Plenary Lecture
Modeling for Refrigerant Characteristics in Non-Adiabatic Capillary Tube and Application to Vapor Compression Refrigeration Cycle Analysis
Professor Ji Hwan Jeong
School of Mechanical Engineering
Pusan National University
South Korea
E-mail: jihwan@pusan.ac.kr
Abstract: Most modern refrigerators incorporate heat transfer between the refrigerant in a capillary tube and the refrigerant in a suction line. This heat transfer is achieved by a non-adiabatic capillary tube called a capillary tube-suction line heat exchanger (CT-SLHX) and is supposed to improve the performance of the small vapor compression refrigeration cycle by removing some enthalpy of the refrigerant at the evaporator entrance. The thermodynamic properties of the refrigerant in the capillary tube and suction pipe are influenced by associated phenomena. A mechanistic model was developed for the analysis of the non-adiabatic capillary tube based on evaluation of various constituting correlations. This non-adiabatic capillary tube model is based on a homogeneous two-phase flow model. To investigate the effects of this CT-SLHX on the refrigeration cycle, a computer program was developed based on conservation equations of mass, momentum, and energy. The simulation results show that both the location and length of the heat exchange section influence the coefficient of performance (COP) as well as the cooling capacity. It is noteworthy that the influence was not monotonic; that is, the performance may be deteriorated under certain conditions.
Brief biography of the speaker: Prof. Ji Hwan Jeong graduated from the Seoul National University, Korea in 1988 and received his Ph.D. from the KAIST (Korean Advanced Institute of Science and Technology) in 1995. He did his post-doctoral research in the Technology Centre in Aerodynamics and Heat Transfer at Oxford University. After three years of research experience at KAERI (Korea Atomic Energy Research Institute), he joined the Faculty of the School of Mechanical Engineering at Pusan National University. He is author of about 80 papers published in international journals and conference proceedings, and invited book chapters. His research interests include multi-phase flow, heat transfer augmentation, heat exchangers, heat pump, and nuclear power plant safety analysis. He has also consulted in the nuclear and air conditioner industries.
He is currently a board member of the SAREK (The Society of Air-Conditioning and Refrigerating Engineers of Korea) and serves as editor of ‘International Journal of Air-conditioning and Refrigeration’ and ‘Journal of Mechanical Science and Technology’.