An Approximate Calculation of Maneuvering Interaction Forces Between Two Ships

Abstract

This report deals with an approximate calculation of hydrodynamic forces generated by interactions between two ships which are moving along parallel courses at the same velocity, and hydrodynamic interactions of ships with a bank wall are also examined. With the assumption of the rigid free-surface and infinite water depth, the calculation method is based on the linearized thin-wing theory, using sources distributed over the center plane to represent thickness effects of two ship's bodies. A correction factor for equivalent distance between a ship and a bank wall is introduced to modify the ship breadth effect on the interaction forces, and the value of factor is determined experimentally From the present study, it is clarified that the correction factor is almost constant regardless of ship breadth and the separation distance. When adopting the modification mentioned above, this prediction method gives good qualitative agreement with experimental results for the interaction forces between two tanker-class ships.