On Calculation Method of Ship Maneuvering Motion at Initial Design Phase

This paper presents a practical method to predict the characteristics of the ship maneuvering motion at the initial design phase. Supposing that the principal particulars of ship hull, propeller and rudder are given at the phase of the ship initial design, an attempt is made to calculate the maneuvering motion utilizing those principal particulars as basic input data. The mathematical model which describes the ship maneuvering motion is based upon the coupled equations of surge, sway, yaw, heel and number of propeller shaft revolution shown in Eq. (1). Computations are made for seven typical merchant ships covering various kinds and sizes of ships shown in Table 1. In order to examine the validity of the calculation method of this paper for wide range of maneuvering motion characteristics, the computed results are compared with the results of the full scale trial for three kinds of typical characteristics, namely turning motion with rudder angle of 35°, 10°-10° zigzag maneuver response and steady turning performance. Both the computed and the full scale trial results are in satisfactory agreement generally for various kinds and sizes of ships, and for wide range of maneuvering motion characteristics, as shown in Figs. 530. It can be concluded that the calculation method proposed in this paper is very useful and powerful for the prediction of the characteristics of the ship maneuvering motion at the initial design phase.