A unified FSI framework for modeling liquid sloshing and baffle suppression in the elastic tank

The dynamic and highly nonlinear nature of liquid sloshing in liquefied natural gas (LNG) tanks necessitates accurate numerical modeling to ensure structural integrity and operational safety during maritime transport. However, existing studies often overlook detailed stress and strain distributions within tank walls, which limits the assessment of structural reliability. Additionally, traditional fluid–structure interaction (FSI) approaches typically adopt separate solvers for fluid dynamics and structural mechanics, leading to data transfer errors and interpolation inaccuracies. To address these challenges, this study employs a unified smoothed particle hydrodynamics (SPH) framework for simulating liquid sloshing and its interaction with elastic tank structures. The effects of single- and multi-resolution schemes, as well as single- and multi-phase formulations, are systematically analyzed to assess their influence on numerical accuracy and computational efficiency, through validation against experimental data. The results demonstrate the reliable precision of the proposed multi-phase and multi-physics FSI model in predicting free-surface elevation, pressure distribution, and structural deformation. Furthermore, the study explores the effectiveness of various baffle configurations in mitigating sloshing-induced forces and structural deformations, providing insights into their role in mitigating hydrodynamic loads on tank structures.