| Free oscillation tests using three types of moored fishing boats were performed to acquire the damping coefficient of their surging motion. The damping coefficient of a heavier boat was found to be much small due to its strong inertial force. It was also found that the viscous drag coefficient estimated from the damping coefficient was about 0.5 in the case of 5 to 20 gross tonnage. The characteristics of the mooring ropes used on the boats were also investigated from a tension strength test. The tension strength of the mooring ropes used over long periods had much decreased due to deterioration. The damping coefficients、 the viscous drag coefficients and the characteristics of the mooring ropes acquired in this study are applicable to estimating proper parameters for the numerical simulations of dynamics of moored fishing boats. |
