Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8059355 | Applied Ocean Research | 2017 | 12 Pages |
Abstract
This paper investigates the performance of a small axisymmetric buoy under wave-by-wave near optimal control in surge, heave, and pitch modes in long-crested irregular waves. Wave prediction is obtained using a deterministic propagation model. The paper describes the overall formulation leading up to the derivation of the feedforward control forces in surge and heave, and the control moment in pitch. The radiation coupling between surge and pitch modes is accounted for in the model. Actuation is relative to deeply submerged reaction masses. Heave oscillations are constrained by the swept-volume limit. Oscillation constraints are also applied on the surge and pitch oscillations. The paper discusses time-domain simulations for an irregular wave input with and without the present control. Also discussed are results obtained over a range of irregular wave conditions derived for energy periods from 7Â s to 17Â s, and a significant wave height of 1Â m. It is found that, while the gains in power capture enabled by the present control are significant, the actuation forces are also very large, given the small size of the buoy. Further, due to the small size, heave is found to be the dominant contributor to power capture, with relatively modest contributions from surge and pitch.
Related Topics
Physical Sciences and Engineering
Engineering
Ocean Engineering
Authors
Umesh A. Korde, Jianyang Lyu, Rush D. III, David G. Wilson, Giorgio Bacelli, Ossama O. Abdelkhalik,