CH-85-05-1 -- Internal Performance of a Refrigerant Mixture in a Two-Evaporator Refrigerator PDF

When a refrigerant mixture is used as the working substance in a refrigerating system, the temperature rises during a constant-pressure boiling process and falls during a constant-pressure condensation. If the refrigeration application requires cooling a fluid through a temperature range, the match of this range with the evaporating temperatures will potentially result in an improved coefficient of performance. The cooling of air in the two-compartment domestic refrigerator can approximate the desirable cooling application.

This paper presents some experimental measurements on a two-evaporator system with a 50% mixture of R12/R114 and compares that system to the performance of a system using R12 alone. The varying temperatures of the mixture are observed, although pressure drop in the evaporators reduces the actual change in the COP in comparison to the maximum possible.