简介:BasedonthetraditionalSmoothedParticleHydrodynamics(SPH)algorithm,thelinked-listsearchalgorithmcombinedwiththevariablesmoothinglengthandsquaresupportdomainwasputforwardtoimprovethecalculationefficiencyandguaranteethecalculationaccuracy.Thephysicalprocessofhighvelocityfragmentimpactonabroadsideliquidcabinwasprogrammedforsimulation.ThenumericalresultsagreedwellwiththoseofthegeneralsoftwareANSYSAUTODYN,whichverifiestheeffectivenessandfeasibilityofthenumericalmethod.Fromtheperspectiveoftheouterplatethicknessoftheliquidcabin,thewidthoftheliquidcabin,andincidentangleofthefragment,theinfluenceoftheseparametersonprotectivemechanismswasanalyzedtoprovideabasisforprotectivedesignofabroadsideliquidcabin.Resultsshowthattheinfluenceofouterplatethicknessisnotobvious;therefore,theconventionaldesigncanbeadoptedinthedesignoftheouterplate.Thewidthoftheliquidcabinhasagreatinfluenceontheresidualvelocityofthefragmentandthewidthoftheliquidcabinshouldbedesignedtobeaswideaspossibleunderthepremiseofmeetingotherrequirements.Thereisacertainincidentangleinwhichthevelocityattenuationofthefragmentismostobvious,andthehigh-pressurezoneneartheinnerplateisasymmetric.Theinnerplateofliquidcabinshouldbestrengthenedaccordingtothehullform,principaldimensions,andvulnerablepoints.
简介:Inordertostudytheeffectsofwetcompressiononatransoniccompressor,afull3-Dsteadynumericalsimulationwascarriedoutundervaryingconditions.Differentinjectedwaterflowratesanddropletdiameterswereconsidered.Theeffectofwetcompressionontheshock,separatedflow,pressureratio,andefficiencywasinvestigated.Additionally,theeffectofwetcompressiononthetipclearancewhenthecompressorrunsinthenear-stallandstallsituationswasemphasized.Analysisoftheresultsshowsthattherangeofstableoperationisextended,andthatthepressureratioandinletairflowratearealsoincreasedatthenear-stallpoint.Inaddition,itseemsthatthereisanoptimumsizeofthedropletdiameter.
简介:近来,韩国“岁月”号沉没的新闻引发了业界对于船舶设计、建造、运营安全性的广泛关注。在船舶大型化、智能化、技术化日趋发展的今天,不时出现的各类海事安全和环保突发事件在不断提醒人们,海事技术、规则、立法虽然看似庞杂,可对于“阴睛不定”的海事风险而言,依然需要因时而变、与时俱进。国际海事组织(IMO)是联合国负责海上航行安全和防止船舶造成海洋污染的一个专门机构,其通过国际海事立法、修订等形式,致力于船舶安全、环境保护和绿色能效等技术规范的不断提升。近年来,IMO通过的相关新公约、新规范和新标准越来越多,越来越严格,这对我国船舶工业提出了更高的要求与挑战。日前,IMO在海上安全委员会(MSC)第93次会议上又通过多项决议,其中涉及液货船、客船、极地船舶建造及运营的相关议案将对船舶行业产业较大的影响。