A Prediction Method of Vertical Lift Component in Roll and Heave Damping

Abstract

The measured heave and roll dampings of high-speed planning craft by forced oscillation experiments demonstrate that the predicted dampings singnificantly underestimate the experimental ones. These may be because the effect of the vertical lift force acting on the craft on these dampings is not taken into account in the prediction methods. Methods to predict the contributions of the vertical lift coefficient of a craft running in steady speed which depends on time and rise of it, the roll, the heave and the coupling damping from heave to pitch can be predicted by the methods. It is confirmed that predicted results are in fairly good agreement with measured ones.