Lead Performer: Oak Ridge National Laboratory – Oak Ridge, TN
June 22, 2023
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Lead Performer: Oak Ridge National Laboratory – Oak Ridge, TN
Partner: Honeywell
DOE Total Funding: $1,500,000
Project Term: May 1, 2022 – April 30, 2024
Funding Type: Lab Award
Project Objective
Pool boiling is the primary mode of heat transfer that occurs in flooded evaporators used for HVAC&R applications. The extensive knowledge of new refrigerants in pool boiling is critical for designing next-generation heat exchangers with enhanced performance and reduced refrigerant charge. However, the published literatures on pool boiling with ultra-low-GWP refrigerants (<150 GWP) are far from sufficient, and most of them were focused on the plain surface only. Oak Ridge National Laboratory will evaluate the pool boiling heat transfer of new refrigerants (<150 GWP) on both plain and enhanced surfaces. The team will design and build a closed loop setup to study the pool boiling heat transfer for low and medium pressure refrigerants. The potential candidates of low-GWP refrigerant may include R1233zd(E), R1336mzz(E), R1234yf, R1234ze, and R471A. The team will also develop new enhanced surfaces to improve heat transfer performance. In the second half of the project, the team will pursue a CRADA partnership with equipment manufacturers (Carrier, Emerson) or refrigerant manufacturers (Chemours, Honeywell, Koura) to further develop enhanced heat transfer technology for the selected low GWP refrigerant.
Project Impact
This project is poised to contribute significantly to the nation's ambitious climate mitigation goals, aiming to reduce greenhouse gas emissions by 50-52% by 2030 compared to 2005 levels. It will deliver actionable results for the HVAC industry, facilitating the shift from high-GWP refrigerants to low-GWP alternatives (<150), resulting in a reduction of at least 96% in direct GHG emissions while ensuring the competitiveness of the U.S. HVAC market. Additionally, this project aligns with BTO's goal to decrease onsite energy intensity in buildings by 30% by 2035 and 45% by 2050, relative to 2005 levels, achieved through a minimum 10% improvement in energy efficiency and a saving of 250 TBtu in air conditioning and refrigeration systems.
Contacts
DOE Technology Manager: Payam Delgoshaei
Lead Performer: Cheng-Min Yang