MS Thesis R. Hager - Hawaii National Marine Renewable Energy ...

the percentage difference between the normalized force as the wave impinges body 1 at 0°and 180° at T = 1 sec is 6.13%. Where percentage difference is:( x y)Percent _ Difference ( x y) 2 Note these conclusions are restricted to the assumptions made that the waterline crosssectionalarea and the draft remain constant rather than the submerged volume remainingconstant. A smaller draft corresponds to larger excitation forces and greater powerabsorption (Backer, 2009). A smaller waterline cross-sectional area corresponds to a smallerhydrostatic resorting coefficient, and thus results in resonance occurring at a lower naturalfrequency, affecting the power absorption efficiency (Backer, 2009). The submerged volumewill also have an effect on the hydrostatic restoring coefficient, and thus on the frequency atwhich resonance occurs. Thus, there is a trade-off in whether to keep the waterline crosssectionalarea or the submerged volume constant. Future research should be done to furtherexplore this issue.77