外文翻译---改造在寒冷气候下单户家庭房屋的太阳能热水器的生活热水的分析VIP免费

附录附录A外文资料RetrofittingDomesticHotWaterHeatersforSolarWaterHeatingSystemsinSingle-FamilyHousesinaColdClimate:ATheoreticalAnalysisAbstract:Oneofthebiggestobstaclestoeconomicprofitabilityofsolarwaterheatingsystemsistheinvestmentcost.Retrofittingexistingdomestichotwaterheaterswhenanewsolarhotwatersystemisinstalledcanreduceboththeinstallationandmaterialcosts.Inthisstudy,retrofittingexistingwaterheatersforsolarwaterheatingsystemsinSwedishsingle-familyhouseswastheoreticallyinvestigatedusingtheTRNSYSsoftware.Simulationmodelsusingforcedcirculationflowwithdifferentsystemconfigurationsandcontrolstrategiesweresimulatedandanalysedinthestudy.Acomparisonwithastandardsolarthermalsystemwasalsopresentedbasedontheannualsolarfraction.Thesimulationresultsindicatethattheretrofittingconfigurationachievingthehighestannualperformanceconsistsofasystemwheretheexistingtankisusedasstorageforthesolarheatandasmallertankwithaheaterisaddedinseriestomakesurethattherequiredoutlettemperaturecanbemet.Anexternalheatexchangerisusedbetweenthecollectorcircuitandtheexistingtank.Forthisretrofittedsystemanannualsolarfractionof50.5%wasachieved.Aconventionalsolarthermalsystemusingastandardsolartankachievesacomparableperformanceforthesametotalstoragevolume,collectorareaandreferenceconditions.Keywords:solarthermalstoragetankwaterheaterretrofitdomes1.IntroductionOneofthebiggestobstaclestotheeconomicprofitabilityofdomesticsolarwaterheating(SWH)systemsistheinvestmentcost.Theinstallationcostofforcedcirculationsystemsusedincoldclimatescanrepresentupto50%ofthetotalinvestmentcostdependingonthesizeandtypeofsystem.Also,thesolarstorageisoneofthemostexpensivecomponentsinasolarwaterheatingsystem.RetrofittingexistingdomesticwaterheaterswhennewSWHsystemsareinstalledcanreducethetotalinvestmentcostbydecreasingboththeinstallationandmaterialcosts.InSwedentherearemorethanhalfamillionelectricallyheatedsinglefamilyhousesthatuseconventionalwaterheatersfordomestichotwaterproduction.SuchretrofittingneedstobecarriedoutwithconsiderationofthecoldSwedishclimate.Insuchregionsthesolarstorageisplacedindoorsandafreezeprotectionmediumrunsinsidethecollectorcircuit.Sinceexistingwaterheatersarenotprovidedwithaheatexchanger,anexternaloneshouldbeused.Therearetwomaintypesofsystemsdesignedwithanexternalheatexchangeroutsidethestorage:thermosyphonandforcedflowcirculation.CruickshankandHarrison,in2004and2006,investigatedthistypeofthermosyphonsystemsintheCanadiancoldclimate.In2011,thesameauthorsstudiedtheperformanceofseriesandparallelconnectedthermosyphonstorages.ThermosyphonsystemsbecamepopularinseveralpartsoftheworldsuchasEasternAsiaandAustralia,mainlyduetotheirsimplicityandreliability.Thethermosyphondrivingforcedependsonthepressuredifferenceandfrictionallossesbetweentheheatexchangerside-armandthetank.Hence,thegeneratedflowwillbeacomplexfunctionofthestateofchargeofthetank,thetemperatureprofilealongtheheatexchangerandpipes,theheightdifferencebetweenthetopoftheheatexchangerandthetopofthetankandthepressuredropintheheatexchanger,pipingandconnections.Suchdependenceontheheatexchangerpressuredropandtankcharacteristicslimitshowtheretrofitiscarriedout,wheretheheatexchangershouldbeplacedandwhichstoragetankscanbeused.Moreover,whenproperlydesigned,forcedcirculationsystemscansignificantlyachievehigherperformancescomparedwithnaturalconvectiondrivensystems.Thisismai...