简介：Wecomputethewakeofatwo-dimensionalandthree-dimensionalflexiblefininanunsteadyflowfieldwithheavingandpitchingmotionsusingFLUENT.Deflexionmodeisusedforanon-uniformcantileverbeamwithnon-uniformlydistributedload.Theeffectofchordwisedeflexionlengthonthecharacteristicsofpropulsionisdiscussedfortwo-dimensionalflexiblefin.Thethrustcoefficientdecreases,propulsiveefficiencyincreasesandtheintensityofturbulenceattenuatesgraduallyasthedeflexionlengthincreases.Forathree-dimensionalflexiblefin,theintensityofthevortexintheplaneofsymmetryishigherthanthatintheplaneat3/4spanlengthofthecaudalfin.Butthepropulsiveperformanceachievedisnotwhatweexpectedwiththegivendeflexionmode.

简介：Unpredictableairmovementshaveprovedtobeaprobleminpreviousstudiesinvestigatingrobotcommunicationbymeansofairbornepheromonechemicals.Theprojectdescribedinthispaperinvestigatestheuseofairvortexringsasameansofcarryingpheromonechemicalsbetweentransmittingandreceivingrobots.Sensitivitytochemicalsincludingpheromonesreleasedbyconspecificsisessentialformanyaspectsofaninsect’slife.Theyassistinfindingfood,locatingamate,avoidingdangerandhelpcoordinatetheactivitiesofsocialinsects.Inthefuture,autonomousrobotswillbechallengedbymanysituationssimilartothosethatfaceinsectsandothersimplecreatures.Chemicalcommunicationmayproveusefulfortheserobotsaswell.Thispaperdescribestheequipmentdevelopedforgeneratinganddetectingvortexrings.Resultsofexperimentsinvolvinglocationandtrackingofasequenceofpheromonevortexringsarealsopresented.

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简介：Oneofmanyinterestingresearchactivitiesinbiofluidmechanicsisdedicatedtoinvestigationsoflocomotioninwater.Someofpropulsionmechanismsobservedintheunderwaterworldareusedinthedevelopmentprocessofunderwaterauto-nomicvehicles(AUV).Inordertocharacteriseseveralsolutionsaccordingtotheirmanoeuvrability,influenceonthesur-roundingfluidandenergeticefficiency,adetailedanalysisoffin-likemovementisindispensable.Inthecurrentpaperananalysisofundulatory,oscillatoryandcombinedfin-likemovementsbymeansofnumericalsimulationiscarriedout.TheconservationequationofmassandtheconservationequationofmomentumaresolvedwiththeFiniteVolumeMethod(FVM)byuseofthesoftwareCFX-10.0.Theundulatoryandoscillatoryfinmovementsaremodelledwithanequationthatisimplementedwithinanadditionalsubroutineandjoinedwiththemainsolver.Numericalsimulationsarecarriedoutinthecomputationaldomain,inwhichonefinisfixedinaflow-throughwaterduct.SimulationsarecarriedoutintherangeoftheRenumberupto105.Theresultsshowsignificantinfluenceofappliedfinmotiononthevelocitydistributioninthesurroundingfluid.