Subcooled Boiling of PF-5060 Dielectric Liquid on Microporous Surfaces

Presented are the results of experiments that investigated nucleate boiling of PF-5060 on microporous Cu surface layers at saturation and 10 K, 20 K, and 30 K subcooling. The three microporous layers, electrochemically deposited on $10×10mm2$ Cu substrates and investigated herein, are $∼139μm$⁠, $171μm$⁠, and $220μm$ thick. The critical heat flux increases linearly with increased subcooling, $ΔTsub$⁠, at an average rate of 4.5%/K. For the $171μm$ thick, Cu microporous surface, saturation boiling CHF of $27.8W/cm2$ increases to $63.25W/cm2$ at $ΔTsub=30K$⁠, while the saturation $hMNB$ of $13.5W/cm2K$ decreases slightly to $12.7W/cm2K$ at $ΔTsub=30K$⁠. The values of the surface superheat, $ΔTsat$⁠, at $hMNB$ and CHF increase from 2.0 K and 2.16 K at saturation to 4.2 and 6.42 K at 30 K subcooling.