简介：在在机翼附近的接近音速的流动的不稳定的现象在扇子，压缩机片和蝴蝶阀门的流动地里被观察，并且这经常引起象aeroacoustic噪音那样的严重问题，颤动。在蒸汽在主要流动被包含的接近音速或超声的流动，流动的快速的扩大可以产生一个非平衡冷凝作用。然而，在机翼附近的接近音速的内部流动上的非平衡冷凝作用的效果还没令人满意地被澄清了。在现在的学习，圆形的弧片上的自我刺激的冲击波摆动上的潮湿的空气的非平衡冷凝作用的效果数字地被调查。结果证明在有非平衡冷凝作用的情况中，没有非平衡冷凝作用，流动摆动的频率变得比那些小。

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简介：Anumericalmethod,theso-calledmultiplemonopole(MMoP)method,basedonthegeneralizedmultipoletechnique(GMT)isproposedtocalculatethebandstructuresofin-planewavesintwo-dimensionalphononiccrystals,whicharecomposedofarbitrarilyshapedcylindersembeddedinasolidhostmedium.Tofindtheeigenvalues(eigenfrequencies)oftheproblem,besidesthesourcesusedtoexpandthewavefields,anextramonopolesourceisintroducedwhichactsastheexternalexcitation.Byvaryingtheexcitationfrequency,theeigenvaluescanbelocalizedastheextremepointsofanappropriatelychosenfunction.BysweepingthefrequencyrangeofinterestandtheboundaryoftheirreduciblefirstBrillouinzone(FBZ),thebandstructurescanbeobtained.Sometypicalnumericalexampleswithdifferentacousticimpedanceratiosandwithinclusionsofvariousshapesarepresentedtovalidatetheproposedmethod.

简介：Thescatteringproblemofanti-planeshearwavesinafunctionallygradedmaterialstripwithanoff-centercrackisinvestigatedbyuseofSchmidtmethod.Thecrackisverticallytotheedgeofthestrip.ByusingtheFouriertransform,theproblemcanbesolvedwiththehelpofapairofdualintegralequationsthattheunknownvariableisthejumpofthedisplacementacrossthecracksurfaces.Tosolvethedualintegralequations,thejumpofthedisplacementacrossthecracksurfaceswasexpandedinaseriesofJacobipolynomials.Numericalexampleswereprovidedtoshowtheeffectsoftheparameterdescribingthefunctionallygradedmaterials,thepositionofthecrackandthefrequencyoftheincidentwavesuponthestressintensityfactorsofthecrack.

简介：Strongnonlinear,electro-optical,andthermo-opticalpropertiesoflithiumniobate（LN）havegainedmuchattention.However,theimplementationofLiNbO3inrealdevicesisnotatrivialtaskduetodifficultiesinmanufacturingandhandlingthin-filmLN.Inthisstudy,weinvestigateanopticaldevicewheretheBlochsurfacewave（BSW）propagatesonthethin-filmLNtounlockitsproperties.First,accesstotheLNfilmfromair（oropenspace）isimportanttoexploititsproperties.Second,forsustainingtheBSW,one-dimensionalphotoniccrystal（1DPhC）isnecessarytobefabricatedunderthethin-filmLN.Weconsidertwomaterialplatformstorealizesuchadevice:bulkLNandcommercialthin-filmLN.Clearreflectancedipsobservedinfar-fieldmeasurementsdemonstratethepropagationofBSWsontopoftheLNsurfaceofthedesigned1DPhCs.

简介：Inthispaper,thescatteringofharmonicantiplaneshearwavesbytwofinitecracksisstudiedusingthenon-localtheory.TheFouriertransformisappliedandamixedboundaryvalueprob-lemisformulated.Thenasetoftripleintegralequationsissolvedusinganewmethod,namelySchmidt’smethod,ThismethodismoreexactandmorereasonablethanEringen’sforsolvingthiskindofproblem.Theresultofthestressnearthecracktipwasobtained.Contrarytotheclassicalelas-ticitysolution,itisfoundthatnostresssingularityispresentatthecracktip,whichcanexplaintheproblemofmacroscopicandmicroscopicmechanics.

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简介：与浸透的土壤存款的由一条半球的冲积山谷的三维的散布和飞机P波浪的衍射的一个分析解决方案被采用Fourier-Bessel系列扩大技术开发。不同于以前的研究，浸透的土壤存款与单相的有弹性的理论在被模仿，在这篇论文，他们为浸透的多孔的媒介，和一半与Biot的动态理论被模仿空间作为asingle阶段被假定橡皮媒介。更少的频率，发生角度ofP波浪和土壤的孔在半球的冲积山谷的表面排水量放大上扔的尺寸的效果被调查。数字结果证明一条浸透的半球的冲积山谷的存在在表面排水量放大上有许多影响。当与发生ofP波浪评估一条半球的冲积山谷的排水量回答时，与Biot的动态理论模仿土壤存款是更合理的。

简介：这份报纸为高度装载的接近音速的压缩机串联论述对流动分离的重新组织的冲击波的影响的详细数字调查。边界层吸(BLS)被用来控制冲击波的地点和力量，与在49%弦定位的把发成送气音的槽，在的地方只在前缘的冲击波的冲击点是下游的。数字模拟基于NUMECA，一个商业软件，在有第三顺序的空间精确性的以房间为中心的控制卷途径被用来解决3-D的地方在笛卡儿的坐标系统下面的平均Reynolds的海军司烧方程。几个结论能通过数字结果的观察被做。(1)在串联经过的多重冲击波在冲击波下游的吸表面上带了边界层的速度赤字，导致片的吸方面上的严重分开的流动，特别当前面冲击波比震动的其余部分强壮得多时。(2)有小集体流动率的BLS不能有效地改进边界层。来自串联前缘的倾斜的冲击波的冲击点是什么时候，放血了到由BLS的经过冲击波下游，边界层流动极大地被改进。然而，如果BLS集体流动率超过批评价值(1.2%)，冲击波下游的边界层将与吸表面分开。(3)在片中间跨度，压缩机片的空气动力学的表演作为BLS集体流动率增加被改进。最佳BLS是大约1.2%。与基线盒子相比，有1.2%的流动率的BLS增加全部的压力恢复系数12%，并且减少在18%的散开因素和到7的偏差角度吗？

简介：Interfacialinternalwavesinathree-layerdensity-stratifiedfluidareinvestigatedusingasingularperturbationmethod,andthird-orderasymptoticsolutionsofthevelocitypotentialsandthird-orderStokeswavesolutionsoftheassociatedelevationsoftheinterfacialwavesarepresentedbasedonthesmallamplitudewavetheory.Asexpected,thethird-ordersolutionsdescribethethird-ordernonlinearmodificationandthethird-ordernonlinearinteractionsbetweentheinterfacialwaves.Thewavevelocitydependsonnotonlythewavenumberandthedepthofeachlayerbutalsoonthewaveamplitude.

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简介：AnExperimentalinvestigationonthebehaviorandcharacteristicsofinterfacialwavesindownwardinclinedrectangularchannelwasconducted.Theinterfacialwavesweretracedandmeasuredbyusingconductancetechnique.Thewavepatternsweredistingushedanddefined.Thecharacteristicsoftheinterfacialwaves.suchastime-averagedfilmthickness,waveheight,wavepropagationspeed,wavelengthandwavefrequency,weresystematicallyexaminedintermsofgasandliquidsuperficialvolumetricfluxes.Theeffectoftheinclinationandflowchannelgeometryofthetestsectionontheinterfacialwavewasalsoinvestigated.

简介：Ameshlessradialbasisfunction(RBF)collocationmethodbasedontheEringennonlocalelasticitytheoryisdevelopedtocalculatethebandstructuresofternaryandquaternarynanoscalemulti-layeredphononiccrystals(PNCs)withfunctionallygraded(FG)interlayers.Detailedcalculationsareperformedforanti-planetransversewavespropagatinginsuchPNCs.TheinfluencesofFGandhomogeneousinterlayers,componentnumber,nonlocalinterfaceimperfectionsandnanoscalesizeoncut-offfrequencyandbandstructuresareinvestigatedindetail.Numericalresultsshowthatthesefactorshavesignificanteffectsonbandstructuresatthemacroscopicandmicroscopicscales.