Multi-Physics Simulation Study on Slope Water Entry of Wheeled Amphibious Vehicles

Abstract

Accurate prediction of the dynamic response of wheeled amphibious vehicles during slope water entry is critical for operational safety, as this process involves intense gas–liquid–solid multi-phase coupling with highly transient and nonlinear characteristics. This paper establishes a bidirectional multi-physics co-simulation framework integrating STAR-CCM+ (version 2506) and ABAQUS (version 2024). For the fluid domain, the Reynolds-averaged Navier–Stokes (RANS) equations are solved in conjunction with the Realizable k-ε turbulence model, the volume of fluid (VOF) interface capturing method, and the over-set mesh technique. For the solid domain, rigid body dynamics and contact mechanics formulations are employed, with hull–slope contact constraints explicitly incorporated. Closed-loop coupling between the two domains is achieved via time-step-synchronized data exchange. The proposed method is validated against water entry experiments, with favourable agreement between numerical predictions and experimental measurements. Parametric analysis quantifies the effects of slope angle and initial entry velocity on peak submergence depth, pitch response, and slamming loads. By explicitly incorporating hull–slope contact and friction into the bidirectional coupling process, the proposed framework offers a model- and condition-specific numerical basis for preliminary operating condition screening and safety assessment during cross-medium transition; a generally validated operational envelope remains to be established in future work.