Optimization of Lubricant Return in Refrigeration Systems

Oil is necessary for most of the heat pumps, cooling and freezing equipment, for proper operation of the compressor and other moving parts. Speed of the refrigerant vapor in the critical section, which is suction piping, is strongly dependent on the evaporating temperature, but also on the actual device performance. Well-designed piping is essential to the proper function of the cooling devices or heat pumps and affects the efficiency of the device. The aim of this paper is to describe problems of returning of oil in refrigerant devices and investigate the exact solution of design of refrigerant speed for carrying the lubricating oil in all segments of refrigerant pipes. Paper is based on facts obtained during developing of new refrigeration equipment. The resulting proposal of the device was numerically verified.