Two-Dimensional Numerical Simulation on Bubble Growth in Microchannel Boiling Flow

Abstract In this paper, a gradient constraint algorithm is proposed to study the boiling flow mechanism of lithium bromide solution in microchannels. The numerical results obtained using this method demonstrate good agreement with the experimental results. In this study, the growing process of a single refrigerant bubble and the merging of two lateral bubbles in a two-dimensional microchannel were examined. The impact of various factors, such as wall superheat, Reynolds number, surface tension, and double bubble merging on wall heat transfer were investigated. The results show that increases in both wall superheat and inflow Reynolds number improve the heat flux at the heated wall. The effects of changes in surface tension on the heat flux at the heated wall surface differ in the pre- and post-bubble growth periods. The algorithm is still able to keep the interface clear and sharp during multi-bubble merging, and it is found that multi-bubble merging also improves the heat flux at the heated wall.