Abstract
The unified theory is enhanced to account for the wave diffraction in the direction of ship's logitudinal axis near the ship ends and to solve the surge-mode radiation problem. Three-dimensional and forward-speed effects are taken into account as in the original unified theory, by solving the integral equation for the outer source strength along the ship length. Numerical examples are shown for the surge added-mass and damping coefficients, pressure distributions, wave-exciting forces, and added resistance in head waves; these are compared with experimental data and corresponding results of other calculation methods. It is confirmed that the effects of wave diffraction near the ship ends are properly accounted for in the present method, which is pronounced in the prediction of the added resistance. The importance of the cross-coupling effects between surge and pitch is also noted in the surge motion calculations.
