Fig. 7 Influence of fin angle θf on the added mass coefficients Cv and Cp for: (a) Model 1 (a); (b) Model 2(a). (lf = 0.5L = 0.3 m)
4. CONCLUSIONS
1. For a floating body with complicated configuration, the experimental method presented in this paper provides an effective and convenient technique for calculating the frequency-dependent added mass mh and added mass moment of inertia Iap, no matter it is equipped with fins or not.
2. In addition to the beam/draft ratio (β= b/d) and the area coefficient σ, the fin length lf and fin angle θf are another two important factors affecting the sectional added-mass coefficients of a floating body, Cv and Cp.
3. For a floating body either with or without fins, the sectional added mass coefficient obtained either from the heave-motion tests (Cv) or from the pitch-motion tests (Cp) is a function of the oscillating frequency ωw.
4. For a floating body "without fins", the conventional approach for evaluating its added mass moment inertia from the sectional added mass is available, but this is not true for a floating body "with fins".
5. ACKNOWLEDGEMENTS
The authors wish to thank the financial support of the Committee of Agriculture of Republic of China and experimental help of Messrs. W.I. Chen, P.Y. Shin and L.K. Chiang, etc.
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