| Abstract: | Exploration and economic activities in the ocean environment have steadily increased in recent years, motivating the need for safer, more efficient methods to operate, survey, and gather underwater data. Autonomous Underwater Vehicles (AUVs) are a class of marine vehicles with the potential to greatly impact the ability function and collect data in the oceanic environment. Research has been focused on optimizing AUV hulls modeled after traditional torpedo designs which present a long, slender body of revolution to increase the vehicles range. While this has proven effective, it greatly limits the maneuverability and payload capacity of the vehicle. Recently, the focus has shifted to studying marine life forms as the basis of AUV hull design. It is recognized that marine life forms have the advantage of millions of years of evolution to optimize maneuvering in the dynamic ocean environment. This, coupled with significant advances in Computational Fluid Dynamics (CFD), has created a new opportunity to further improve AUV design. Innovative marine vehicle design exists at the intersection of aquatic properties and mechanical capabilities. Typically, marine life forms which maintain a rigid body while swimming are the easiest to adapt for mechanical design. As a whole, marine life forms mimic many traditional AUV hull characteristics, while also exhibiting a larger optimal fitness ratio range (3-8), a posterior maximum body thickness, and a blunt stern. Following a literature survey, a created hull shape will be tested in OpenFOAMat four Reynolds numbers (3700, 7384, 11076, 14768) to understand the hydrodynamic characteristics. These results are compared to simulations modeling turbulent flow around a sphere at a Reynolds number of 3700. The flow around a sphere serves (i) as a reference hull shape for assessing the hydrodynamic efficiency and (ii) to validate CFD calculations. The selected AUV hull form presents ideal hydrodynamic flow properties at all Reynolds numbers. Due to a low pressure gradient over the body, fluid remained attached along the entire length of the body, effectively reducing the turbulence present in the wake. Additionally, the drag coefficient reduced with increasing Reynolds numbers. The electronic version of this dissertation is accessible from https://hdl.handle.net/1969.1/198068 |
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