Hydrodynamic shape genealogy for teardrop-shaped Autonomous Underwater Vehicles

More diverse marine tasks and longer range water missions require the hydrodynamic shape, viz. hull shape, of Autonomous Underwater Vehicles (AUVs) for both efficient design and least resistance. Therefore a systematic design for the hydrodynamic shape of AUVs is needed and necessary to meet the various requirements. In the present work, a hierarchical classification for the hull shape of AUVs was proposed according to the shape characteristics of the main hull of AUVs. Focused on the teardrop-shaped AUVs, hydrodynamic drags of a series of hull shapes were computed and analyzed using the computational fluid dynamics (CFD) simulation method with different hull shape parameters and Reynolds numbers (Re). The general mathematical model of volumetric coefficient of hydrodynamic drag and hull shape parameters, i.e., length diameter ratio (L/D), nose length diameter ratio (Ln/D), tail length diameter ratio (Lt/D) and Reynolds number (Re), was established and verified. The present work makes it possible to efficiently design the hull shape with minimum drag.