A coupling method of least squares fit interface reconstruction and isoAdvector for plunging breaking waves

During wave breaking, the free surface undergoes intense deformation, generating numerous bubbles and droplets. The dynamic behavior of the deforming interface critically influences overall system performance. To accurately capture the large deformation of such complex geometries, this study proposes the plic-LSFIR reconstruction scheme, which combines the least-squares fit interface reconstruction (LSFIR) with the excellent volume conservation and sharp interface representation of the isoAdvector framework. Through a locally stable convergence strategy, it achieves higher robustness and greater accuracy in predicting interface evolution in complex flow fields. The method was verified through comparison with a series of benchmark cases. Quantitative assessments demonstrate that in most cases, plic-LSFIR achieves higher interface prediction accuracy than other reference methods. Furthermore, by simulating wave overturning over a submerged bump, the capability of the plic-LSFIR method to capture air-water mixing phenomena is demonstrated. The overall wave breaking process and key events are identified from the simulated wave field and verified against publicly available experimental data. These results indicate that the plic-LSFIR method offers a robust and accurate framework for the simulation of two-phase flows with large interface deformations.