Performance comparison of oil and oil less system with changing evaporator shape in domestic refrigerator

International Conference on Compressors and their Systems 2019

Oh, Been^1 ; Sangkyung, Na^1 ; Kim, Hyun^3 ; Choi, Gyungmin^2

Graduate School of Mechanical Engineering, Pusan National University, Busan

46241, Korea, Republic of^1

Department of Mechanical Engineering, Pusan National University, Busan

46241, Korea, Republic of^2

LG Electronics, 391-2 Changwon, Gyeong Nam

51533, Korea, Republic of^3

关键词: Cooling Capacity;    Cyclic tests;    Domestic refrigerators;    Grooved tubes;    Heat transfer area;    Operating characteristics;    Performance comparison;    Steady-state energies;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/604/1/012039/pdf
DOI  :  10.1088/1757-899X/604/1/012039

来源: IOP

【 摘 要 】

Generally, lubricating oil has the role of reducing the friction of the compressor. However, due to the presence of lubricating oil, the heat transfer performance in the evaporator is decreased and the pressure drop of the pipe in the system is increased. In this paper, performance of the oil absence was experimentally evaluated in the domestic refrigerator with different types of evaporator. The experiments were conducted in oil and oil-less systems. The on-off cyclic test and steady state energy test were performed to analyze the system performance such as power consumption, cooling capacity, coefficient of performance and operating characteristics. The grooved tube evaporator and the plane tube evaporator were also compared to investigate the influence of the lubricating oil with the evaporator tube type. The power consumption of the oil-less system was decreased compare to the oil system. This is because the pressure drop in the capillary tube was decreased and the heat transfer performance from the compressor discharge to the condenser outlet is improved. On the evaporator side, the grooved tube evaporator was improved compared to the plain tube evaporator in all systems. The inner fin on the grooved evaporator caused a larger heat transfer area and heat transfer coefficient of the refrigerant side. The oil that exists between the inner fins of the grooved evaporator influenced decreasing the heat transfer area.