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Abstract

An autonomous underwater vehicle (AUV) is an unmanned (i.e. without requiring input from an operator) underwater self-propelled robot. They are a part of a larger class of unmanned underwater vehicles of which another part is Remotely Operated Vehicles (ROVs). AUVs are programmed at the surface, then navigate through the water on their own and collect data as they go. As against AUVs, ROVs remain tethered to the host vessel and controlled and powered by an operator through an umbilical. In this paper investigation of the hull shape of the AUV has been design based on the minimisation of Coefficient of Drag. The present AUV model has been prepared considering 2D axisymmetric geometry in ANSYS Fulent-16. As the computer technology developed very rapidly, computational fluid dynamics (CFD) is now widely applied to analysing AUV hydrodynamic performance. In our venture, we are using SolidWorks for modelling and ANSYS for simulation. The CFD analysis provides better drag estimates over the empirical ones and also provides accurate stimulations of the flow around the vehicles. The paper is configured in two phase. Initially, the investigation done in shape of the nose and tail with unstructured meshing with SST k-ω model by comparing different types of shape with their corresponding Coefficient of drag value. The optimized shape is then used to produce a 3D body, which is subjected to structural analysis in ANSYS 16.0. Stress concentration is inspected for varying depth of the submerged AUV.

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Keywords

Autonomous Underwater Vehicle(AUV), Coefficient of Drag, SST k-ω model, Simple Scheme