Numerical Investigation on Interactive Hydrodynamic Performance of Two Adjacent Unmanned Underwater Vehicles (UUVs)

This study investigates the effectiveness of UUV formations during navigation to designated target areas. The research focuses on propeller-equipped UUVs and employs a computational fluid dynamics (CFD) methodology to analyze the hydrodynamic interactions among multiple UUV formations while en route to their targeted exploration areas. Utilizing the relative drag coefficients ((Formula presented.)) and static thrust ((Formula presented.)) as analytical parameters, this paper defines the relative distances ((Formula presented.) and (Formula presented.)) between UUVs within a formation and conducts a comparative analysis of the hydrodynamic performance between individual UUVs and formation configurations. The study establishes correlations between relative distances and the hydrodynamic performance of formations. The findings reveal the following: 1. For both the lead UUV and the following UUV within the formation, the (Formula presented.) heatmaps exhibit two distinct regions: a thrust region and a drag region. Notably, these regions significantly overlap. The maximum (Formula presented.) is 31.23%, while the minimum (Formula presented.) is −20.9%, corresponding to relative distances of (Formula presented.) = 0.12 and (Formula presented.) = 1.5. Conversely, the minimum (Formula presented.) is −12.2%, while the maximum (Formula presented.) is 22.03%, with relative distances of (Formula presented.) = 1.1 and (Formula presented.) = 0.2; 2. An analysis of formation static thrust (Formula presented.) reveals that it can be up to 7% greater than the drag experienced by self-propelled UUVs when relative distances (Formula presented.) and (Formula presented.) are set to 1.1 and 1, respectively. This highlights the enhanced performance achievable through formation navigation. The results presented in this paper offer valuable theoretical insights into the optimal design of relative distances within UUV formations, contributing to the advancement of UUV formation navigation strategies.