Hydrodynamic Drag on Bottom-Mounted Smooth and Rough Cylinders in Periodic Flow
Abstract
The in-line and transverse forces acting on smooth
and sand-roughened circular cylinders placed on a plane
boundary (with no gap) in a sinusoidally oscillating
flow in a U-shaped vertical water tunnel have been
measured. The drag and inertia coefficients for the
in-line force have been determined through the use of
the Morison's equation and the Fourier analysis. The
transverse force has been analyzed in terms of its
maximum and minimum values, root-mean-square values,
and the time it remains above a fraction of its
maximum. The results have been presented as a function
of the Keulegan-Carpenter number and the frequency
parameter β=D²/ѵT.
Description
11th Annual Offshore Technology Conference (OTC) in Houston, Tex., April 30-May 3, 1979