简介:orthotropic与为平凡高度的温度参数的组成的关系--力量在biaxial压缩下面的高效的水泥(HSHPC)被开发。它基于为包括伪=蟽2在7不同压力比率在HSHPC的二个力量层次描绘力量和变丑行为执行的实验:蟽3=0.00:?1,?0.20:?1,?0.30:?1,?0.40:?1,?0.50:?1,?0.75:?1,?1.00:?1在到20,200,300,400,500和600掳C的正常、高的温度的暴露以后,并且用一台大静电干扰动态的真triaxial机器。biaxial测试在100公里脳上被执行100公里脳100公里立方的标本,和减少磨擦的垫被使用为压缩装载飞机与甘油中立者由塑料膜的三层组成。基于试验性的结果,HSHPC标本的失败模式被描述。主要静态的压缩力量,在山峰应力的紧张和压力紧张曲线被测量;并且他们上的温度和压力比率的inuence也被分析。试验性的结果证明在到高温度的暴露以后的平凡HSHPC的单轴的压缩力量不随温度的增加戏剧性地减少。到它的单轴的压缩力量的biaxial的比率在暴露以后取决于压力比率和HSHPC的易碎物僵硬到不同温度层次。从理论模型和试验性的数据获得的压力紧张结果的比较显示好同意。
简介:Inthepreviouspapers,ahighperformancesparsestaticsolverwithtwo-levelunrollingbasedonacell-sparsestorageschemewasreported.Althoughthesolverreachesquiteahighefficiencyforabigpercentageoffiniteelementanalysisbenchmarktests,theMFLOPS(millionfloatingoperationspersecond)ofLDLTfactorizationofbenchmarktestsvaryonaDellPentiumⅣ850MHzmachinefrom100to456dependingontheaveragesizeofthesuper-equations,i.e.,ontheaveragedepthofunrolling.Inthispaper,anewsparsestaticsolverwithtwo-levelunrollingthatemploystheconceptofmaster-equationsandsearchesforanappropriatedepthsofunrollingisproposed.ThenewsolverprovideshigherMFLOPSforLDLTfactorizationofbenchmarktests,andthereforespeedsupthesolutionprocess.
简介:Thetransientthermalresponseofathickorthotropichollowcylinderwithfinitelengthisstudiedbyahighordershelltheory.Theradialandaxialdisplacementsareassumedtohavequadraticandcubicvariationsthroughthethickness,respectively.Itisimportantthattheradialstressisapproximatedbyacubicexpansionsatisfyingtheboundaryconditionsattheinnerandoutersurfaces,andthecorrespondingstrainshouldbeleast-squarescompatiblewiththestrainderivedfromthestrain-displacementrelation.Theequationsofmotionarederivedfromtheintegrationoftheequilibriumequationsofstresses,whicharesolvedbypreciseintegrationmethod(PIM).Numericalresultsareobtained,andcomparedwithFEsimulationsanddynamicthermo-elasticitysolutions,whichindicatesthatthehighordershelltheoryiscapableofpredictingthetransientthermalresponseofanorthotropic(orisotropic)thickhollowcylinderefficiently,andforthedetonationtubeofactualpulsedetonationengines(PDE)heatedcontinuously,thethermalstresseswillbecometoolargetobeneglected,whicharenotlikethoseintheonetimeexperimentswithveryshorttime.
简介:Toconsidertheanisotropicdamageinfatigue,animprovedboom-panelmodelispresentedtosimulatearepresentativevolumeelement(RVE)intheframeworkofcontinuumdamagemechanics.TheanisotropicdamagestateoftheRVEisdescribedbythecontinuityextentsofboomsandpanels,whosedamageevolutionsareassumedtobeisotropic.Thenumericalimplementationisproposedonthebasisofdamagemechanicsandthefiniteelementmethod.Finally,theapproachisappliedtothefatiguelifepredictionof2A12-T4aluminiumalloyspecimenundercyclicloadingoftension-torsion.Theresultsindicateagoodagreementwiththeexperimentaldata.