简介：本文介绍了一种近岸往复流同向推动涡轮发电设备，由进水通道、排水通道和横向通道组成，近岸海水的往复流动通过发电设备被转化为涡轮的单向旋转.同时，根据近岸往复流特点，分析了近岸海水流速、横流通道两端压差和输出功率关系，当近岸海水流速较小时，需要增加进水通道流通截面积；当近岸海水流速较高时，需要减小涡轮发电机转矩，提高发电设备输出功率.

简介：涡轮增压器是船舶动力装置的重要部件,其工作状况是否良好,对改善气缸的燃烧条件,降低燃油消耗,提高柴油机的功率有着十分重要的意义.由于船舶柴油机涡轮增压器的工况恶劣,使用中易发生故障.文章通过对柴油机涡轮增压器运行中常见故障的分析,阐述了故障原因,提出了排除故障的方法及预防建议.

简介：文章首先分析了支持向量机智能诊断的理论,接着介绍了废气涡轮增压器的原理及常见故障,最后研究其在船舶柴油机增压器故障诊断中的应用,并用仿真实验验证了支持向量机在柴油机废气涡轮增压器故障诊断中具有的拟合能力。研究表明,在正确选取特征参数的基础上,采用SVM方法进行船舶柴油机废气涡轮增压器智能故障诊断是可行的。

简介：Fishareabletomakegooduseofvortices.Inacomplexflowfield,manyfishcontinuetomaintainbothefficientcruisingandmaneuverability.Traditionalman-madepropulsionsystemsperformpoorlyincomplexflowfields.Withfish-likepropulsionsystems,itisimportanttopaymoreattentiontocomplexflowfields.Inthispaper,theinfluenceofvorticesonthehydrodynamicperformanceof2-Dflapping-foilswasinvestigated.Theflapping-foilheavedandpitchedundertheinfluenceofinflowvorticesgeneratedbyanoscillatingD-sectioncylinder.Anumericalsimulationwasrunbasedthefinitevolumemethod,usingthecomputationalfluiddynamics(CFD)softwareFLUENTwithReynolds-averagedNavier-Stokes(RANS)equationsapplied.Inaddition,dynamicmeshtechnologyandpostprocessingsystemswerealsofullyused.Thecalculationsshowedfourmodesofinteraction.Thehydrodynamicperformanceofflapping-foilswasanalyzedandtheresultscomparedwithexperimentaldata.Thisvalidatedthenumericalsimulation,confirmingthatflapping-foilscanincreaseefficiencybyabsorbingenergyfrominflowvortices.

简介：文章简述了旋挖钻机的施工工艺,并结合泰州大桥施工实例分析了旋挖钻机的特点,希冀为旋挖钻机的广泛应用提供参考。

简介：Inordertostudycavitationcharacteristicsofa2-Dhydrofoil,themethodthatcombinesnonlinearcavitationmodelandmixed-iterationisusedtopredictandanalyzethecavitationperformanceofhydrofoils.ThecavitationelementsarenonlinearlydisposedbasedontheGreenformulaandperturbationpotentialpanelmethod.Atthesametime,themethodthatcombinescavityshapeforfixedcavitylength(CSCL)iterationandcavityshapeforfixedcavitationnumber(CSCN)iterationisusedtoworkoutthethicknessandlengthofhydrofoilcavitations.Throughanalysisofcalculationresults,itcanbeconcludedthatthejumpofpressureandvelocitypotentiallyexistbetweencavitationendareaandnon-cavitationsareaonsuctionsurfacewhencavitationoccursonhydrofoil.Incertainanglesofattack,thecavitationnumberhasanegativeimpactonthelengthofcavitations.Andunderthesameangleofattackandcavitationnumber,thebiggerthethicknessofthehydrofoil,theshorterthecavitationslength.