暖通空调外文

42 ASHRAE Journal ashrae.org February 2010ASHRAE50JOURNAL1959–2009YEARSASHRAEASHRAE50JOURNAL1959–2009YEARSByA.I.MCfARLAN,fELLOwASHRAEREpRINtEdfROMASHRAEJOURNAL,dECEMBER1959ImprovedZoningBettersDepartmentStoreAirConditioningZoningAirConditioningthisairwenttofittingroomsaroundtheexterior,andinothercasestooffices,bothofwhichmustbeheatedwhileinteriorsalesareasmustsimul-taneouslybecooled.Therewerereheatcoilsinthebranchesfromthemainairstreamtothefittingroomsandoffices,whichmeantthatduringtheheatingseasonairwascooledtoatem-peraturewhichwouldsatisfytheinte-riorsalesspace,andthenpartoftheairbledofftoheatthechilledairthroughreheatcoilsinordertoheattheexteriorofficesandfittingrooms.Theheatedairhadtoberecooledbeforebeingreheatedasitwentthroughitscycle.Departmentstoresarezonedonthebasisofoverallfloors,orcombi-nationoffloors,frequentlywithoutregardtointeriorandexteriorspacesorsimultaneousheatingandcoolingrequirements.Drawingsforapro-poseddepartmentstoredisplayedanairconditioningunittobelocatedineachoffourcornersofthreefloors;onefloorlargelybelowground,agroundfloor,andthetopfloorunderaroof.Alargepartoftheairfromeachunitwasdeliveredtointeriorareas,butthedrawingsshowedairleavingthemaincoilatthesametemperatureforinte-riorandexteriorareas.Insomecases,officebuildingscanbetracedtotheperipheralsystem.Costsinvolvingdoublefans,elaboratedampers,andinmanycaseslong,high-pressureductsystemsarechargeabletocoolingtheinteriorareawhiletheexteriorisbeingheated.Butperipheralofficebuildingzoningcanbegreatlyimproved,withsav-ingsinbuildingandairconditioningequipment.A.I.McFArlAn,FellowASHrAeA.I.McfarlangraduatedfromLehighUniversityin1926withadegreeinmechanicalengineering.from1926to1940heworkedatyorkInternational.In1940,hebecamethevicepresidentofKerbySaundersofNewyorkCity,whereheremaineduntil1945.duringworldwarll,McfarlanworkedontheManhattanprojectfortheUnitedStatesgovernment.McfarlanwasthepresidentofA.I.McfarlanCompany,adesign-buildair-conditioningconstructioncompanyhefoundedin1945inNewyorkCity.HemovedthecompanytoSpringfield,N.J.,in1968andfinallysettledinwestfield,N.J.,in1976.HewaspresidentoftheNewyorkCityChapteroftheAmericanSocietyofRefrigeratingEngineersfrom1949–1950,andservedontechnicalcommittees6.2and9.4.Hereceivedmorethan50patentsinair-conditioningandheatrecoveryapplications.Mcfarlanretiredfromhiscompanyin1993.HediedinAugust1995attheageof92.DesigneroftheairconditioninginstallationfortheSibleyDepartmentStoreinRochester,N.Y.,theauthordiscusseshowtoimproveantiquatedandinefficientzoningbytheuseoftheClosedandStagedCyclewhichwasusedatSibley’sandincludesonesystemforheatingandcooling.Alsodiscussedarethestagingofcompressorsforreductionofhpinairconditioningsystems,theClosedCycleheatpumptotransferheatwithinaprojectandvolumaticcontrol.nimprovementwhichshouldreceivemoreconsiderationindepartmentstoreaircondi-Ationingiszoning.Partofthecompli-cationintheairconditioningoflargeFebruary 2010 ASHRAE Journal 43ASHRAEASHRAE50JOURNAL1959–2009YEARSAllofthisunnecessarilyaddedreheatisnullifiedwithmoreexcesscoldoutsideair,thenreheatedagainonthenextcycle.Thus,doublefansandbuildingspacetohouseunneces-saryequipmentproducedcostlyandinefficientresults,whereanefficientsystemwouldhavecostonlyalittlemore.Departmentstoreswithlargeinteriorareasrequirecoolingtheyeararound.Inmanycaseswithhighintensitylightingandheavypopulationareas,theinternalloadissubstantiallyhigherthanforthelesspopulatedsummercondition.Duringtheheatingseasondepartmentstoresdesireatemperaturebetween70°Fand75°F,whereunderpeakcondi-tionsinthesummer,whentheoutsidetemperatureis95°Forhigher,78°Fto80°Finsideisgenerallyaccept-able.Thismeansthatairmustbesuppliedtointernalareasduringtheheatingseasonatalowertempera-turethanwillberequiredduringthecoolingseason.Increasedpopula-tionsandincreasedlightingincreasetherequiredtemperaturedifferencebetweenthesupplyairandroomtem-peratureduringtheheatingseasoninsuchinstallations.Ifmostairconditioningengi-neerswerequestionedastotheleastexpensivemethodofcoolinginteriorareasinthewinterseason,theywouldrecommendoutsideairtotheextentnecessaryabovetheventilationratetosatisfytheinsidetemperature.Thisanswerhasresultedinanumberofproblemswhicharequestionablysolvedbyusingdoublefans,gener-allytripledampers,spillairshafts,andamultiplicityofdampercontrols.Thesedoublefansanddamperstakealotofspacewhichisalwaysvalu-Twootherstoresrecentlyoccupiedbrancheswiththreestorybuildings,eachhavingabasement,groundfloor,andsecondfloorunderaroof.Twolargedoublefansystemssupplyairtohalfofeachfloor,completelydisregardingdifferentzonerequire-mentsonthethreefloors.Duringtheheatingseason,airwithvaryingproportionsofoutsideair,inaddi-tiontotheventilationrequirements,isprovidedatatemperaturelowenough,whenitisavailable,tosatisfythebasementwhichrequirescoolairtheyeararound.Theairfromthesamefansandcoilsisfurnishedtothegroundfloorafterhavingbeencooledtosatisfythebasement,thenreheatedtosatisfythegroundfloor.Theairtothetopfloorislikewisefirstreducedintemperature,andthenmustbereheatedevenmore,sincethisfloorisunderacoldroof.fI