Professor Guoliang Ding of Shanghai Jiao Tong University (SJTU) Presents New Research on Smaller Diameter Copper Tubes at the Tenth IIR Gustav Lorentzen Conference on Natural Refrigerants

Research Focuses on Minimizing Refrigerant Volume for Safe Room Air Conditioners with R290

New York, NY (June 26, 2012) — The ICA today announced new research on the application of smaller diameter copper in the design of room air conditioners that use propane as a refrigerant. The research results are reported in a research paper coauthored by scientists from Shanghai Jiao Tong University (SJTU); the International Copper Association Shanghai Office; and the Guangdong Kelon Air Conditioner Co.,Ltd., Shunde, Guangdong. The research was presented today at the Tenth IIR Gustav Lorentzen Conference on Natural Refrigerants at the Delft University of Technology in the Netherlands. 

As a renowned scientist at the Institute of Refrigeration and Cryogenics at SJTU, Professor Guoliang Ding personally presented the paper titled “Developing Low Charge R290 Room Air Conditioner by Using Smaller Diameter Copper Tubes.”   Coauthors are Wei Wu and Tao Ren from SJTU; Yongxin Zheng, Yifeng Gao and Ji Song from the ICA; and Zhongmin Liu and Shaokai Chen from Kelon. 

The research describes a new case study on an R290 room air conditioner with 5 mm tubes. R290 is considered an eco-friendly natural refrigerant R290 because it has zero ozone depletion potential (ODP) and virtually zero global-warming potential (GWP). Moreover, it does not give out any toxic decomposing agents on combustion and is compatible with the materials and lubricants used in air conditioning.

In the case study, the refrigerant charge for systems using 5-mm tubes was decreased in comparison to systems using 7-mm or 9.52-mm diameter tubes; and the cooling capacity was enhanced by optimization of heat exchanger as well as the matching of the entire system. Experimental results confirm the simulation results. 

“This research show that smaller diameter copper tubes are well-suited for developing safe room air conditioners with R290,” says Nigel Cotton, MicroGroove Team Leader for the International Copper Association. “And yet these research results have implications not only for R290 in residential air conditioners but also for a wide range of heat exchanger coils used in refrigerators, heat pumps and commercial air conditioning systems.”

Visit for information about smaller diameter copper tubes and where to obtain them.

About Professor Ding

DING Guoliang (G. L. Ding) was graduated from the Institute of Refrigeration and Cryogenics at Shanghai Jiao Tong University (SJTU) in 1993 and subsequently promoted to professor in 1998. He is the chairman of the Department of Power and Energy Engineering, SJTU; the president of Shanghai Society of Refrigeration; and the editorial board member of three international journals and three domestic journals. At various times, he worked as a post-doctoral researcher and a visiting professor at the University Karlsruhe, in Germany; and as a visiting professor at the University of Tokyo, in Japan.

Professor Ding has published 11 books, about 100 domestic journal papers, and about 80 international journal papers. These publications collectively have received more than 2000 citations. He owns 30 Chinese patents and 4 international patents. His major contributions are simulation and optimization techniques for refrigeration and air conditioning systems. The simulation and optimization techniques developed in his research group have been implemented with significant impact at many of the top refrigeration and air conditioning companies in the world.

About Gustav Lorentzen Conference

The conference is named in honor of Norwegian Scientist and engineer Gustav Lorentzen who rediscovered how CO2 could be used as a refrigerant in a simple and efficient way in heating and cooling applications. Traditionally, the IIR Gustav Lorentzen conferences attract a wide range of international specialists from science and industry sectors and facilitate an effective exchange of experience and knowledge. The Tenth IIR Gustav Lorentzen Conference on Natural Refrigerants will take place June 25-27 at the Delft University of Technology in the Netherlands. Visit for more information.

About ICA

The International Copper Association, Ltd. (ICA) is the leading organization for promoting the use of copper worldwide. ICA’s mission is to promote the use of copper by communicating the unique attributes that make this sustainable element an essential contributor to the formation of life, to advances in science and technology, and to a higher standard of living worldwide. Visit for more information about ICA.