Initial investigation of ship resistance at river mouth area

Abstract

Lateral drift is one of the phenomenons when ship operates in open sea. It is possibly occurs due to waves and/ or wind and/ or current. In this study, the phenomenon of lateral drift effect onto ship resistance is investigated. As the early stage of this research, the study is focused on ship resistance prediction in calm water condition. In executing this research, the principle that will be used is by using the selected ship resistance prediction method as a basis. Any parameters in the formula which are influenced by drift effect will be reviewed. In this study, two cases are considered, namely Case 1 and Case 2. For Case 1 it is mainly considered the factor of ship velocity influencing the total resistance with lateral drift effect. For Case 2, other parameters are taken into account, which is length and breadth, as well as ship velocity. Due to the presence of drift angle, the velocity is separated into longitudinal and lateral component, and consequently, the process of total ship resistance determination is solved separately in longitudinal and lateral as well. At the end, the resultant of total ship resistance is determined using trigonometric solution. Thus, this becomes the total ship resistance, RTOTAL with lateral drift effect and it varies with the variation of drift angles. This principle of investigation considerably as an initial step in gaining some insights about this complicated problem. The result indicates that there is significant difference of total ship resistance, RTOTAL produced with lateral drift effect, comparing to the condition without lateral drift effect.