This paper studies the hydrodynamic characteristics of submersible under the interference of seabed sand wave topography.

Based on the computational fluid dynamics (CFD) method, the process of submersible passing above a seabed sand wave is simulated in the STAR-CCM+ software using the overset grid method, and the evolution of the resistance coefficient and lift coefficient during the process is calculated.

The results show that when the submersible navigates near the seabed, interaction forces act on it. When the bow moves near the wave crest, the maximum negative lift occurs, and when the stern moves near the crest, the maximum resistance occurs. The different surface pressure distribution rules of submersible at different speeds lead to different evolution rules of the lift coefficient. The smaller the H/D, the more significant the influence of the seabed sand wave on the resistance and lift force of the submersible. When H/D > 5, the influence of the seabed sand wave on the resistance and lift force of the submersible can be ignored.

The results of this study provide valuable references for the safety and maneuverability of submersibles.