Wave resistance of a ship moving in a lead between rigid ice sheets of finite thickness

Abstract

This paper presents a combined theoretical and numerical analysis of a ship traveling in open water between rigid ice sheets of finite thickness with the objective to understand how the modeled ice influences the wave resistance and ship wave pattern. The first part of the analysis uses a mathematical model to evaluate the wave resistance in deep-water channels (or an ice sheet that reaches the sea floor). The model is able to separate the contributions of the transverse and divergent waves to the total wave resistance. Significant influence of both the ship speed and channel width is observed to both increase and decrease the wave resistance relative to the open water condition by as much as 50%. The second part of the analysis uses high-resolution computational fluid dynamics (CFD) on a contemporary ship that is traveling between two rigid ice sheets with finite thickness. The CFD simulations identify the critical ice thickness that corresponds to the condition in which the ice sheets function nearly as channel walls. It is found that the effect on the wave resistance is noticeable when the ice is 5% of the fundamental wavelength, and when the ice sheets are thicker than 20% of the fundamental wavelength, the resistance change due to the plates is nearly that of channel walls.