Numerical study of turbulent flow boiling heat transfer in structured cooling channels using lattice Boltzmann method with advanced outlet boundary conditions

This study investigated the application of the lattice Boltzmann (LB) method to simulate turbulent flow boiling in structured cooling channels. The simulation used a central moment-based pseudopotential LB model with advanced characteristic boundary conditions to address numerical instabilities associated with turbulent multiphase flow. This approach ensures prolonged stability, facilitating the accurate modeling of complex flow boiling dynamics. The simulation results revealed that structured cooling channels considerably enhanced thermal performance, achieving a 27.3% increase in critical heat flux compared to flat channels. This improvement is induced by the fin structure of structured cooling channel, which makes heat distribution and promotes lower local wall heat flux compared with incident heat flux. Moreover, the simulations showed that fin structures manage bubble detachment more effectively, thereby enhancing heat transfer during the phase-change process. The study suggests that advanced outlet boundary conditions are crucial in stabilizing simulations for fin-structured channels, and the findings provide significant insights into heat dissipation mechanisms in high-heat-flux applications.