Numerical simulation of bubbles deformation, flow and coalescence in a microchannel under pseudo-nucleation conditions

Abstract

The paper reports results of numerical study on bubbles deformation, flow and coalescence under pseudo nucleate boiling conditions in horizontal mini-/micro- channels. The numerical simulation, which is based on the multiphase model of volume of fluid (VOF) method, aims to study the corresponding flow behaviours of nucleate bubbles generated from the tube walls in mini/micro channels so as to understand the effect of confined surfaces/walls on nucleate bubbles and heat transfer. Under the pseudo or quasi nucleate boiling condition, small superheated vapour bubbles are injected at the wall to ensure that the bubbles generation is under a similar condition of real nucleation. The numerical study examined the fluid mechanics of bubble motion with heat transfer, but the mass transfer across the bubble-liquid interface is not simulated in the present work.