On the Effect of Wind around the Pier upon the Course-keeping of Ship

Aerodynamic data of yawing moment and swaying force of ship in wind passing through by the pier of the bridge spanning over the ship's passage were obtained by the wind tunnel with water tank test. Substituting these data in the equations of motion of ship as the external disturbance, the course deviation and the transverse movement of ship were computed with respect to the ship's course and the relative position of the pier. The ship's trajectories are shown in Figs from 8-1 to 8-8 as the parameters of the ship's course, wind direction and configulation of the pier respectively. Results indicate that the minimum clearance of the ship's course to the pier face will be generally required a distance of the ship's length for passing over in safety. Moreover, it is reasonably required for reducing the sheer flow of wind around the pier by improving the sectional configulation from the viewpoint of pier construction to decrease the wind effect on the steering bias of ship.