制冷机组的工作原理与选型冷水机组系统 毕业论文外文翻译.doc

外文文献 TheworkingprincipleofrefrigerationunitsandSelection（ChilledWaterSystems） Received:JamesB.Bradfordetal.“HVACEquipmentandSystems”.HandbookofHeating,Ventilation,andAir-Conditioning.Ed.JanF.Kreider.BocaRaton,CRCPressLLC.2001. Abstract:Inthespaceoftheair-conditioning,refrigerationunitisnecessaryequipment.Refrigerationunitisthecoolingsystemofsomeoftheequipmentorallequipmentsupportinggroupassembledtogether,asawhole.Thiscompactunit,theuseofflexible,easymanagement,installationsimple,someofwhichunitsimplyconnecttotheuseofwaterandpowerforrefrigerationandair-conditioningengineeringdesignandconstruction,hesaid.Thispaperdescribesthecoldwater-coolingunits,itisthecompressor,condenser,evaporator,cutexpenditure,controlcomponentsandauxiliaryequipment,suchasassemblyasawhole,andspecificallyfortheair-conditionedterminalorotherworksofthecoldtemperature（Hot）water,accordingtotheenvironment,andspacerequirements,andmaketheappropriatechoiceofthechiller. Keywords:chiller,steamcompressionrefrigerator,reciprocatingcompressors,screw-typecompressors. Chilledwatersystemswereusedinlessthan4%ofcommercialbuildingsintheU.S.in1995.However,becausechillersareusuallyinstalledinlargerbuildings,chillerscooledover28%oftheU.S.commercialbuildingfloorspacethatsameyear（DOE,1998）.Fivetypesofchillersarecommonlyappliedtocommercialbuildings:reciprocating,screw,scroll,centrifugal,andabsorption.Thefirstfourutilizethevaporcompressioncycletoproducechilledwater.Theydifferprimarilyinthetypeofcompressorused.Absorptionchillersutilizethermalenergy（typicallysteamorcombustionsource）inanabsorptioncyclewitheitheranammonia-waterorwater-lithiumbromidesolutiontoproducechilledwater. OverallSystem Anestimated86%ofchillersareappliedinmultiplechillerarrangementslikethatshowninthefigure（BitondoandTozzi,1999）.Inchilledwatersystems,returnwaterfromthebuildingiscirculatedthrougheachchillerevaporatorwhereitiscooledtoanacceptabletemperature（typically4to7°C）（39to45°F）.Thechilledwateristhendistributedtowater-to-airheatexchangersspreadthroug