12 / 2025-03-22 09:02:59

Phase-field lattice Boltzmann method for boiling simulation considering real fluids under real operational conditions

lattice Boltzmann method,Nucleate boiling,Real fluids,Saturated boiling

The liquid-gas phase-change process is an important phenomenon that can be found in several applications in the industry. Power generation and refrigeration systems are directly dependent on evaporators and boilers for their operation. Consequently, the ability to model this process is of utmost importance for the design and development of these devices. In terms of phase-change simulations, the lattice Boltzmann method (LBM) has gained attention because of its ability to deal with complex flows, such as multiphase flows. However, there are few works in the literature dealing with real fluids in the phase-change process, even fewer using the phase-field-based LBM. Then, in this work we propose an Allen-Cahn-based LBM for simulating liquid-gas phase-change processes considering a real fluid under experimental operational conditions. For this task, we based our model on the phase-field LBM previously proposed by [1], with modifications to account for the thermal phase change process and the dimensional approach of [2], which allows the direct use of physical units, facilitating the employment of real fluids. The model is first tested in the Stefan problem considering the HFE7100 as a working fluid, and the numerical solution is compared to the analytical one. Next, a single bubble under pool boiling from a cavity is simulated and the results are compared to the experimental data obtained by the authors themselves with the procedure described in [3]. The numerical solutions showed very good agreement with both the analytical solution (for the Stefan problem) and the experimental data (for the single bubble), evidencing the capability of the LBM to deal with phase-change problems.