Abstract In this paper, a numerical model based on the non-smooth discrete element method is presented to investigate the effect of ice floe shape on ship resistance under low-concentration broken ice condition where ice fields consist of relatively small and unbreakable floes. The accuracy of the numerical model is validated by the comparison with a series of experiments conducted by the authors with artificial ice floes made from polypropylene (PP) material. The mean ice resistance estimated by the numerical model is in fairly good agreement with both the experimental results and those from the existing semi-empirical formulas. Additionally, the floe shape effect captured in the experiment, i.e. “rectangle-like” floes results in higher resistance than “elliptic-like” floes, is also predicted by the numerical model. Then, the validated numerical model is used to further investigate the effect of floe shape on ship resistance. It has been found that the rectangle floe results in higher ice resistance than other studied floe shapes. The ratio between the maximum and minimum caliper diameters of floe shows little influence on the ice resistance of ship. Finally, the effect of ice thickness on the ice resistance is also discussed.

中文翻译：

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破冰中船舶阻力的数值估算及浮冰几何形状影响的研究

摘要 本文提出了一种基于非光滑离散元法的数值模型，研究了低浓度碎冰条件下浮冰形状对船舶阻力的影响，其中冰场由相对较小且不易破碎的浮冰组成。通过与作者用聚丙烯 (PP) 材料制成的人造浮冰进行的一系列实验进行比较，验证了数值模型的准确性。数值模型估计的平均冰阻力与实验结果和现有半经验公式的结果相当吻合。此外，实验中捕捉到的絮凝物形状效应，即“矩形状”絮凝物比“椭圆形”絮凝物产生更高的阻力，也由数值模型预测。然后，经验证的数值模型用于进一步研究浮冰形状对船舶阻力的影响。已经发现矩形浮冰比其他研究的浮冰形状具有更高的抗冰性。浮冰最大和最小卡尺直径的比值对船舶的抗冰能力影响不大。最后，还讨论了冰厚对冰阻力的影响。