PFAS-Free Two-Phase Direct-to-Chip Cooling Technology

This technical report presents experimental results on a new PFAS-free refrigerant, R-4101A, for two-phase direct-to-chip (2P DTC) cooling systems. The report outlines the increasing demand for advanced cooling technologies in data centers driven by the rapid growth of AI workloads and the associated rise in computing power density. It details the thermal performance of R-4101A, which is a zeotropic mixture, and compares it to an existing refrigerant, R-515B. The findings indicate that R-4101A demonstrates comparable cold plate thermal performance while potentially reducing the approach temperature difference in coolant distribution units (CDUs). The report emphasizes the importance of selecting refrigerants that meet evolving environmental regulations, particularly concerning PFAS substances. The results suggest that R-4101A could enhance the efficiency and sustainability of thermal management solutions in next-generation AI data centers, aligning with regulatory requirements and industry trends towards safer refrigerants.