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1、低溫與超導(dǎo)制冷技術(shù)Cryo.&Supercond.第42卷第9期RefrigerationVo1.42No.9跨臨界CO2蒸氣壓縮一引射制冷循環(huán)的性能分析張振迎,王洪利,李敏霞,馬一太(1.河北聯(lián)合大學(xué)建工學(xué)院,唐山063009;2.河北聯(lián)合大學(xué)冶金與能源學(xué)院,唐山063009;3.天津大學(xué)中低溫?zé)崮芨咝Ю媒逃恐攸c實驗室,天津300072)摘要:CO,跨臨界基本循環(huán)由于節(jié)流損失較大使其能效比較低,采用引射器替換節(jié)流閥可以回收部分膨脹功,進而提高循環(huán)的性能系數(shù)。針對跨臨界CO:壓縮一引射制冷循環(huán)建立
2、了熱力學(xué)模型,考慮了引射器噴嘴出17與蒸發(fā)器之間的壓力差異,并分析了吸入壓差值、氣體冷卻器壓力、氣體冷卻器出口溫度、蒸發(fā)溫度及蒸發(fā)器出口過熱度對循環(huán)性能的影響。結(jié)果表明:在一定工況下存在一最佳吸入壓差,使引射器提升壓力值和循環(huán)COP提高率達到最大值,典型空調(diào)工況下最佳吸入壓差約為0.34MPa。~/X)X差的取值對引射系數(shù)和循環(huán)最優(yōu)排氣壓力值影響很小。關(guān)鍵詞:制冷;引射器;CO2;跨臨界循環(huán);性能Performanceofejector—expansiontranscriticalCO2vaporco
3、mpressionrefrigerationcycleZhangZhenying,WangHongli,LiMinxia,MaYitai(1.CollegeofCivilEngineering,HebeiUnitedUniversity,Tangshan063009,China;2.CollegeofMetallurgyandEnergy,HebeiUnitedUniversity,Tangshan063009,China;3.KeyLaboratoryofMedium—LowTemperatureE
4、nergyEficientUtilizationofMinistryofEducation,TianjinUniversity,Tianjin300072,China)Abstract:ThebasictranscriticalCO2systemsexhibitslowenergyefficiencyowingtothelargethrottlinglosses.Replacingthethrottlevalvewithanejectorisaneffectivemeasureforrecoverin
5、gsomeofthelostenergyoftheexpansionprocess,thusim-provingthecycleperformance.AthermodynamicmodeloftheejectorexpansiontranscriticalCO2refrigerationcyclewasdevel-oped.Thepressuredropbetweentheevaporatorandtheoutletofthemotivenozzlewastakenintoaccountinthem
6、ode1.Efectsofparameters,suchasthesuctionpressuredrop,gascoolerpressure,gascooleroutlettemperature,evaporatortemperatureandevaporatoroutletsuperheatonthecycleperformancewereanalyzed.Theresultsshowedthatthereexitsanoptimumsuctionpres-suredropwhichgivesama
7、ximumrecoveredpressureorCOPimprovementrateunderaspecifiedcondition.Theoptimumsuctionpressuredropisabout0.34MPaunderthetypicalairconditioningworkingconditions.Thevalueofsuctionpressuredrophaslessinfluenceontheejectorentrainmentratioandtheoptimalgascooler
8、pressureofthecycle.Keywords:Refrigerationsystem,Ejector,CO2,Transcriticalcycle,Performancel引言單、成本低廉,用其替換節(jié)流閥,可以回收高壓工質(zhì)的壓力能,提高壓縮機入口壓力,從而改善制冷制冷劑替代和系統(tǒng)節(jié)能已成為制冷空調(diào)領(lǐng)域循環(huán)性能。的前沿課題。自然工質(zhì)CO以其環(huán)境友好性、安Li和Groll通過理論分析表明,在典型空調(diào)全性和良好的熱物理性質(zhì),被認為是最具潛力的工況下,