Hydrodynamics Design Considerations for Underwater Vehicles

Abstract

Underwater vehicles, such as Unmanned Underwater Vehicles (UUVs) and submarines, require a number of considerations during their design, such as operational requirements including range, speed and profile; weight balance; structural integrity; construction capability; stealth including acoustic and visual signatures; platform efficiency; sensors fit; payload; and costs. One of the major aspects that influences the final design is the hydrodynamic characteristics of the hull and the influence of the appendages. Although this cannot be considered in isolation, the hydrodynamics will dictate to a large extent the shape of the vehicle?s hull and casing, the location and shape of the fin or sail, and the appendage configuration. The operational and manoeuvring performance of the platform, both submerged and surfaced, is heavily dependent on the hydrostatics, hydrodynamics, and seakeeping capabilities of the vehicle. They dictate how the vehicle reacts to internal and external influences during normal and extreme manoeuvers. These requirements also influence the shape, location, and the configuration of the forward and aft control surfaces, as well as the proplusor configuration, as the flow into the latter affects its hydrodynamic performance and acoustic signature. In addition to the vehicle?s performance, the flow past the hull, appendages, and propulsor contribute to flow noise that makes the vehicle susceptible to detection as well as affecting the efficiency of the on-board sensors. Thus, the vehicle and its external appendages need careful hydrodynamics consideration during the design and operational phases to ensure that the platform will meet its design objectives and maintain them throughout its lifecycle.