Effect of Forward Speed on the Roll Damping of Three Small Fishing Vessels

An extensive experimental program has been carried out to estimate roll damping parameters for three models of fishing vessels having different hull shapes and moving with forward speed. Roll damping parameters are determined using a novel method. This method combines the energy method and the modulating function method. The effect of forward speed, initial heel angle and the natural frequency on damping is discussed. A modification of Ikeda’s formula for lift damping prediction is suggested. The modified formula produces results which are in good agreement with the experiments.