Session: VIB-02-02 Nonlinear Systems, Phenomena and Energy Harvesting

Paper Number: 69977

Start Time: August 17, 02:10 PM

69977 - Numerical Analysis and Parameter Optimization of a Portable Two-Body Attenuator Wave Energy Converter 

Easily portable, small-sized ocean wave energy converters (WEC) may be used in many situations where large-sized WEC devices are not necessary or practical. Power maximization for small-sized WEC devices amplifies challenges that are not as difficult with large-sized devices, especially tuning the device’s natural frequency to match the wave frequency and achieve resonance. In this study, power maximization was performed for a small-sized, two-body attenuator wave energy converter. The study was performed for three different buoy geometries under regular wave conditions. A simplified two degree-of-freedom model was used. Four different viscous drag coefficients were used for each geometry to demonstrate the effect of drag. For each geometry, the natural frequency was tuned to match the wave frequency by adjusting the body dimensions in order to achieve resonance and maximize power generation. A thin, submerged tuning plate was added to each body to increase added mass without significantly increasing hydrostatic stiffness in order to reach resonance. The BEM solver ANSYS AQWA was used to obtain the hydrodynamic coefficients. Optimal PTO damping was determined numerically through WEC-Sim, giving the maximum power. Based on the study, the highest power can be achieved with the elliptical buoy cross section, which resulted in a maximum power of 23.88 W and capture width ratio of 5.63% under regular waves for a given 0.5m x 1m footprint constraint. The elliptical shape had the highest power absorption when appropriate drag coefficients were used for each shape.

Presenting Author: Lei Zuo Virginia Tech

Authors:

Joseph Capper Virginia Tech
Jia Mi Virginia Tech
Qiaofeng Li Virginia Tech
Lei Zuo Virginia Tech