About this presentation

related to ATMOsphere America 2012
published on 12 June 2012
24 pages
2 MB

Hrnjak sets the scene by discussing natural refrigerants CO₂, ammonia and hydrocarbons in different applications and their “serious potential to become mainstream option” in vapour compression. He provides examples of current advances with ammonia refrigerant such as hermetic compressors, microchannel condensers and Ni brazed plate evaporators. His presentation gives a short history of natural refrigerants and dispels some misconceptions. Hrnjak highlights that when the reality of HXs, compressor and expansion devices come into a play, this is when the thermophysical properties become way more important than thermodynamic properties, and this is where CO₂ and typically all natural refrigerants are good. He concludes that when treated with understanding each of the main alternatives are excellent and competitive and he briefly discusses areas of further improvement and some of the remaining challenges such as initial higher cost.

About the speaker(s)

Pega Hrnjak

 

Professor Hrnjak is Co-Director of the Air Conditioning and Refrigeration Center (ACRC) at the University of Illinois at Urbana Champaign, an NSF founded university–industry cooperative research center. Pega is also a founder and President of R&D company CTS, which bridges ACRC activities (precompetitive research in function of education) and industry. He is an active member or fellow of ASME, ASHRAE, IIR, SAE and IIAR, and an editor or member of the boards of several professional scientific journals. He is a recipient of Gustav Lorentzen, J&E Hall and Rittinger medals among other awards.