Impact of trim on added resistance of KRISO container ship (KCS) in head waves: An experimental and numerical study

In this study, added resistance and motion responses of KRISO Container Ship (KCS) were evaluated experimentally and numerically in six different trim angles. A series of towing tank experiments were performed for six different trim angles at design speed in calm water and regular head waves. The ship motions and added resistance were measured for several wavelength conditions considering short and long wave ranges with wave steepness of 1/60. Next, computations of the towed model in calm water and waves were performed using Unsteady Reynolds-Averaged Navier-Stokes (URANS) CFD and 3-D potential methods. Effects of trim angles on added resistance were analysed and results concerning the performance of the vessel at different trim angles were plotted. Experimental and numerical results for the heave and pitch motions and the added resistance were compared and URANS CFD simulation results showed good agreement with the experimental data for the ship in head waves. Also, the results were compared to those from potential theory and range of trim and wave conditions were identified for the application of rapid linear potential flow method. •Heave and Pitch motion RAOs were predicted at different trim angles and changes are compared to level trim.•Added resistance at different trim angles were predicted and changes in optimum trim were discussed.•Numerical results were compared with EFD as validation study.•Potential flow method capabilities to predict added resistance at trimmed conditions were discussed.