A Numerical Study to Predict Added Resistance of Ship in Irregular Waves

摘要

Fuel consumption of ship has been of great interest due to the reinforced environmental regulations. Estimation of fuel consumption requires calculating the added resistance in actual irregular waves. However, most of relevant researches remain in regular wave since nonlinear interaction is hard to be included in numerical computation. In this paper, the added resistance in irregular head sea has been investigated using Reynolds-averaged Navier–Stokes based Computational Fluid Dynamics. The results were compared to those of the model tests conducted in Samsung Ship Model Basin. In the simulation, the irregular waves were generated by the linear superposition of a number of incoming wave components. Since the computation times are highly increased when a large number of waves are used, total time window was divided into a number of partitions, and irregular waves were continuously generated by overlapping the neighboring windows. Three degrees of freedom were considered for ship’s motion: heave, pitch and surge. Motion responses from the computation show fairly good agreement to those from the model test. In addition, the simulation predicts the added resistance in the similar level of accuracy to the experiment. The stepwise analysis is made and key findings are discussed.