1999 Volume 15 Pages 387-392
Wave forces on a vertical cylinder in directional waves have been investigated. Morison equation has been utilized to express the wave force. In directional waves, the effect of the lift force may dominates over the drag and inertia forces when one component of the horizontal water particle motion dominates over the other one. Under such conditions, the Morisone quationc onfirmedt o be less accuratei n estimatingt he wave force. The effect of the lift force, however, becomes less important in estimating the wave force acting on a whole cylinder. This paper shows that the wave force on the cylinder can be evaluated with the drag and inertia coefficients obtained in this study. Moreover, it is confirmed that the wave forces in directional waves, for a given magnitude of the velocity, is larger than that of the uni-directional waves. Thus, effect of the directional spreading should be properly consideredi n the estimatingt he wavef orce.
