A study on berthing and unberthing of a single-shaft ship with a bow thruster

Abstract

In this study, the berthing and unberthing performances of a single-propeller and single-rudder inland container ship with a flapped rudder and bow thruster were investigated using free-running model tests. A navigation method was used for the tests to adjust the bow thruster, so that the heading remained parallel to the pier and the ship berths or unberths while sailing in oblique conditions. As a result, the proposed method enables the target ship to berth or unberth in shallow water with h/d=1.5, where h is the water depth and d is the ship draft. Such a free-running test using the navigation method is useful for evaluating the berthing and unberthing performance of single-shaft ships with a bow thruster. In addition, a bow thruster impeller revolution controller was incorporated into the maneuvering simulation model proposed by the authors, and berthing calculations were performed. The calculation results were compared with free-running test results for validation. These results are consistent with the free-running test results with practical accuracy.