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SORACLASSESIVSEZABTEACHERSANNARITASBARDELLAEMILIANAMANCINIVINCENZORECCHIAPOWERPOINTPRESENTATIONREALIZEDBYLORENZOCORSETTICLASSVACRISTIANODIAMANTICLASSVAFRANCESCODORAZIOCLASSVALICEOSCIENTIFICOSTATALE“LEONARDODAVINCI“SORAITALYCOMENIUS13“ENCOHANENERGYINTHECONSUMERSHANDS”20052008TEACHERSANNARITASBARDELLAEMILIANAMANCINIVINCENZORECCHIACLASSESIVSEZABLICEOSCIENTIFICOSTATALE“LEONARDODAVINCI“SORAITALYCOMENIUS13“ENCOHANENERGYINTHECONSUMERSHANDS“20052008“ENCOHAN”PROJECTMEETINGINHUNGHERY6THNOVEMBER/11THNOVEMBER2006TEACHERSEMILIANAMANCINIVINCENZORECCHIA“ENCOHAN”PROJECTMEETINGINPOLAND25THMARCH/1STAPRIL2007TEACHERSANNARITASBARDELLACOORDINATORVINCENZORECCHIASTUDENTSFRANCESCAFORNARICLASSIVAMARTINALIBURDICLASSIVALUCALOMBARDICLASSIVALUIGIRECCHIACLASSIVACHIARAIAFRATECLASSIVBALESSIAPANTANOCLASSIVBILARIAURBANICLASSIVBSILVIAVENDITTICLASSIVBDRINKINGBIRDDRINKINGBIRDSARETHERMODINAMICALLYPOWEREDTOYHEATENGINESTHATMIMICKTHEMOTIONSOFABIRDDRINKINGFROMAFOUNTAINOROTHERWATERSOURCETHEYAREALSOKNOWNASHAPPY,DIPPY,DIPPING,TIPPY,TIPPING,SIPPY,SIPPING,DIPDIPORDUNKINGBIRDSCONSTRUCTIONANDMATERIALSADRINKINGBIRDCONSISTSOFTWOGLASSBULBS,JOINEDBYATUBETHEBIRDSNECKTHETUBEEXTENDSNEARLYALLTHEWAYINTOTHEBOTTOMBULBBUTDOESNOTEXTENDINTOTHETOPTHESPACEINSIDEISTYPICALLYFILLEDWITHCOLOUREDDICHLOROMETHANEALSOKNOWNASMETHYLENECHLORIDEAIRISREMOVEDFROMTHEAPPARATUS,SOTHESPACEINSIDETHEBODYISFILLEDBYDICHLOROMETHANEVAPOURTHEUPPERBULBHASA“BEAK“ATTACHED,WHICHALONGWITHTHEHEAD,ISCOVEREDINAFELTLIKEMATERIALTHEBIRDISTYPICALLYDECORATEDWITHPAPEREYES,ABLUETOPHATPLASTICANDASINGLEGREENTAILFEATHERTHEWHOLESETUPISPIVOTEDONAVARIABLEPOINTONTHENECKTHEDRINKINGBIRDILLUSTRATESTHECONVERSIONOFTHERMALENERGYINTOMECHANICALENERGYTHEHEADOFTHEBIRDISCOATEDWITHAFUZZYMATERIAL,ANDISINITIALLYSOAKEDINWATERSOTHATITWILLBEGINTOCOOLBYEVAPORATIONTHISPROVIDESTHETEMPERATUREDIFFERENCEFROMHEADTOTAILNECESSARYTORUNTHEHEATENGINEASTHEHEADCOOLS,THECOLOREDFLUIDISOBSERVEDTORISEUPFROMTHEBOTTOMOFTHEBIRDTHROUGHTHENECK,GRADUALLYSHIFTINGTHECENTEROFGRAVITYOFTHEBIRDTOWARDITSHEADTHEBIRDBENDSATTHEHIPSANDDIPSITSBILLINTOAGLASSOFWATERTHUSKEEPINGTHEHEADWETANDCOOLERTHANTHETAILASTHEFLUIDCONTINUESTORISEINTOTHEHEAD,THEFLUIDLEVELINTHEBOTTOMOFTHEBIRDEVENTUALLYDROPSBELOWTHEENDOFTHECONNECTINGTUBETHISALLOWSVAPORTOBEPULLEDUPTHROUGHTHENECKTOEQUILIBRATETHEPRESSURETHEFLUIDRUNSBACKDOWNINTOTHEBOTTOMOFTHEBIRD,THEBIRDSTANDSUPAGAIN,ANDTHECYCLEREPEATSINDEFINITELYTHEDRINKINGBIRDISBASICALLYAHEATENGINETHATEXPLOITSATEMPERATUREDIFFERENTIALTOCONVERTHEATENERGYTOKINETICENERGYANDPERFORMMECHANICALWORKLIKEALLHEATENGINES,THEDRINKINGBIRDWORKSTHROUGHATHERMODYNAMICCYCLETHEINITIALSTATEOFTHESYSTEMISABIRDWITHAWETHEADORIENTEDVERTICALLYWITHANINITIALOSCILLATIONONITSPIVOTDRINKINGBIRDDRINKINGBIRDTHECYCLEOPERATESASFOLLOWSTHEWATEREVAPORATESFROMTHEHEADEVAPORATIONLOWERSTHETEMPERATUREOFTHEGLASSHEADTHETEMPERATUREDROPCAUSESSOMEOFTHEDICHLOROMETHANEVAPORINTHEHEADTOCONDENSETHELOWERTEMPERATUREANDCONDENSATIONTOGETHERCAUSETHEPRESSURETODROPINTHEHEADIDEALGASLAWTHEPRESSUREDIFFERENTIALBETWEENTHEHEADANDBASECAUSESTHELIQUIDTOBEPUSHEDUPFROMTHEBASEASLIQUIDFLOWSINTOTHEHEAD,THEBIRDBECOMESTOPHEAVYANDTIPSOVERDURINGITSOSCILLATIONSWHENTHEBIRDTIPSOVER,THEBOTTOMENDOFTHENECKTUBERISESABOVETHESURFACEOFTHELIQUIDABUBBLEOFVAPORRISESUPTHETUBETHROUGHTHISGAP,DISPLACINGLIQUIDASITGOESLIQUIDFLOWSBACKTOTHEBOTTOMBULB,ANDVAPORPRESSUREEQUALIZESBETWEENTHETOPANDBOTTOMBULBSTHEWEIGHTOFTHELIQUIDINTHEBOTTOMBULBRESTORESTHEBIRDTOITSVERTICALPOSITIONIFAGLASSOFWATERISPLACEDSOTHATTHEBEAKDIPSINTOITONITSDESCENT,THEBIRDWILLCONTINUETOABSORBWATERANDTHECYCLEWILLCONTINUEASLONGASTHEREISENOUGHWATERINTHEGLASSTOKEEPTHEHEADWETHOWEVER,THEBIRDWILLCONTINUETODIPEVENWITHOUTASOURCEOFWATER,ASLONGASTHEHEADISWET,ORASLONGASATEMPERATUREDIFFERENTIALISMAINTAINEDBETWEENTHEHEADANDBODYTHISDIFFERENTIALCANBEGENERATEDWITHOUTEVAPORATIVECOOLINGINTHEHEADFORINSTANCE,AHEATSOURCEDIRECTEDATTHEBOTTOMBULBWILLCREATEAPRESSUREDIFFERENTIALBETWEENTOPANDBOTTOMTHATWILLDRIVETHEENGINETHEULTIMATESOURCEOFENERGYISHEATINTHESURROUNDINGENVIRONMENTTHETOYISNOTAPERPETUALMOTIONMACHINEDRINKINGBIRD1HEATENGINEAHEATENGINEISAPHYSICALORTHEORETICALDEVICETHATCONVERTSTHERMALENERGYTOMECHANICALOUTPUTTHEMECHANICALOUTPUTISCALLEDWORK,ANDTHETHERMALENERGYINPUTISCALLEDHEATHEATENGINESTYPICALLYRUNONASPECIFICTHERMODYNAMICCYCLEHEATENGINESAREOFTENNAMEDAFTERTHETHERMODYNAMICCYCLETHEYAREMODELEDBYTHEYOFTENPICKUPALTERNATENAMES,SUCHASGASOLINE/PETROL,TURBINE,ORSTEAMENGINESHEATENGINESCANGENERATEHEATINSIDETHEENGINEITSELFORITCANABSORBHEATFROMANEXTERNALSOURCEHEATENGINESCANBEOPENTOTHEATMOSPHERICAIRORSEALEDANDCLOSEDOFFTOTHEOUTSIDEOPENORCLOSEDCYCLEINENGINEERINGANDTHERMODYNAMICS,AHEATENGINEPERFORMSTHECONVERSIONOFHEATENERGYTOMECHANICALWORKBYEXPLOITINGTHETEMPERATUREGRADIENTBETWEENAHOT“SOURCE“ANDACOLD“SINK“HEATISTRANSFERREDFROMTHESOURCE,THROUGHTHE“WORKINGBODY“OFTHEENGINE,TOTHESINK,ANDINTHISPROCESSSOMEOFTHEHEATISCONVERTEDINTOWORKBYEXPLOITINGTHEPROPERTIESOFAWORKINGSUBSTANCEUSUALLYAGASORLIQUIDTHEPHISICSAROUNDTHEPHISICSAROUNDFIGURE1HEATENGINEDIAGRAMHEATENGINESAREOFTENCONFUSEDWITHTHECYCLESTHEYATTEMPTTOMIMICTYPICALLYWHENDESCRIBINGTHEPHYSICALD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