Experimental Investigation of Irregular Wave Cancellation Using a Cycloidal Wave Energy Converter

Abstract

The ability of a Cycloidal Wave Energy Converter (CycWEC) to cancel irregular deep ocean waves is investigated in a 1:300 scale wave tunnel experiment. A CycWEC consists of one or more hydrofoils attached equidistant to a shaft that is aligned parallel to the incoming waves. The entire device is fully submerged in operation. Wave cancellation requires synchronization of the rotation of the CycWEC with the incoming waves, as well as adjustment of the pitch angle of the blades in proportion to the wave height. The performance of a state estimator and controller that achieve this objective were investigated, using the signal from a resistive wave gage located up?wave of the CycWEC as input. The CycWEC model used for the present investigations features two blades that are adjustable in pitch in real time. The performance of the CycWEC for both a superposition of two harmonic waves, as well as irregular waves following a Bretschneider spectrum is shown. Wave cancellation efficiencies as determined by wave measurements of about 80% for the majority of the cases are achieved, with wave periods varying from 0.4s to 0.75s and significant wave heights of Hs 20mm. This demonstrates that the CycWEC can efficiently interact with irregular waves, which is in good agreement with earlier results obtained from numerical simulations.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 2012
Accession Number
ADA563271

Entities

People

  • Casey Fagley
  • Marcus Romer
  • Stefan G. Siegel
  • Thomas Mclaughlin

Organizations

  • United States Air Force Academy

Tags

DTIC Thesaurus Topics

  • Air Force
  • Cancellation
  • Converters
  • Data Analysis
  • Deep Oceans
  • Deep Water
  • Energy
  • Estimators
  • Measurement
  • Ocean Waves
  • Renewable Energy
  • Seabed
  • Simulations
  • Solar Energy
  • Water
  • Wave Power
  • Waves

Readers

  • Chemistry (specifically Chemical Fluorescence)
  • Coastal Oceanography
  • Marine Hydrodynamics