Effects of Bubbles Sizes on the Phase Distributions in a Bare Rod Bundle Channel

Abstract In order to clearly understand the phase distributions, the gas-liquid two-phase flow in a 5 × 5 bare rod bundle channel was numerically studied based on the Euler-Euler two fluid model with the CFX commercial software. In the two-phase bubbly flow simulation, the interfacial forces between gas-liquid phases including interfacial drag, lift, turbulent dispersion, wall lubrication, and virtual mass were considered. The experimental data was used to verify the numerical models. Different bubble diameters and MUSIG models in rod bundle channel were used in the numerical simulations, and the effects of bubble diameters on the phase distributions were carefully analyzed. It was found that the overall flow resistance increases with the larger bubble diameters. The bubble size significantly affects the void fraction distributions. The bubbles with the greater diameters tend to accumulate in the center of the rod bundle channel, while the bubbles with small diameters tend to appear in the rod bundle walls.