A Numerical Study on Correlation Between the Bow Design Parameters and Added Resistance Using the Design of Experiments

In this study, numerical computation was carried out for evaluating the effects of the design parameter variations on the added resistance of Aframax tanker in head seas. The design of experiments (DOE) was used to efficiently conduct the numerical simulations with the hull form variations and save computational resources. A computational fluid dynamics (CFD) code based on the continuity and Reynolds averaged Navier-Stokes (RANS) equation was used for the numerical simulation. The simulation was performed in a short wave condition where the wave length was half of the ship length, which is expected to be most frequent in the vessel operation. Five design parameters of fore-body hull form were selected for the variations: design waterline length (DWL), bulbous bow height (BBH), bulbous bow volume (BBV), bow flare angle (BFA) and bow entrance angle (BEA). Each parameter had two levels in the variations, thus total 32 cases were designed initially. The results of the numerical simulations were analyzed statistically to determine the main effects and correlations in the five design parameters variations. Among them, the most significant parameter that influences on the added resistance in waves was DWL, followed by BBV and BEA. The other parameters had little effects on the added resistance in waves. By the computations, it was revealed that Extending DWL and decreasing BEA promoted the reflection of waves more toward the side than forward. In addition, there existed two-way interactions for the following two-factor combinations: DWL-BFA, DWL-BEA, DWL-BBV, BBH-BBV.