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简介：Anaccuratecracksurfaceopeningdisplacementformulaforedgecracksinfinitebodieshasbeenderived,andwassubsequentlyusedtodevelopwide-rangeclosed-formweightfunctionsforedgecracks.Theanalyticalweightfunctionisgeneralandcanbeeasilyusedtodetermineaccuratestressintensityfactorsandcracksurfaceopeningdisplacementsforarbitrarilyloadededgecrackswithhighefficiency.Exampleshavebeengivenforproblemsofedgecrack(s)withanumberoftypicalloadconditionsforillustration.

简介：Astandardconservationformisderivedinthispaper.ThehyperbolicityofHelbing’sfluiddynamictrafficflowmodelisproved,whichisessentialtothegeneralanalyticalandnumericalstudyofthismodel.Onthebasisofthisconservationform,alocaldiscontinuousGalerkinschemeisdesignedtosolvetheresultingsystemefficiently.Theevolutionofanunstableequilibriumtrafficstateleadingtoastablestop-and-gotravelingwaveissimulated.Thissimulationalsoverifiesthatthemodelistrulyimprovedbytheintroductionofthemodifieddiffusioncoefficients,andthushelpstoprotectvehiclesfromcollisionsandavoidetheappearanceoftheextremelylargedensity.

简介：ThispaperpresentsaclosedformsolutionandnumericalanalysisforEshelby’sellipticinclusioninaninfiniteplate.Thecomplexvariablemethodandtheconformalmappingtechniqueareused.Thecontinuityconditionsforthetractionanddisplacementalongtheinterfaceinthephysicalplanearereducedtothesimilarconditionsalongtheunitcircleofthemappingplane.Thepropertiesofthecomplexpotentialsdefinedinthefiniteellipticregionareanalyzed.Fromthecontinuityconditions,onecanseparateandobtaintherelevantcomplexpotentialsdefinedintheinclusionandthematrix.Fromtheobtainedcomplexpotentials,thedependenceoftherealstrainsandstressesintheinclusionfromtheassumedeigenstrainsisevaluated.Inaddition,thestressdistributionontheinterfacealongthematrixsideisevaluated.Theresultsareobtainedinthepaperforthefirsttime.

简介：为了解决乘波体偏离设计条件下气动特性会恶化，特别在低速时，升力严重不足这个问题，提出了通过增大后掠角生成前缘涡，增加背风面的升力，以改善乘波体低速气动性能.首先使用VisualBasic编程语言，并通过CATIA软件二次开发技术，实现了锥导乘波体的参数化设计和自动生成.再通过控制圆锥角和流场长度这两个设计参数，获得了大后掠乘波体构型.最后，运用剪切应力输运（shear-stress-transport，SST)模型，计算了所得乘波体的气动特性，并分析了流场变化，发现乘波体在设计状态下激波能很好附着在前缘上，在小的正攻角下，乘波体可获得比设计状态更高的升阻比，满足巡航要求.运用I.模型计算了乘波体的低速气动特性，得到了不同攻角下升力、阻力和升阻比的变化规律.研究结果发现，乘波体在低速下产生了明显的涡结构，在合适攻角下，能产生数量可观的附加升力，提高了乘波体的水平起降性能.