Numerical simulation of hydrodynamic planar motion mechanism test for underwater vehicles

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2014
Can, Mustafa
Several captive tests, such as; PMM (Planar Motion Mechanism), RA (Rotating Arm), straight-line towing tests and CMM (Coning Motion Mechanism) can be conducted to obtain hydrodynamic coefficients or maneuvering derivatives that are necessary for system simulation of AUVs (Autonomous Underwater Vehicles). Development of computer technology provides an opportunity to solve flow problems by using CFD (Computational Fluid Dynamics). Therefore modeling hydrodynamic tests by using CFD methods is another option to obtain hydrodynamic coefficients. In this thesis, CFD modelling techniques are developed to simulate towing tests, rotating arm tests and planar motion mechanism tests. These test scenarios are modeled by using CFD methods. Commercial flow solver FLUENT is used to solve these flow problems. Straight-line towing tests are simulated for DARPA (Defense Advanced Research Projects Agency) and UK Natural Environment Research Council’s Autosub test-case models. Rotating arm and planar motion mechanism tests are simulated for Autosub test-case model. Rotating arm tests are simulated for constant angular velocity and constant angular acceleration. Then two different motions are simulated in the scope of PMM studies. FLUENT user defined functions are used for analyses that mesh motions are needed. Analyses results are compared with experimental data available in literature.

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Citation Formats
M. Can, “Numerical simulation of hydrodynamic planar motion mechanism test for underwater vehicles,” M.S. - Master of Science, Middle East Technical University, 2014.