Loading on a vertical cylinder in multidirectional waves
- City Univ., London (United Kingdom). Ocean Engineering Research Center
- National Research Council, Ottawa, Ontario (Canada). Institute for Marine Dynamics
This paper presents laboratory measurements of local and total loading on an isolated vertical cylinder in irregular unidirectional and multidirectional waves. Maximum Keulegan-Carpenter numbers in individual waves were about 16, and maximum reynolds numbers about 3 {times} 10{sup 4}. It is shown that in these conditions, existing theoretical and numerical models underestimate the reduction in loading on a cylinder due to wave spreading. Besides the changes that are predicted when Morison`s equation is used with constant coefficients, there are hydrodynamic influences that contribute further force reductions. Comparisons with Dena`s (1977) hybrid approach suggest that in the present conditions these reductions are in the region of 3 and 6 percent for a spreading function cos{sup 2s} {theta}, with s = 8 and s = 2, respectively. Larger reductions can be expected at higher Keulegan-Carpenter numbers, though scale effects are likely to become more important in the drag-dominated regime.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 118772
- Journal Information:
- Journal of Offshore Mechanics and Arctic Engineering, Journal Name: Journal of Offshore Mechanics and Arctic Engineering Journal Issue: 3 Vol. 117; ISSN 0892-7219; ISSN JMOEEX
- Country of Publication:
- United States
- Language:
- English
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