外文翻译太阳能空调系统综述有太阳能空调吗Word格式文档下载.docx
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外文翻译太阳能空调系统综述有太阳能空调吗@#@外文翻译--太阳能空调系统综述_有太阳能空调吗@#@@#@@#@翻译原文AReviewonSolarPoweredAirConditioningSystemRaviGugulothu,NagaSaradaSomanchi,HimaBinduBanothandKishanBanothuAbstractThetwentyfirstcenturyisrapidlybecomingtheperfectenergystorm,modernsocietyisfacedwithvolatileenergypricesandgrowingenvironmentalconcernsaswellasenergysupplyandsecurityissues.Oneofthegreatestchallengesfacingmankindinthetwentyfirstcenturyisenergy.Fossilfuelssuchascoal,petroleumandnaturalgashavebeenthemainenergyresourcesforeverythingvitalforhumansociety.Theburningoffossilfuelshascausedandiscausingdamagetotheenvironmentofearth.By2050thedemandforenergycoulddoubleoreventripleastheglobalpopulationgrowsanddevelopingcountriesexpandtheireconomies.Thishasalreadyraisedconcernsoverpotentialsupplydifficulties,depletionofenergyresourcesandexpeditingenvironmentalimpactslikeozonelayerdepletion,globalwarmingandclimatechangeetc.Themostabundantenergyresourceavailabletohumansocietyissolarenergy.Theutilizationofsolarenergyisasoldashumanhistory.Amongvarioustypesofrenewableenergyresources,solarenergyistheleastutilized.Airconditioningisessentialformaintainingthermalcomfortinindoorenvironments,particularlyforhotandhumidclimates.Today,airconditioningcomprisingcoolinganddehumidificationhasbecomeanecessityincommercialandresidentialbuildingsandindustrialprocesses.Duringthesummer,thedemandforelectricitygreatlyincreasesbecauseoftheextensiveuseofair-conditioningsystems.Thisisasourceofmajorproblemsinthecountry’selectricitysupplyandcontributestoanincreaseofCO2emissionscausingtheenvironmentalpollutionandglobalwarming.Ontheotherhand,vapourcompressionairconditioningsystemshaveimpactsonstratosphericozonedepletionbecauseofthechlorofluorocarbons(CFC)andthehydrofluorocarbon(HCFC)refrigerants.Theuseofsolarenergytodrivecoolingcyclesisattractivesincethecoolingloadisroughlyinphasewithsolarenergyavailability.Tocoolwithsolarthermalenergy,onesolutionistouseanabsorptionchillierusingwaterandlithiumbromidesolution.Solarairconditioningsystemshelptominimizefossilfuelenergyuse.Amongtheevolvingenergyefficientairconditioningtechnologiesareliquiddesiccantairconditioning(LDAC)systems,whichhaveshowedpromisingperformanceduringthepastdecadesandarebelievedtobeastrongcompetitorwiththewidelyusedconventionalairconditioningsystems(CAC).Desiccantevaporationcoolingtechnologyisenvironmentalfriendlyandcanbeusedtoconditiontheindoorenvironmentofbuildings.Unlikeconventionalairconditioningsystems,thedesiccantairconditioningsystemscanbedrivenbylowgradeheatsourcessuchassolarenergyandindustrialwasteheat.Inthisstudy,afocusismadeonreductioninAirConditioningcapacity,fuelsavingsandemissionreductionsattainablethroughtheuseofsolarenergy.Keywords:
@#@SolarEnergy,DesiccantAirConditioningSystem,Humidificationand.Dehumidification,ConventionalAirConditioning;@#@1.IntroductionAsakindofrenewableenergy,solarenergyispaidmoreandmoreattentionintheworld.Solarsystemcanbeclassifiedintotwocategories;@#@thosearethermalsystemswhichconvertsolarenergytothermalenergyandphotovoltaicsystemswhichconvertsolarenergytoelectricalenergy.However,moresolarradiationwhichfallingonphotovoltaiccellsisnotconvertedtoelectricity,buteitherreflectedorconvertedtothermalenergy.Thismethodleadstoadropofelectricityconversionefficiencyduetoanincreaseinthephotovoltaiccellsworkingtemperature.Inthepastcentury,scientificcommunityhasdevotedmuchefforttoprocureenergysustainabilityofhousingintwomaindirections;@#@thosearereducingexternalenergysupplyandusingrenewableenergyfortheremaining.Inbothways,solarresourcesaregainingpopularitybecausetheyincreaseenergyindependenceandsustainabilityatthesametimeofferingnearlyzeroimpacttotheenvironment.Themoderncomfortlivingconditionsareachievedatthecostofvastenergyresources.Globalwarmingandozonedepletionandtheescalatingcostsoffossilfuelsoverthelastfewyearstothedesignandcontrolofbuildingenergysystems.Solarenergyisabundantandclean,itismeaningfultosubstitutesolarenergyforconventionalenergy.Solarenergythereforehasanimportantroletoplayinthebuildingenergysystems.Theincreasingscarcityandcostoffossilfuelsandincentivestoreducegreenhousegasemissionshaveledtoagrowinginterestinsolarenergy.Solarenergyiswidelyaffordableandhasthecapabilitytomeethouseholddemandovertheyear.Unfortunately,itsintermittencyandvariabilitywithweatherconditions,timeandseasonsleadtoamismatchbetweenheatingdemandandsolarenergyavailability.Airconditioningsystemsareinstalledinbuildingstoprovidetheoccupantswithhealthyandproductiveenvironments.Considerableamountofenergyisconsumedintheoperationofthewidelyusedenergyinefficientconventionalairconditioningsystems,whichleadstoseveralenvironmentalproblemsthatarerelatedtoenergyproductionsuchasairpollution,globalwarmingandacidprecipitation.Fromrecentstudies,thosebuildingsareresponsiblefortheconsumptionofaround40%oftheprimaryenergyconsumptionandtheemissionofnearly33%ofthegreenhousegasesintheworld.Anairconditioningsystemconsistsofcomponentsandequipmentarrangedinsequentialordertoheatorcool,humidifyordehumidify,cleanandpurify,attenuateobjectionableequipmentnoise,transporttheconditionedoutdoorairandrecirculateairtotheconditionedspaceandcontrolandmaintainanindoororenclosedenvironmentatoptimumenergyuse.Mostoftheairconditioningsystemsperformthefollowingfunctions:
@#@a.Providethecoolingandheatingenergyrequiredb.Conditionthesupplyair,heatorcool,humidifyordehumidify,cleanandpurifyandattenuateanyobjectionablenoiseproducedbythesesystemsc.Distributetheconditionedair,containingsufficientoutdoorair,totheconditionedspace.d.Controlandmaintaintheindoorenvironmentalparameterssuchastemperature,humidity,cleanliness,airmovement,soundlevelandpressuredifferentialbetweentheconditionedspaceandsurroundingwithinpredeterminedlimits.1.1.Applicationsofairconditioningsystema.Institutionalbuildings,suchasschools,colleges,universities,libraries,hospitalsandnursinghomes,museums,indoorstadiums,cinematheatres..…etc.b.Commercialbuildings,suchasoffices,storesandshoppingcentres,supermarkets,departmentstores,restaurantsandothers.c.Residentialbuildings,includinghotels,motels,singlefamilyandmultifamilylowrisebuildingsofthreeorfewerstoriesabovegraded.Manufacturingbuildings,whichmanufactureandstoreproductsforexamplesmedicinese.ThetransportationsectorslikeAutomobiles,aircraft,railroadcars,busesandcruisingships....etcAirconditioningsystemsaremainlyfortheoccupant’shealthandcomfort.Theyareoftencalledcomfortairconditioningsystems.1.2.PrincipleofairconditioningsystemFigure1showsthewindowmountedairconditioningsystem.Thecabinetisdividedintoindoorandoutdoorcompartmentswhichareseparatedbyinsulatedwalltoreducetheheattransfer.TheDXcoilandindoorfanareintheindoorcompartment.Theoutdoorcompartmentcontainsthecompressors,condensers,outdoorfan,capillarytubeandfanmotor.Thefanmotoroftenhasadoubleendedshaftwhichdrivesbothfansatatime.Fig.1.WindowmountedairconditioningReturnairfromtheconditionedspaceflowsthroughacoarseairfilterandiscooledanddehumidifiedinaDXcoilandthenenterstheinletoftheindoorfan.Inaroomairconditioner,theindoorfanisaforwardcurvedcentrifugalfan.Theconditionedairispressurisedintheimpellerandforcedthroughtheairpassagethatleadstothesupplygrille.Theconditionedairisthensuppliedtotheconditionedspacetooffsetthespacecoolingload.Outdoorairisextractedbythepropellerfanandforcedthroughthecondensingcoils,inwhichhotgaseousrefrigerantiscondensedtoliquidrefrigerant.Duringcondensation,condensingheatisreleasedtotheoutsidethroughthecoolingair.Aportionofoutdoorventilationairisextractedbytheindoorfanandmixedwiththereturnair.Theopeningoftheoutdoorventilationairintakeisadjustable.Scientistsandengineersaretryingtodevelopmoreefficientairconditioningsystemsthatarecapableofachievinggoodindoorairqualitywithlowenergyconsumptionratesandairpollutionemissions.Amongtheevolvingenergyefficientairconditioningtechnologiesareliquiddesiccantairconditioning(LDAC)systems,whichhaveshowedpromisingperformanceduringthepastdecadesandarebelievedtobeastrongcompetitorwiththewidelyusedconventionalairconditioningsystems(CAC).Theairhandlinginairconditioningsystemswasmoistbecauseofthedehumidificationprocessinsummer,sobacteriawereeasilypropagatedanddeveloped.Inaddition,theairhumidityinmoistcentralairconditioningsystemsisseldomcontrolled.Thiscausespeopletofeeluncomfortableinsuchairconditioningrooms.Solarenergydrivenliquiddesiccantcoolingairconditioningsystems(LDCS)canimproveindoorairqualityandreduceelectricalenergyconsumptionandhavebeenregardedhighlybyresearchersandengineersinrecentyears.Thedesiccantbasedairconditioningsystemcomestobeoneoftheprospectivealternativesforthetraditionalvapourcompressionairconditioningsystems.1.3.Literat