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Twenty-First Symposium on NAVAL HYDRODYNAMICS
Free surface flow visualisation
Figure 36
Point vortices. Re=150. Case 14
Figure 37
5
Conclusions
Results have been presented of both 2-D and 3-D computations of the vortex wake behind a cylinder towed through waves. The computations are at a Reynolds number of 150. A survey of the changing wake patterns as a function of the wave parameters is presented. These data are in good qualitative agreement with both data in the literature on vertical cylinders in steady flow undergoing in-line oscillations, and surface flow visualisation data conducted in the Department of Aeronautics wave flume. A 3-D computation proved computationally expensive, but demonstrated reasonable agreement with the 2-D computations, and provides useful experience for future research in this direction. A 3-D computation of flow past a linearly tapered cylinder in a steady current is also presented. The data show the spanwise cell formation observed in flow visualisation experiments carried out by the authors on an identical geometry.
6
Acknowledgements
This work was supported by the Office of Naval Research under contract No. N00014–90-J-4122.
7
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