Abstract
Currently, more and more attention is being paid to the problem of effective application of ozone-safe refrigerating agents used in the cycles of vapor-compression refrigeration machines. This has become especially important when a number of ozone-safe refrigeration agents have a large global warming index, which has recently been unacceptable with respect to the environment worldwide. Therefore, conducting studies to evaluate the performance of new refrigerating agents as a result of replacing some refrigerating agents with others is an urgent task. At the same time it is necessary to try to keep the same equipment as it was before the replacement of the working agent. In this connection the justified efficiency of vaporcompression refrigeration machines at replacement of freons are an integral part of modernization of refrigeration systems. This paper presents a study of the efficiency of vapor-compression single-stage cycles of refrigeration machines when operating with different refrigerating agents. Thermodynamic evaluation of different ozone-safe refrigerating agents was carried out in comparison with forbidden ozone-safe refrigerating agent – dichlorodifluoromethane. In the course of the conducted research the cold-productivity and effective power of the refrigeration cycle for the considered refrigerating agents were determined. An estimation of the refrigerating agent value and the degree of cycle perfection for different refrigerating agents has been carried out. Specific volumetric refrigerating capacity of the investigated refrigerating agents for the considered cycle and parameters has been determined.As a result of this research, the most expedient refrigerating agent was recommended for replacement at the investigated parameters and cycle of the refrigeration machine.