Experimental and Theoretical Evaluation of NH3/CO2 Cascade System for Supermarket Refrigeration in Laboratory Environment
2006 (English)Conference paper (Refereed)
In this paper we investigate and evaluate the performance of an NH3/CO2 cascade system forsupermarket refrigeration application in a laboratory controlled environment. The system solutionunder investigation replicates a medium size supermarket in Sweden. CO2 is used at the low andmedium temperature levels with several possibilities available for system variations and parametricanalysis. Along with the experimental rig a computer simulation model has been developed toevaluate the performance and test the influence of different parameters on the system’s efficiency.Overall system evaluation has been performed. Different circulation rates at the mediumtemperature level have been tested. Control system of the freezing cabinets has been evaluated.The results of the tests show that the experimental COP’s are in good agreement with the onescalculated by the computer model. Evaluation of different circulation rates show that it should bekept as low as possible and there is no optimum value as in the case of conventional brine. Thecontrol of the electronic expansion valve should be based on the evaporating pressure rather thanmeasuring surface temperature of the evaporator.
Place, publisher, year, edition, pages
Research subject SRA - Energy
IdentifiersURN: urn:nbn:se:kth:diva-62908OAI: oai:DiVA.org:kth-62908DiVA: diva2:481329
7th IIR Gustav Lorentzen Conference on Natural Working Fluids. 2006: Trondheim, Norway
QC 201202022012-02-022012-01-202012-02-02Bibliographically approved