学科分类
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153 个结果
  • 简介:拿h[m]作为一个弄弯的边的网孔宽度[m](m=1,,d)多角形并且用弱单个的积分的照规则,这份报纸为在弄弯的多角形上解决第一种飞机弹性Dirichlet问题的BIES论述机械照方法,它拥有高精确性O(h3[0])并且低计算复杂性。自从有力量h3的近似错误的multivariateasymptotic扩大[我](i=1,2,,d)被显示出,借助于切开的推测,高精确近似和posteriori估计被获得。[从作者抽象]

  • 标签: 分裂外推算法 线性弹性问题 边界积分方程 求积法
  • 简介:有牛顿重复的一个新decoupled二系结算法为解决描述通过多孔的媒介过滤的液体流动的联合Navier-Stokes/Darcy模型被建议。而且错误估计被给,当时,它证明精确性的一样的顺序能作为在好网孔直接解决系统被完成h=H2。理论分析和数字实验为解决联合问题说明算法的效率。

  • 标签: 牛顿迭代 模型描述 求解 加纳 格法 修改
  • 简介:Wediscusstheincompletesemi-iterativemethod(ISIM)foranapproximatesolutionofalinearfixedpointequationsx=Tx+cwithaboundedlinearoperatorTactingonacomplexBanachspaceXsuchthatitsresolventhasapoleoforderkatthepoint1.SufficientconditionsfortheconvergenceofISIMtoasolutionofx=Tx+c,wherecbelongstotherangespaceof(I-T)k,areestablished.WeshowthattheISIMhasanattractivefeaturethatitisusuallyconvergentevenwhenthespectralradiusoftheoperatorTisgreaterthan1andInd1T≥1.ApplicationsinfiniteMarkovchainisconsideredandillustrativeexamplesarereported,showingtheconvergencerateoftheISIMisveryhigh.

  • 标签: SINGULAR linear operator equation index DRAZIN
  • 简介:Thepurposeofthepaperistoestablishatheoryoftheconstantheatfluxratioacrossthefrozenlayerbasedonthedimensionalanalysisofthesystemequationsdescribingthefreezingprocesses.Ananalyticalmodelisthendeveloped,utilizingthistheory,forsolvingtheplanar,cylindricalandsphericalfreezingproblemswithbothinwardandoutwardfreezing.Asthereisnoexactsolutionavailableforthecylindricalandsphericalfreezingprocesses,thetemperaturedistributionintheplanarsolidificationobtainedfromthemodeliscomparedwiththeexactsolution.Theyareinexcellentagreement.Forthecylindricalandsphericalfreezing,thecompleteinwardsolidificationtimescalculatedbythemodelarecomparedwiththoseobtainedfromreferences.Theresultsareingoodagreement.Thegreatadvantageoftheproposedmodelisitssimplicityandissufficientlyaccurateformostpracticalapplications

  • 标签: analytical PLANAR CYLINDRICAL SPHERICAL solidification theory
  • 简介:在这篇论文,为解决单个延期的二拍子的圆舞连续性Runge-Kutta(TSCRK)方法的一个班微分方程(DDE)被介绍。方法被给的这的数字稳定性的分析。我们考虑二个不同盒子:(ⅰ)τ≥h,(ⅱ)τ

  • 标签: 时滞微分函数 稳定性 连续性 RUNGE-KUTTA方法
  • 简介:一个数字算法为包含与排干和涂层流动联系的第三顺序的平常的微分方程的某些边界价值问题的答案的近似被开发。数字算法获得的近似解决方案用nonpolynomialquintic花键函数发展了由的作者表演比另外的花键和域分解方法生产的那些好。算法在与排干和涂层流动表明途径的实际实用性联系的二个问题上被测试。

  • 标签: 多项式样条 数值算法 三阶边值问题 涂料 排水 三阶常微分方程
  • 简介:Aself-adaptiveprecisealgorithminthetimedomainwasemployedtosolve2-Dnonlinearcoupledheatandmoisturetransferproblems.Byexpandingvariablesatadiscretizedtimeinterval,thevariationsofvariablescanbedescribedmoreprecisely,andanonlinearcoupledinitialandboundaryvalueproblemwasconvertedintoaseriesofrecurrentlinearboundaryvalueproblemswhicharesolvedbyFEtechnique.Inthecomputation,noadditionalassumptionandthenonlineariterationarerequired,andacriterionforself-adaptivecomputationisproposedtomaintainsufficientcomputingaccuracyforthechangesizesoftimesteps.Inthenumericalcomparison,thevariationsofmaterialpropertieswithtemperature,moisturecontent,andbothtemperatureandmoisturecontentaretakenintoaccount,respectively.Satisfactoryresultshavebeenobtained,indicatingthattheproposedapproachiscapableofdealingwithcomplexnonlinearproblems.

  • 标签: 有限元分析 非线性传输 自适应系统 热量转移 离散特性
  • 简介:Basedontheextendedhomogeneouscapacityhighprecisionintegrationmethodandthespectrummethodofvirtualboundarywithacomplexradiusvector,anovelsemi-analyticalmethod,whichhassatisfactorycomputationeffectivenessandprecision,ispresentedforsolvingtheacousticradiationfromasubmergedinfinitenon-circularcylindricalshellstiffenedbylongitudinalribsbymeansoftheFourierintegraltransformationandstationaryphasemethod.Inthiswork,besidesthenormalinteractingforce,whichiscommonlyadoptedbysomeresearchers,theotherinteractingforcesandmomentsbetweenthelongitudinalribsandthenon-circularcylindricalshellareconsideredatthesametime.Theeffectsofthenumberandthesizeofthecross-sectionoflongitudinalribsonthecharacteristicsofacousticradiationareinvestigated.NumericalresultsshowthatthemethodproposedismoreefficientthantheexistingmixedFE-BEmethod.

  • 标签: 同源体积高精度积分法 光谱法 矩阵转换法 柱形壳强化
  • 简介:Fastsolvinglarge-scalelinearequationsinthefiniteelementanalysisisaclassicalsubjectincomputationalmechanics.Itisakeytechniqueincomputeraidedengineering(CAE)andcomputeraidedmanufacturing(CAM).Thispaperpresentsahigh-efciencyimprovedsymmetricsuccessiveover-relaxation(ISSOR)preconditionedconjugategradient(PCG)method,whichmaintainstheconvergenceandinherentparallelismconsistentwiththeoriginalform.Ideally,thecomputationcanbereducednearlyby50%ascomparedwiththeoriginalalgorithm.Itissuitableforhigh-performancecomputingwithitsinherentbasichigh-efciencyoperations.Bycomparingwiththenumericalresults,itisshownthattheproposedmethodhasthebestperformance.

  • 标签: 预处理共轭梯度法 大型线性方程组 有限元分析 松弛 对称 计算机辅助制造
  • 简介:Heattransportatthemicroscaleisofvitalimportanceinmicrotechnologyapplications.Theheattransportequationisdifferentfromthetraditionalheattransportequationsinceasecondorderderivativeoftemperaturewithrespecttotimeandathird-ordermixedderivativeoftemperaturewithrespecttospaceandtimeareintroduced.Inthisstudy,wedevelopahybridfiniteelement-finitedifference(FE-FD)schemewithtwolevelsintimeforthethreedimensionalheattransportequationinacylindricalthinfilmwithsubmicroscalethickness.Itisshownthattheschemeisunconditionallystable.Theschemeisthenemployedtoobtainthetemperatureriseinasub-microscalecylindricalgoldfilm.Themethodcanbeappliedtoobtainthetemperatureriseinanythinfilmswithsub-microscalethickness,wherethegeometryintheplanardirectionisarbitrary.

  • 标签: 混合有限元-有限差分格式 热传导方程 圆柱薄膜 半微尺度厚度 非条件稳定 温度