Nucleate Pool Boiling on A Plain Surface

Abstract

M ultiphase flows are used in a wide range of industrial applications such as heat exchangers, nuclear reactors, food production, chemical processes, and electronic cooling. It is important to understand, model and simulate multiphase phenomena such as boiling, for cooling technology.In boiling systems, a large amount of heat is transferred from the surface within small temperature differences between the surface and saturation temperature of the fluid. Although there are many experimental, computational and analytical studies on boiling phenomena, its highly complex physical mechanism hasn't been clarified yet. In recent years, bubbling characteristics have been observed visually on several surface materials with various surface properties such as roughness, cavity size, shape, and spacing. Zhang and Shoji (2003), made experiments on a silicon surface (15 mm diameter, 0.2 mm thickness) with distilled water [1]. They worked on cylindrical artificial cavities (10 µm diameter and 80 µm depth) arranged as single or twin cavities with 1, 2, 3, 4, 6 and 8 mm spacing. The bubbling behavior is recorded with a high-speed camera and temperature fluctuations beneath and around the cavities are measured with radiation thermometers. According to their observation and analysis, three significant factors involving nucleation site interactions are determined: hydrodynamic interaction between bubbles; thermal interaction between nucleation sites;