introduction
L'énergieducourantocéaniqueestproportionnelleaucarrédelavitesseetdudébit.Comparéeauxvagues,l'énergieducourantocéaniquechangeplusdouceetplusrégulière.
Ce que l'on appelle le courant océanique fait principalement référence à l'écoulement relativement stable dans les voies d'eau sous-marines et les détroits ainsi qu'à l'écoulement d'eau de mer régulier causé par la marée.
Facteurs causant
Thisseawatercirculationisusuallycausedbytwofactors: Tout d'abord, theseasurfaceisblowingwithconstantwindalltheyearround, suchastheconstantsoutheastonthesouthsideoftheequator.Thewind, anditsnorthsideistheconstantnortheasterlywind.Thewindblowstheseawatertomakethesurfaceofthewatermove, andthemovementofthewatertransmitsthismovementtothedepthsofthesea.Asthedepthincreases, theseawaterflowratedecreases, sometimesthedirectionofflowwillgraduallychangewiththeincreaseofdepth, andeventheflowdirectionofthelowerseawaterisoppositetothatofthesurfaceseawater.InthenorthernandsouthernhalvesofthePacificandAtlantic, andthesouthernhalfoftheIndianOcean, thedominantwindsystemcreatesavast, counterclockwiseoceancirculation.Inlow-andmid-latitudewaters, windisthemaindrivingforceforoceancurrents.Secondly, thetemperatureandsalinityofseawaterindifferentseaareasareoftendifferent, andtheywillaffectthedensityoftheseawater.Thehighertheseawatertemperatureandthelowerthesaltcontent, thelessdensetheseawater. Ladifférencededensitéentrelesdeux les zones maritimes adjacentes peuvent également provoquer une circulation d'eau de mer. Le débit d'eau de mer génère une énergie considérable. On estime que le courant océanique mondial peut atteindre 5 TW.
Causesdes courants marins
Ces courants sont pleins d'eau, pourquoi se forment-ils des courants océaniques ? Il y a à peu près trois raisons à la formation de courants océaniques. La raison la plus importante est le vent.
Thesecondtypeofoceancurrentistheflowofseawatercausedbythedifferenceinseawatertemperatureandsalinityindifferentseaareas.Suchoceancurrentsarecalleddensitycurrents.Forexample, intheStraitofGibraltar, thesalinityoftheMediterraneanishigherthanthatoftheAtlantic, soatadepthof500m, theseafromtheMediterraneanflowstotheAtlanticthroughtheStraitofGibraltar, whileatthesurfaceoftheocean, theseafromtheAtlanticrushestotheMediterranean, supplementingthelackofMediterraneanseawater.
Les autres causes de courants océaniques comprennent les écoulements géostrophiques, les écoulements de compensation, les eaux de reflux, les écoulements de rift, les écoulements en aval, etc.
Méthode d'utilisation
La production d'énergie
Theutilizationmethodofoceancurrentenergyismainlypowergeneration.Itsprincipleissimilartowindpowergeneration.AlmostanyWindpowergenerationdevicescanbetransformedintooceancurrentpowergenerationdevices.However, sincethedensityofseawaterisabout1,000timesthatofairandmustbeplacedunderwater, oceancurrentpowergenerationhasaseriesofkeytechnicalproblems, includinginstallationandmaintenance, powertransmission, anti-corrosion, loadandsafetyperformanceinthemarineenvironment, etc.Inaddition, thefixedformandturbinedesignofoceancurrentpowergenerationdevicesandwindpowergenerationdevicesarealsoverydifferent.Theoceancurrentdevicecanbeinstalledandfixedontheseabedoronthebottomofthefloatingbody, andthefloatingbodyisfixedontheseabyananchorchain.Turbinedesigninoceancurrentsisalsoakeytechnology.
Aide à la navigation
L'usage traditionnel des courants océaniques par les êtres humains consiste à " pousser le bateau le long du fleuve ".
Usingoceancurrentstoaidnavigationisjustaspeopleoftensay "pushtheboatalongthewater." Inthe18thcentury, AmericanpoliticianandscientistFranklindrewamapoftheGulfStream.ThemapspecificallymarkstheflowdirectionoftheNorthAtlanticoceancurrentindetail, andisusedbysailingshipstoandfromNorthAmericaandWesternEurope, greatlyshorteningthetimetocrosstheNorthAtlantic.IntheEast, accordingtolegend, duringWorldWarII, theJapaneseusedtheKuroshioCurrenttosendfoodtothemainlandonraftsfromChinaandNorthKorea.Modernsatelliteremotesensingtechnologycanmeasureoceancurrentdatainvariousseaareasatanytime, andprovidethebestroutenavigationservicesforshipsontheocean.
Theoceancurrentpowergenerationisalsovaluedbymanycountries.In1973, theUnitedStatestestedagiantoceancurrentpowergenerationdevicecalled "Coriolis" .Thedeviceisapipelinetypehydroelectricgenerator.Theunitis110meterslong, withapipeopeningof170metersindiameter, andisinstalled30metersbelowtheseasurface.Undertheconditionofanoceancurrentflowrateof2.3meterspersecond, thedeviceobtains83,000kilowattsofpower.JapanandCanadaarealsovigorouslyresearchingandtestingoceancurrentpowergenerationtechnology.Inmycountry'soceancurrentpowergenerationresearch, prototypeshavealsoenteredtheintermediateteststage.
La technologie de production d'électricité par courant océanique, à l'exception des roues hydrauliques mentionnées ci-dessus, similaires à celles d'une autre centrale de déviation de canalisation.
Appareils de production d'électricité
Oceancurrentpowergenerationdevicesmainlyincludevanetype, parachutetypeandmagneticcurrenttype.Thevane-typeoceancurrentpowergenerationdeviceusesoceancurrenttopushtheblades, andthebladesdrivethegeneratortogeneratecurrent.Thevanescanbeeitherpropellertypeorrunnertype.Theparachute-typeoceancurrentpowergenerationdeviceiscomposedofdozensof "parachutes" connectedinseriesonanendlesshingedrope.The "parachute" inthedirectionoftheseacurrentisopenedbytheforceoftheseacurrent, andtheparachuteinthedirectionoftheseacurrentisclosedbytheforceoftheseacurrent.The opensandclosesinsequenceandreciprocates "parachute", drivingthehingeropeandthendrivingthehingeplateontheshiptorotate, andthehingeplatedrivesthepowergeneration.Machinepowergeneration.Themagneticcurrentoceancurrentpowergenerationdeviceusesseawaterastheworkingmedium, allowingseawaterwithalargenumberofionstopassthroughastrongmagneticfieldverticallytoobtaincurrent.Thedevelopmenthistoryofoceancurrentpowergenerationisnotlong, andthepowergenerationdeviceisstillinthesta recherche de principe géographique et essais à petite échelle.
Observation et analyse
Thetheoreticalestimateofoceancurrentenergyintheworldisabout10 ^ 8kW.Usingvariousobservationsandanalysisdataof130waterwaysandnavigationgatesalongthecoastofChina, thetheoreticalvalueoftheannualaveragepowerofChina'scoastaloceancurrentenergyisabout1.4 x 10 ^ 7kWbycalculationandstatistics.Amongthem, theoceancurrentsalongthecoastofLiaoning, Shandong, Zhejiang, Fujian, andTaiwanarerelativelyrichinenergy.Manywaterwayshaveanenergydensityof15-30kW / m2, whichhasgooddevelopmentvalue.ItisworthpointingoutthatChina'soceancurrentenergyisoneoftheregionswiththehighestpowerdensityintheworld, especiallytheJintang, GuishanandXihoumenwaterwaysinZhoushanIslands, Zhejiang.Theaveragepowerdensityisabove20kW / m2, et l'environnement de développement est Les conditions sont très bonnes.
Présentation connexe
Situation actuelle en Chine
China'sseaareaisvast, withwindcurrentsanddensitycurrents, coastalcurrentsanddeep-seacurrents.Thevelocityoftheseoceancurrentsismostly0.5nauticalmileperhour, theflowratedoesnotchangemuch, andtheflowdirectionisrelativelystable.Ifcalculatedatanaverageflowof100cubicmeterspersecond, theenergyofChina'soffshoreandcoastalcurrentscanreachmorethan100millionkilowatts.Amongthem, theTaiwanStraitandtheSouthChinaSeahavethemostabundantenergy.Theywillprovidesufficientandcheapenergyforthedevelopmentofindustriesinmycountry'scoastalareas.Electricity.
Il n'est ni menacé par les inondations ni affecté par les saisons sèches. Il s'écoule presque à un volume d'eau constant et à un certain débit tout au long de l'année.
Oceancurrentpowergenerationreliesontheimpactoftheoceancurrenttomaketheturbinerotate, andthentransformittoahighspeedtodrivethegeneratortogenerateelectricity.Oceancurrentpowerstationsaremostlyfloatingonthesea.Forexample, akindofoceancurrentpowerstationcalledthe'garland'iscomposedofaseriesofpropellers, bothendsofwhicharefixedonapontoonwithageneratorinstalledinit.Theentirepowerstationfloatsontheseainthedirectionofthecurrent, likeawreathdedicatedtoguests.Thereasonwhythiskindofpowerstationiscomposedofaseriesofpropellersismainlybecausetheflowvelocityoftheoceancurrentissmallandtheenergyperunitvolumeissmall.Itspowergenerationcapacityisusuallyrelativelysmall, andgenerallycanonlyprovideelectricityforlighthousesandlightboats, atmostitcanonlychargethebatteriesonthesubmarine.
Innovation technologique
TheUnitedStatesoncedesignedabarge-typeoceancurrentpowerstationwhosepowergenerationcapacityismuchgreaterthanthatofarosette-typepowerstation.Thiskindofpowerstationisactuallyaship, soitseemsmoreappropriatetocallitapowership.Hugewaterwheelsareinstalledonbothsidesoftheship'sgunwale, whichcontinuouslyrotateunderthepushofoceancurrentstodrivegeneratorstogenerateelectricity.Thegeneratedelectricityissentashoreviasubmarinecables.Thiskindofbarge-typepowerstationhasapowergenerationcapacityofabout50,000kilowatts, andbecausethepowerstationisbuiltonaship, itcansailtoanearbyporttoescapewhenthereisastrongwindandwavestoensurethesafetyofthepowergenerationequipment.
Inthelate1970s, foreigncountriesdevelopedanumbrella-typeoceancurrentpowerstationwithanoveldesign, whichwasalsobuiltonaship.Itisastringof50parachutesonalongropetogathertheenergyoftheoceancurrent.Thetwoendsoftheropeareconnectedtoformaring.Then, puttheropeonthetwowheelsanchoredinthesternofthecurrent.Theparachuteplacedintheoceancurrentispropelledbythestrongoceancurrent, andtheparachuteinthecountercurrentislikeastrongwindthatexpandsandexpandstheumbrella, movingalongthedirectionoftheoceancurrent.Theparachute'sropethendrivesthetwowheelsontheship, andthegeneratorconnectedtothewheelsalsorotatestogenerateelectricity, andtheelectricityitemitsistransmittedtotheshorethroughthecable.