Energy losses in the immersion compression refrigerator

Abstract

The results of theoretical and experimental investigations on energy losses which arise in small refrigerating compressors used in agriculture and food industry have been presented in this monograph. The refrigerating compressor has been treated as a system composed of subsystems which represent the main parts of the set. All internal processes in each subsystem have been defined and then relationships between the subsystems and the external environment have been found. The model developed has enabled the main factors behind as well as sources and localization of internal and external losses to be specified. The experimental investigations have been done on an especially designed experimental setup, allowing measurement of pressure and temperature in selected characteristic points. The experimental results have been obtained for various sets of initial temperatures of the refrigerated liquid and external environment. Varied mass of the refrigerated liquid and two different sets of cooling temperature have been investigated. The analysis has shown that the most significant energy losses have occurred when refrigerating compressor starts. The relationship between the amount of refrigerated liquid and energy used in a cooling process has been determined. It has been found that energy used to refrigerate unit mass in one cooling cycle depends essentially on the amount of refrigerated mass. This means that it is possible to select an adiabatic tank of an optimal size to be adequate for a chosen refrigerating compressor. Such solution can minimize the energy supplied to the refrigerating system with respect to the amount of refrigerated mass.