简介:1INTRODUCTIONReservoirsedimentationisrecognizedasoneofthemainproblemsafectingtheeconomicsofmanywaterresourcesprojects.Manmad...
简介:Pointabsorberwaveenergydevicewithmultipledegreesoffreedom(DOF)isassumedtohaveabetterabsorptionabilityofmechanicalenergyfromoceanwaves.Inthispaper,acoaxialsymmetricarticulatedpointabsorberwaveenergyconverterwithtwodegreesoffreedomispresented.Themechanicalequationsoftheoscillationbuoywithpowertake-offmechanism(PTO)inregularwavesareestablished.Thethree-dimensionalnumericalwavetankisbuiltinconsiderationofthebuoymotionbasedupontheCFDmethod.Theappropriatesimulationelementsareselectedforthebuoyandwaveparameters.ThefeasibilityoftheCFDmethodisverifiedthroughthecontrastbetweenthenumericalsimulationresultsoftypicalwaveconditionsandtestresults.Insuchcase,thebuoywithsingleDOFofheave,pitchandtheircouplingmotionconsideringfree(noPTOdamping)anddampedoscillationsinregularwavesaresimulatedbyusingtheverifiedCFDmethodrespectively.Thehydrodynamicandwaveenergyconversioncharacteristicswithtypicalwaveconditionsareanalyzed.Thenumericalresultsshowthattheheaveandpitchcanaffecteachotherinthebuoycouplingmotion,hydrodynamicloads,waveenergyabsorptionandflowfield.ThetotalcapturewidthratiowithtwocoupledDOFmotionishigherthanthatwithasingleDOFmotion.ThewaveenergyconversionofacertainDOFmotionmaybehigherthanthatofthesinglecertainDOFmotioneventhoughthewaveisattheresonanceperiod.Whenthewaveperiodsarehighenough,theinteractionbetweenthecoupledDOFmotionscanbeneglected.