A Nonlinear Model for Oscillating Water Column Analysis, Design and Control

A model for the energy exchanges involved in OWC power-plants is proposed. The model is using data series generated by numerical codes developed on the basis of relative physical principles. The ocean wave field and the oscillating water column are modeled according to linear water wave theory as a waveguide excited at both ends. The thermodynamic process inside the chamber is modeled with a controlvolume approach. Then by applying identification techniques for linear and nonlinear systems, the corresponding operator representations are obtained in the frequency domain. A closed-loop is finally constructed which may find use in analysis and synthesis of OWC systems.

[1]  D. V. Evans,et al.  Wave-power absorption by systems of oscillating surface pressure distributions , 1982, Journal of Fluid Mechanics.

[2]  Chiang C. Mei,et al.  Scattering of surface waves by rectangular obstacles in waters of finite depth , 1969, Journal of Fluid Mechanics.

[3]  D. Evans,et al.  HYDRODYNAMIC CHARACTERISTICS OF AN OSCILLATING WATER COLUMN DEVICE , 1995 .

[4]  S. Neelamani,et al.  On the efficiency of wave energy caissons in array , 1997 .

[5]  H. Barlow.  Surface Waves , 1958, Proceedings of the IRE.

[6]  Paulo Alexandre Justino,et al.  OWC wave energy devices with air flow control , 1999 .

[7]  C. Mei.  The applied dynamics of ocean surface waves , 1983 .

[8]  N. Xiros,et al.  Analysis of Coupled Electromechanical Oscillators by a Band-Pass, Reduced Complexity, Volterra Method , 2005 .

[9]  J. Falnes.  Ocean Waves and Oscillating Systems: Linear Interactions Including Wave-Energy Extraction , 2002 .

[10]  D. V. Evans,et al.  Complementary approximations to wave scattering by vertical barriers , 1995, Journal of Fluid Mechanics.

[11]  Gerassimos A. Athanassoulis,et al.  A consistent coupled-mode theory for the propagation of small-amplitude water waves over variable bathymetry regions , 1999, Journal of Fluid Mechanics.

[12]  A. F. de O. Falcão,et al.  Stochastic modelling of OWC wave power plant performance , 2002 .

[13]  W. Rugh.  Nonlinear System Theory: The Volterra / Wiener Approach , 1981 .

[14]  A. Falcão,et al.  Wave-power absorption by a periodic linear array of oscillating water columns , 2002 .

[15]  Johannes Falnes,et al.  Surface wave interactions with systems of oscillating bodies and pressure distributions , 1985 .

[16]  J. Kestin.  A Course In Thermodynamics , 1979 .

[17]  A. Falcão.  Control of an oscillating-water-column wave power plant for maximum energy production , 2002 .

[18]  D. V. Evans,et al.  The Oscillating Water Column Wave-energy Device , 1978 .

[19]  Chiang C. Mei,et al.  Radiation and scattering of water waves by rigid bodies , 1971, Journal of Fluid Mechanics.