For the first time in Korea, we have successfully conducted a cooling performance test of a large-capacity ultra-low temperature turbo-Brayton cooling system using a refrigerant that has no effect on global warming.

The research team of Director Koh Jun-seok of the Energy Storage Research Lab at the Korea Institute of Machinery and Materials (President Ryu Seok-hyeon) under the Ministry of Science and ICT announced on the 20th that they had developed a turbo-Brayton cooling system using a zero GWP refrigerant and successfully conducted an operation test confirming a cooling capacity of over 10 kW at -100°C.

This is the first domestic demonstration of large-capacity ultra-low temperature cooling technology using a turbo-Brayton cooling system.

The Korea Mechanical Engineering & Construction Co. developed a turbo-Brayton cooling system using its own centrifugal compressor and turbo-expander.

In industries centered around the semiconductor industry, there has been an increasing demand for large-scale ultra-low temperature chillers with a cooling temperature of -100℃ or lower and a cooling capacity of 10kW or more. This study confirmed that turbo-Brayton cooling technology is a promising technology that can satisfy these industrial demands.

Turbo-Brayton cooling technology is a cooling system that uses turbomachinery that rotates at high speeds of tens to hundreds of thousands of rpm, and has been used in limited areas such as superconducting cable cooling, cryogenic fluid supercooling, and LNG re-liquefaction.

On the other hand, recently, large-scale semiconductor manufacturing processes and bio-industry The demand for ultra-low temperature cooling technology is rapidly increasing, while at the same time, carbon neutrality and strengthening refrigerant regulations are demanding the development of highly efficient, low-GWP cooling technology.

Existing vapor-compression type ultra-low temperature chillers use high GWP refrigerants or natural refrigerants with a high risk of explosion, and have difficulties in increasing the capacity due to equipment constraints, and in controlling the operating temperature and capacity due to the characteristics of the refrigerant and limited control methods.

On the other hand, the turbo-Brayton cooling system developed this time can freely control the capacity in the range of 5.5 to 11 kW, and is a technology that can satisfy all of the recent industrial demands of 'ultra-low temperature, large capacity, and high efficiency' by using a Zero GWP refrigerant that goes beyond Low GWP.

The research team developed and localized the centrifugal compressor and turbo expander, which were core components that had previously been entirely dependent on imports, and succeeded in conducting an actual performance test of the turbo-Brayton cooling system, which had never been successfully tested in Korea, thereby securing full-cycle technology.

“Success in large-scale cooling of over 10kW at an ultra-low temperature of -100℃ using a zero GWP refrigerant is an achievement that meets the needs of the industrial sector,” said Ko Jun-seok, head of the Korea Institute of Machinery and Materials. “We will develop the system in a form suitable for industrial chillers within three years and advance it to a level where it can be used in various industrial fields, including the semiconductor industry.”

Meanwhile, this study was conducted with the support of the basic project of the Korea Institute of Machinery and Materials, ‘Development of Core Machines for Ultra-low Temperature Cooling Systems for Semiconductor Manufacturing Processes.’