Humboldt Fellow Conducts Research on Environmentally-Friendly Refrigerants for High-Temperature Heat Pumps

Dr. Riley Barta, of Purdue University in the USA, will spend the next two years as a guest researcher supported by a Humboldt Research Fellowship at the Bitzer-Chair of Refrigeration, Cryogenics and Compressor Technology. During his time at the chair he will conduct research under Prof. Dr. Ullrich Hesse on the topic of high-temperature heat pumps.

The waste heat given off by many industrial processes is often not at a high enough temperature to be efficiently converted to electricity. One possibility to increase the usability of this waste heat is to apply a high-temperature heat pump to efficiently increase the temperature of the waste heat. Riley Barta will focus on the identification of refrigeration mixtures that can be applied in this high-temperature application, with the goal of increasing the acceptance of environmentally-friendly refrigerants in high-temperature heat pump applications and supporting the decarbonisation of industry.

During his Mechanical Engineering Studies, Barta spent a semester abroad at the KIT in Karlsruhe and at the beginning of his Ph.D., he took part in the International Refrigeration and Compressor Course (IRCC) between the TU Dresden and Purdue University. These experiences, combined with the fact that his Ph.D. advisor, Prof. Eckhard Groll, is a German native, grew his fascination with both the German culture and education system. When he first came to Dresden in 2016 as a part of the IRCC, he met Dr. Christiane Thomas and Prof. Ullrich Hesse from the Bitzer-Chair of Refrigeration, Cryogenics and Compressor Technology at the TU Dresden for the first time. „We got along well from the beginning, and both the laboratories at the chair as well as the working environment within the team impressed me very much. Throughout the course of my Ph.D., I was then able to stay in touch with Dr. Thomas and Prof. Hesse. This led to the chance for me to voice my desire to return to Germany to continue research after my Ph.D. ended, which they both supported,“ noted Barta.

Riley Barta studied Mechanical Engineering at Purdue University in the USA, where he graduated with his Bachelor of Science in 2016 and his Ph.D. in 2020 at the Ray W. Herrick Laboratories. During his Ph.D., the mechanical engineer worked on the application of natural refrigerants in refrigeration systems in order to aid in the development of environmentally-friendly refrigeration technology. He investigated the connections between component design and thermal systems behavior using both numerical and experimentally techniques, specifically focusing on the advantages and disadvantages of Carbon Dioxide (R-744) as a refrigerant. The 27-year old grew up in Denver, Colorado in the USA.

Contact for Journalists:

Dr. Riley Barta
Bitzer-Chair of Refrigeration, Cryogenics and Compressor Technology
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