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1、SpecifyingSteamSurfaceCondenserscoolingwaterenteringthecondenserbyElliotSpencerandthequantityofwateravailable.GrahamMfg.Co.,Inc.,GreatNeck,LongIsland,N.Y.Thesteamcondensingtemperaturecangetdowntoaslowas5FaboveFactorsaffectingcondenserdesignandselection.theenteringcoolingwatertempe
2、rature,Atypicalairconditioningsurfacecondenserspecificationisincluded.butinmostairconditioninginstallationsthedifferentialis20F,sometimes10F,butseldomsmaller,asfromtheturbinemanufacturer.thecloserapproachwouldrequireacostlyamountofcondensersurface.THEFORMULAfordeterminingtheGenera
3、llyspeaking,onsystemswhereInpractice,coolingtowerwaterisfirstamountofsurfacerequiredinasurfacethemotivesteampressureisusedintherefrigerantcondenser,condenserisasfollows:approximately150lbandtheturbineiswhereitrisesabout10FandisthenQ=UA(LMTD)(1)dischargingtoavacuumof26.inchesavaila
4、bleforsteamcondensing.Thewhereofmercury(4in.Hgabsolute),asteamgreatbulkofsteam-drivencen-trifugalQ=Heattobeabsorbed,Btuh=rateof14-16lbperhrperbhpisrefrigerationsystemsoperatewithapoundsperhourofsteamtimes950economicallyfeasible.AlthoughsteamcondenservacuumofBtuperpound;greatereffi
5、ciencyisavailableatapproximately4in.Hgabs.,whichisU=Overallheattransferrate,Btuperincreasedcost,utilitycostsforthisequivalenttoacondensing(hr)(sqft)(F);typeofinstallationseldomjustifytemperatureof125.4F.Thus,referringA=Surfacerequired,sqft;reducingthesteamconsumptionbytoFig1andpre
6、sumingthat85FLMTD=Logemeantemperaturemeansofhigheref-ficiencyturbinesorcoolingwaterissuppliedtothesystemdifferencebetweencondensinglowercondensingpressures.Whenfromthecoolingtowers,watertemperatureandcoolingwater.specialconditionsarepresent,thetemperatureintothesteamcondenserNoatt
7、emptwillbemadetogothroughspecifyingengineermayconsiderisapproximately95F.Assumingaaformalcondenserselection.Theeitheroftheabovemodificationstoturbinesteamrateof14-16lbperhrperprocedureforcondenserratingisimproveperformance.bhp(bhppertonofrefrigerationisamplycoveredinthepublication
8、ofapproximately1)andacondensingHe
