Hull form optimization for polar carrier based on navigation state recognition model

Polar Carriers operate in both open water and brash ice areas, where differing navigation environments impose varying requirements on hull form design. Determining the proportion of these navigation areas is crucial for achieving a balanced hull form that optimizes both open water performance and ice-going capabilities. This paper proposes a Navigation State Recognition Model (NSRM) that utilizes GPS data from ship tracks to distinguish between different navigation states, allowing for an assessment of the proportion of open water and brash ice encountered during voyages. Based on the NSRM, a rapid hull form optimization method is developed for polar ships, aiming to minimize total resistance across both open water and brash ice areas. The total resistance is calculated using a weighted sum of the resistances in ice-covered and open-water sections of the route, as determined by the NSRM. The Rankine source and Reynolds-Averaged Navier-Stokes (RANS) methods are employed to calculate open-water resistance, while Juva and Riskas formula is used to estimate ice resistance in brash ice conditions. Additionally, the optimization method is applied to a parent ship with an invisible bulbous bow, resulting in an optimized bow hull form. This demonstrates the applicability of the NSRM-based optimization method for the design of Polar Carrier hull forms.