Development of mathematical hull form of which principal parameters can be varied methodically

Abstract

In this study, the author has developed the mathematical hull form, “generalized Wigley model," based on the modified Wigley model. The proposed hull form presents well the actual ship and it is expressed as explicit function determined by principal particulars of the ship; length L, breadth B, draft d, block coefficient C_b, waterplane area coefficient C_w, and cross-sectional area coefficient amidship C_m. Therefore, the generalized Wigley model is suitable for series calculation when investigating the effects of principal particulars on ship response. To validate the applicability of the proposed form, the author has carried out the calculation of ship motion and vertical vending moment in waves by the actual hull forms as well as generalized Wigley models that have the same ship parameters as the actual ships. As a result, it has been found that the proposed model could imitate actual hull form well regarding enlarged ships. On the other hand, in terms of container vessels, it has been found that the vertical bending moment is over predicted in head sea condition because the proposed form cannot express the large bulbous bow.