A Study on the Effect of Bow shape on the Added Resistance in Wave

초록

Recently, naval architecture and marine industries started to pay attention to the ship efficiency of fuel consuming and energy saving performance due to the introduction of Energy Efficiency Design Index (EEDI) for reducing gas emission which caused greenhouse effect by International Maritime Organization (IMO). In terms of re-sistance, the effort of decreasing the added resistance in waves has been attempted. In actual sea state, the effect of wind or waves to a ship can increase the resistance of a ship unlikely calm water resistance. In this paper, in order to reduce the motion of a ship, which is major cause in the added resistance of a ship, the flare angle and overhang ratio of a container ship have been changed and the added resistance is analyzed. Moreover, the added resistances of container ship with Ax-bow and Leadge-bow which have good efficiency with decreasing wave reflection in the inci-dent wave condition of short wavelength are compared to the ships with varied flare angle and overhang ratio. First of all, the result of numerical simulation for the object ship is compared with experimental results. The transformations of FO series (a ship with different flare angle and overhang ratio) are only performed in the forward re-gion from station 15 to the longitudinal direction and above the designed waterline to the height direction. After drawing section line using a second-order polynomial curve with the flare angle at the forecastle deck as the boundary condition, the stem profile with the overhang length as the boundary condition is completed. After forming the waterline along the x-direction on each free surface level using the off-sets of the section line and the offsets of the stem profile, the three-dimensional model is completed. In addition, FO concept in bow design has been applied to KCS with Leadge-bow, and the effect of FO concept which can reduce added resistance in both short and long wavelength region is verified. The numerical simulation