Numerical simulation of ice resistance of ship turning in level ice zone considering fluid effects
【Abstract】[Objectives] When polar ships sailing in polar regions, extremely complex ice resistance poses not only structural threats to ships but new challenges for ship maneuverability, especially when a ship is turning in level ice. In contrast, recent studies have mainly focused on ship–ice interaction with less consideration of effects of fluid on ice loading. [Methods] With the nonlinear finite-element method and based on proper ice material and a reasonable coupling failure mode, this paper studies the complex, strong and nonlinear interaction between ice and ships during turning. In addition, the fluid–structure interaction method is used to consider the influence of fluid on ship–ice interaction. [Results] The validity and reliability of the simulation are determined via the numerical results and empirical formulae. The longitudinal, widthwise and vertical ice resistance to the ship is compared with or without fluid conditions. It is found that ice load has a noticeable increase in three degrees of freedom when the effects of fluid are considered. [Conclusions] Considering the influence of fluid on ice resistance to ship’s ice-breaking movement can effectively ensure the safety of the ship and accurately predict the ice resistance during the turning.
【Keywords】 sea ice; resistance; numerical simulation; fluid–solid coupling; finite element method;
(Translated by HAN R)
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