DESIGN AND RATING OF A 2-STAGE VAPOR-COMPRESSION REFRIGERATION SYSTEM

The non-isentropic compression processes in the compressor of a vapor- compression system consume more power with increasing thermal lift bec ause of the increasing slope of the constant isentropic line on a log( p)-h diagram. However, in a two-stage system (TSS), compression is per formed in stages, thereby allowing the compressors to operate efficien tly close to the saturation curve. In this paper, thermodynamic models of the TSS are developed to simulate system performance with respect to the interstage temperature and heat-exchanger parameters. The TSS p erformance is better than for a simple cycle and depends on the inters tage temperature of the flash intercooler. Models are used to derive t he optimum total heat exchanger area between the evaporator and conden ser. (C) 1998 Elsevier Science Ltd. All rights reserved.