An Approximate Calculation of Maneuvering Interaction Forces Between Two Ships (continued)

Abstract

In the present paper, a simplified method for calculating the maneuvering hydrodynamic forces on a ship's hull moving parallel to a single side wall in shallow water is developed using the linear lifting surface theory. Calculated results agree approximately with the experimental results obtained by changing distance between the ship and the wall, and water depth. In order to clarify nonlinear characteristics of hydrodynamic forces on a ship caused by presence of a side wall, a basic calculation concerning hydrodynamic forces on a flat plate wing inclined to wall surface is examined. By using the image method, the calculation is made for the wing inclined at a large angle of attack in the proximity of a wall plane, based on Bollay's nonlinear wing theory. Experimental results indicating unsymmetrical variation of hydrodynamic forces with positive or negative angles of attack, can be explained well by the theoretical values. Furthermore, experiments on interaction forces between two ships were performed by employing slender-body ships. Calculated results obtained through the method, which was used for tnaker-typed ships in the previous paper, agree qualitatively with the experimental results.