简介：Thispaperaimstoinvestigatethehydrodynamicbehaviorofatensionlegplatform(TLP)whenthetendonconnectionanglesarevariedat90°,70°,50°,and30°.ThreedifferenttypesofloadingconditionsareappliedtotheTLP.Conditionsinclude100-yearhurricanestormperiod,regularwavesandnoloading.TheTLPdisplayedmajorresponseinthepitchdegreeoffreedom.Amaximumreductionof14%inpitchrotationisachievedwhen100-yearhurricanestormconditionsareappliedtotheTLP.Thisoccurredin0°loadingsat30°tendonconnectionangleascomparedto90°tendonconnectionangle.Reductioninpitchrotationisalsoachievedintheregularwaveloadings.Amaximumof9%inpitchrotationisachievedduring0°waveloadingat30°tendonconnectionangleascomparedto90°.Whenthetendonconnectionangleisreducedfrom90°to30°,thenaturalfrequencyoftheTLPincreasedbothinpitchandyawdegreesoffreedomby2.55%and2.40%,respectively.

简介：实验研究复杂波形结构引起平面界面变形和反射激波冲击下的R-M不稳定性的问题.在竖直激波管中生成稳定的N2/SF6平面界面,激波在圆柱绕射后,冲击平面界面,由此研究复杂激波引起的界面变形.平面激波在圆柱绕射后的流场,演化成具有初始入射波、三波点、弯曲反射波、Mach波和Mach反射产生的滑移线等复杂结构.研究复杂结构激波对界面的作用,对认识界面扰动的生成具有较大帮助.绕柱激波冲击后,平面界面仅在两对滑移线内部发生变形.绕柱激波冲击界面后,两对滑移线将界面分成＂内界面＂和＂外界面＂,界面变形形态同滑移线和界面相交位置相关.反射激波二次冲击下,界面扰动的增长与Jacobs-Sheeley涡量模型较吻合.

简介：Head-oncollisionbetweentwohydroelasticsolitarywavespropagatingatthesurfaceofanincompressibleandidealfluidcoveredbyathinicesheetisanalyticallystudiedbymeansofasingularperturbationmethod.TheicesheetisrepresentedbythePlotnikov-TolandmodelwiththehelpofthespecialCosserattheoryofhyperelasticshellsandtheKirchhoff-Loveplatetheory,whichyieldsthenonlinearandconservativeexpressionforthebendingforces.TheshallowwaterassumptionistakenforthefluidmotionwiththeBoussinesqapproximation.TheresultinggoverningequationsaresolvedasymptoticallywiththeaidofthePoincar-Lighthill-Kuomethod,andthesolutionsuptothethirdorderareexplicitlypresented.Itisobservedthatsolitarywavesaftercollisiondonotchangetheirshapesandamplitudes.Thewaveprofileissymmetricbeforecollision,anditbecomes,aftercollision,unsymmetricandtitledbackwardinthedirectionofwavepropagation.Thewaveprofilesignificantlyreducesduetogreaterimpactsofelasticplateandsurfacetension.Agraphicalcomparisonispresentedwithpublishedresults,andthegraphicalcomparisonbetweenlinearandnonlinearelasticplatemodelsisalsoshownasaspecialcaseofourstudy.

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简介：Thebubblesriseupandburstatthefreesurfaceisacomplextwo-phaseprocess.AfreeenergylatticeBoltzmannmethod(LBM)modelisadoptedinthispapertostudythisphenomenon.Theinterfacecapturingtechnique[Zhengetal.,2006]isusedtodealwiththehighdensityratioproblem.TheLaplacelawandtheair-waterinterfacecapturingabilityarevalidatedforthemultiphasemodel.Theinteractionbetweenthesinglebubbleormultiplebubblesandthefreesurfacearestudiedbythemultiphasemodel.Theforceactingonthebubbleandtheevolutionofthefreesurfaceisstudied.Meanwhile,effectoftheinitialdistancebetweentwoadjacentbubblesoninteractioneffectsofmultiplebubblesisinvestigatedaswell.

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简介：在不同工况下,旋转爆震波能够以单波、双波、多波模式进行传播.但在同一工况下,是否存在不同模式的稳定传播爆震波还有待进一步研究.基于Euler方程,耦合氢气/空气的有限化学反应速率模型,并采用高分辨率的5阶有限差分格式WENO-PPM5离散对流项,对三维旋转爆震波进行了数值模拟.计算结果表明,在同一特定工况下,旋转爆震波能够以两种不同的传播模式稳定传播,即单波模式和双波模式.详细地对比了两种传播模式下的流场特征、爆震波传播特性、推力性能等.在同一工况下,两种传播模式的爆震波周向传播速度相差不多,但双波模式的频率约为单波模式的2倍;双波模式下质量流量、比冲、推力的平均值均略高于单波模式;且双波模式的可燃混气层高度约为单波模式的1/2,这有助于缩小旋转爆震发动机的长度,使之更加紧凑.