Experimental investigation of the effect of solid-gas two-phase flow in CO₂ cascade refrigeration system

ABSTRACT

The dry ice sublimation process of CO₂ is a unique technique in which temperature ranges below the triple point of −56 °C can be achieved in a CO₂ refrigeration system. However, during the evaporation process of the actual refrigeration system, the dry-ice blockage maybe happens in the evaporator, which causes a risk of system failure in the suction of the compressor. In order to overcome this problem, in this study, an ultra-low temperature CO₂ cascade refrigeration system with a novel tapered evaporator/sublimator was designed and constructed. The novel evaporator/sublimator included a swirl promoter, which induces the swirling flow of solid-gas two-phase flow. Experiments were conducted for the investigation of solid-gas two-phase flow heat transfer characteristics in the evaporator/sublimator. According to the experimental results, it is verified that the CO₂ refrigeration system can operate consistently and steadily without dry ice blockage in the evaporator/sublimator. In addition, the dry ice particles are uniformly distributed along the inner wall of the evaporator/sublimator by the installation of the swirl promoter, and the heat transfer coefficient is considerably improved.

KEYWORDS:

• Dry ice
• CO₂
• cascade refrigeration
• two-phase flow
• ultra-low temperature

Acknowledgments

The authors gratefully acknowledge the financial support from the Research Council of Norway and user partners of HighEFF (Centre for Environment-friendly Energy Research, 257632/E20).

Additional information

Funding

This publication has been funded by HighEFF - Centre for an Energy Efficient and Competitive Industry for the Future.

Notes on contributors

Haruhiko Yamasaki

Haruhiko Yamasaki received the B.Eng., M.Eng., and Dr. Eng. degrees from the Department of Mechanical Engineering, Doshisha University, Kyoto, Japan, in 2011, 2013, and 2016, respectively. He is currently an assistant professor in the Department of Mechanical Engineering, Osaka Prefecture University, Sakai, Japan. His current interests are energy system using natural refrigeration and energy environmental protection engineering using nonthermal plasma. Dr. Yamasaki is a member of the IEEE Industry Application Society, the Japan Society of Mechanical Engineers, and the Institute of electrostatics, Japan.

Hiroshi Yamaguchi

Hiroshi Yamaguchi is a professor of the Department of Mechanical Engineering at Doshisha University in Japan and a member of the Energy Conversion Research Center of Doshisha University. He graduated from Doshisha University in 1977 and received the degree of Dr. Eng from the University of Manchester Institute of Science and Technology (UMIST) in 1982. His areas of expertise include experimental and computational fluid mechanics and fluid engineering, involving basic study and applications for supercritical CO2 flow, solar energy conversion, ultra-low-temperature refrigeration, non-Newtonian and viscoelastic fluids, magnetic fluids, and functional fluids, and more than 150 articles, including books, have been published in these fields.

Önder Kizilkan

Onder Kizilkan is a professor of the Mechanical Engineering Department at Isparta University of Applied Sciences in Turkey. He received his Ph.D. in Mechanical Engineering from Suleyman Demirel University, Turkey, in 2008. He has also worked as a visiting at UOIT in Canada between 2011-2012 and at Doshisha University in Japan, between 2019-2020. Dr. Kizilkan’s research interests are energy and exergy analyses of thermal systems, solar energy, energy storage systems, CO2 power cycles, and refrigeration. He is the author or co-author of several publications, which have been published in journals and conference proceedings. He has served as a Guest Editor of well-known international journals and edited many books. He has also given his efforts for many symposiums as an organizing committee member or chair.

Takeshi Kamimura

Takeshi Kamimura received the B.Eng., degree from Kanto Gakuin University, Kanagawa, Japan in 1986. From 1986 he works in the Mayekawa MFG. in Japan. After researching thermal systems such as ice storage and heat pumps, he is currently the Head of Research and Development Center in Mayekawa MFG.

Kazuhiro Hattori

Kazuhiro Hattori received the B.Eng., M.Eng., and Ph.D. degrees from Kyoto Institute of Technology, Kyoto, Japan in 1995, 2000, and 2008, respectively. From 2000 he works in the Research Laboratories, Mayekawa MFG. in Japan. Currently, he is the Division Manager of Research and Development Division in Mayekawa MFG. Dr. Hattori is a member of the Japan Society of Mechanical Engineers, Japan Society of Refrigerating and Air Conditioning Engineers, and the Institute of Electronics, Information and Communication Engineers, Japan.

Petter Nekså

Petter Nekså received the M.Eng. and Ph.D. degrees from Norwegian Institute of Technology, Trondheim, Norway, in 1986 and 1992, respectively. He is currently a chief research scientist at SINTEF Energy Research and Adjunct Professor at Norwegian University of Science and Technology, Trondheim, Norway. His current interests are refrigeration and heat pump technology in general and CO2 technology for various applications. He has authored more than 140 peer-reviewed papers in scientific journals and more than 100 technical reports within the area of refrigeration and process engineering.