straincurveforcellularmaterialsisproposed.Byusinge.g.acombinationofTaylorbarandHopkinsonpressurebarimpactexperimentaltechnique,thedynamicstress-straincurveofaluminumfoamcouldbedetermined.Finally,itisdemonstratedthatthisnewformulationofshocktheoryinthisone-dimensionalstressstatecanbegeneralizedtoshocksinaone-dimensionalstrainstate,i.e.forthecaseofplateimpactoncellularmaterials,bysimplymakingproperreplacementsoftheelasticandplasticconstant