EXPERIMENTAL INVESTIGATION OF NH3/CO2 CASCADE SYSTEM AND COMPARISON TO R404A SYSTEM FOR SUPERMARKET REFRIGERATION
This study investigates the performance of an NH3/CO2 cascade system for supermarket refrigeration application in a laboratory environment. The tested CO2 system is designed and scaled to fulfil the requirements of an average size supermarket in Sweden. Possibility for hot gas defrost in the freezers has been investigated and compared to the conventional electric heaters defrost method. Two cascade condenser arrangements have been evaluated. The cascade system has been compared to R404A system installed in the same laboratory.The results show that connecting the cascade condenser via thermosyphon or hot gas de-superheat arrangements yields good system stability and heat transfer performance. Hot gas defrost successfully defrosted the freezer evaporator but with long period and higher energy consumption compared to the conventional electric defrost method. The tested cascade system had up to 60％ higher total COP compared to the R404A system installed in laboratory.
S.SAWALHA C.PERALES CABREJAS M.LIKITTHAMMANIT J.ROGSTAM P-O.NILSSON
Energy Technology Department, Royal Institute of Technology (KTH) Brinellv?gen 68, 10044 Stockholm S Universidad Politécnica de Valencia Camino de Vera, s/n, 46022 Valencia, Spain Sveriges Energi- och Kylcentrum AB Kungsgatan 2A, 641 30 Katrineholm, Sweden
国际会议
The 22nd International Congress of Refrigeration(第22届国际制冷大会)
北京
英文
2007-08-21（万方平台首次上网日期，不代表论文的发表时间）