CASCADE REFRIGERATION SYSTEM WITH INVERSE BRAYTON CYCLE ON THE COLD SIDE

摘要

The cold store refrigeration system proposed herein features a cascade configuration which has a vapourrncompression cycle as the top cycle and an inverse Brayton as the bottom cycle. The cold store air is used asrnworking fluid in the Brayton cycle. Therefore, the cold side heat exchanger (that would be the evaporator inrna vapour compression cycle) is replaced by a cold air inlet. Frost formation inside the cold store, as well asrnthe heat load due to the air circulation fan, are hence eliminated. On the other hand, the Brayton cycle hasrnlower efficiency when compared to vapour compression cycles. This gap may be reduced once therntemperature range is lowered by the cascade configuration. The top vapour compression cycle may alsornrefrigerate the loading dock. This paper describes a first screening of the relevant design parameters for anrnoverall system optimization.