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The oceans contain abundant natural resources, development and utilization of marine resources, has a very important significance to human survival and development, underwater robots is an important means of understanding of the sea, the development of marine essential. Underwater robot is an important branch - autonomous underwater vehicle (AUV), because of its adaptability to environment, a large range of activities, many advantages such as ease of use, has gradually become a hot area of ??research today. In this paper, based on the technical specifications of the design task book, on the basis of the first-generation open-frame AUV completed the structural design of the second-generation AUV prototype part involved, including pressure-resistant cabin design, promoting design is arranged, camera distance adjustment system design, the overall layout and structure of the material choice. Addition in view of the complexity of the AUV the work environment, while the the Withstand cabin wall thickness design for the overall security of the AUV play a crucial role, the pressure bulkhead thick the detailed design, specific methods: discriminant cylinder attribute, select the empirical formula, the spreadsheet design calculations, then use COSMOSWorks software static analysis, draw analyze images, the intensity of checking to ensure the reliability of the withstand voltage compartment security and AUV design . In order to better study the the AUV running resistance and flow, this choice of CFD software FLUENT hydrodynamic analysis work. In this paper, the design of AUV AUV carries its own energy limited, so in order to improve energy efficiency, streamlined structure, the structure through streamlined shroud housing. In order to maximize the reduction of energy loss, the shroud shell shape optimization design. Identified on the basis of the existing framework of structural design required to meet the basic size, different combinations of transition in the head and tail through streamlined and semicircle, forming four shroud model, and then use FLUENT four models simulation, draw their resistance and drag coefficient, by comparing models between different resistance changes, and the impact of the comprehensive model size, select the optimal model complete AUV shroud optimal design. This completes the AUV virtual prototype design. AUV designed three-dimensional hydrodynamic simulation, the simulate AUV viscous flow field around. First, five different grid model simulation, respectively, in the three turbulence models, calculated value with the empirical formula of comparative analysis, and considering the computing speed and other factors, to draw the best grid model with the best turbulence computational model, and as a follow-up simulation of the basic conditions. Then were different running speed, depth, different Reynolds numbers AUV run analysis, come to the viscous resistance of the AUV running, pressure drag and total drag of drag coefficient, AUV surface pressure distribution and the flow field pressure and velocity distribution of a number of hydrodynamic characteristics, in addition to the the hydrodynamic the AUV heave movement. The results prove that the computer simulation has a certain value in AUV hydrodynamic characteristics of the data from these studies can provide a reference for the AUV further research and experimental analysis.
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