There is a growing interest in using unmanned underwater vehicles to perform a large array of tasks that require operation near the surface, and the wave-induced loads experienced by these vessels play an important role in their design and operation. An analytic solution can predict first-order loads on a submerged body using potential flow theory. However, potential flow does not take into account viscous effects, which can also be significant in the hydrodynamic loads experienced. Experimental model tests were performed using a wave generation tow tank, where both potential and viscous effects were acting on a submerged body, at speed, near the surface. Two different geometries were tested to model these submerged bodies. One model was a cylindrical body with hemispheric endcaps. The second model was a cylindrical body with circular, flat-faced endcaps. Experiments on both models were performed to measure hydrodynamic loads for three different speeds over various wavelengths, at two model depths, and for one wave height. The measured loads were then compared and analyzed against the predicted loads from the analytic solution, and the significance of viscous loads was determined.
Kwon, Young W. Klamo, Joseph
Naval Postgraduate School
Master of Science in Mechanical Engineering
Mechanical and Aerospace Engineering (MAE)
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