Free surface flow visualisation
Point vortices. Re=150. Case 14
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.
This work was supported by the Office of Naval Research under contract No. N00014–90-J-4122.
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