Nucleate Boiling on Ultra‐Smooth Surfaces: Study of Bubble Incipience at Submicronic Scale
Résumé
Pool boiling heat transfer characteristics and especially onset of nucleate boiling are investigated on rough to ultra-smooth metallic surfaces made of aluminum using two highly wetting fluids: acetone and ethanol. Different Au4G samples are polished to obtain RMS roughness at micro and nano-scale ranging from 14 μm to 30 nm. Pool boiling experiments are performed inside a transparent reactor at a controlled saturation temperature of the working fluid, enabling observations of the boiling process. The results presented in this communication are the preliminary results of an ongoing project which aims at studying the influence of controlled geometrical patterns at the submicronic scale on the boiling process and especially on the incipience of a bubble.