Effects of Surface Engineering on HFE-7100 Pool Boiling Heat Transfer

This study explores pool boiling of HFE-7100 on copper surfaces. The key objective of this study was to examine the effects that surface engineering has on nucleate boiling performance. The surface enhancements studied are roughness, artificial nucleation sites, and the combination of both. Data were gathered at Case Western Reserve University’s Two-Phase Flow and Thermal Management Laboratory. Observingroughness between 0.480 μm to 7.564 μm shows that HTC improves with increasing roughness. Observing hole diameters from 1 mm to 3 mm and hole pitch, or spacing to diameter ratio, from 1.75 to 3.5; a configuration with hole diameter of 1 mm and pitch of 2.5 provides the best improvement to HTC compared to a bare surface with roughness of 0.480 μm, while the configuration with hole diameter of 1 mm and pitch of 3.5 provides worse HTC compared to a bare surface with roughness of 0.480 μm. Applying a roughness to a hole pattern also improves HTC with increasing roughness compared to both a bare surface with roughness of 0.480 μm, as well as to the hole pattern alone. The majority of the surface enhancement modes yields overall improvements in HTC. The introduction of surface enhancement generally decreases CHF.