Hydrodynamics of a Remora-inspired autonomous underwater vehicle approaching and docking to a benchmark submarine

Autonomous underwater vehicles (AUVs) are applied in a variety of industries to increase the efficiency and safety of maritime operations. Traditional docking and recovery techniques for AUVs, however, can be inefficient. Therefore, the development of a dynamic underwater recovery mechanism for AUVs is now needed. Recent research has investigated the symbiotic relationship between the remora fish and the shark from a hydrodynamic perspective. Numerical simulations have demonstrated that by exploiting the boundary layer and adverse pressure gradient regions around the shark, the resistance experienced by remora fish can be significantly reduced. Inspired by this, an AUV was designed, and numerical simulations were conducted to investigate the impact of various attachment locations. Moreover, simulations were performed to investigate the hydrodynamic characteristics of the AUV during the docking process, specifically when it enters the boundary layer of the submarine and approaches it. The boundary layer flow, which influences the AUV's resistance, can also provide a force that attract the AUV towards the submarine. This research identifies an optimal attachment location and investigates the effects on the AUV when two underwater vehicles of significantly different sizes are in close proximity. It supports further study to develop a dynamic underwater docking operation.