Presentation Title: Geometric Optimization of a 2-D Heaving Body for Power Absorption Discipline: Mechanical Engineering School: University of Hawaii at Manoa Presentation Type: Poster Presentation Abstract: Geometric Optimization of a 2-D Heaving Body for Power Absorption 1 1 1 R.E. Hager ; M. Teng, PhD ; and N. Fernandez 1 University of Hawaii at Manoa, Honolulu, Hawaii The focus of this research is to advance the work related to optimizing the geometry of two-dimensional wave-buoy interactions. This was done through measuring wave excitation force on the buoy models and radiated wave amplitudes at infinity along the length of a wave flume. Unique from previous studies, this project utilizes an alternative method to measure power absorption efficiency. The experimental tests are based on the following equations derived from the potential wave theory: Equation 1.  

  

Equation 2.   

 

     

 

Currently, three of 8 different buoys have been tested under various wave conditions, which satisfy linear potential theory. The excitation force on the fixed buoy from an incident wave was measured in a flume with a load cell to calculate the radiated wave’s amplitude at positive infinity along the length. Rotating the buoy model 180 degrees yielded the radiated wave’s amplitude at negative infinity. Thus, power absorption efficiency was be calculated based on the measured excitation force data. Since the buoy’s geometry is the varying parameter, the added mass, damping, and spring coefficients were kept constant. This was attained by fixing the draft, waterline cross-sectional area, and wave conditions. Of the three tested shapes, the concave face was the most efficient at the experimental depths, 10.5 and 11 in. Further research would include testing a three-dimensional buoy with a larger wave flume. Rather than rotating the buoy 180 degrees, it would be rotated incrementally 360 degrees.

Presenter: Nelson Fernandez Tribe: Native Hawaiian Primary Email: nelsonif@hawaii.edu Biography Nelson Fernandez was born and raised in Hawaii. With paradise as his home it was no wonder that science fascinated him and even from an early age he showed a particular curiosity and predisposition for the world around him. Nelson’s college career has helped him focus his passions as a mechanical engineering undergraduate student. Engineering coupled with his love of the Hawaiian culture has helped him to live in both worlds. He is a member of the Native Hawaiian Science and Engineering Mentorship Program, SACNAS, and AISES. He plans to give back to these programs for the help and guidance.

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2011 National Conference Student Research Abstracts
2011 National Conference Student Research Abstracts

A comprehensive list of the student research topics that will be presented at the AISES 2011 National Conference