Full Description

A refrigerator/freezer (RF) system is simulated that has two complete and independent refrigeration cycles for the two compartments. It employs a nonazeotropic refrigerant mixture (NARM) in each of the cycles and uses countercurrent heat exchangers throughout. In a standard cabinet, this RF s simulated to provide energy savings of 30% compared to the current US RF designs. A 19% improvement can be expected from the dual-circuit system using R12 alone, and an additional 11% improvement can be gained by replacing R12 with the selected NARMs in countercurrent heat exchangers. Advantages of this system include greatly reduced energy consumption, easy temperature and humidity control for each compartment, no humidity or odours transferred between compartments, and increased time between defrost cycles. Disadvantages include additional hardware necessary, compressor size, and the difficulties of using a NARM.

KEYWORDS: calculating, non azeotropic, refrigerants, mixtures, R12, refrigerators, freezers, refrigeration, cyclic, heat exchangers, energy conservation, energy consumption, temperature, humidity, controls, odor

Citation: ASHRAE Transactions, vol.97, pt. 2, Indianapolis, IN 1991