【摘要】 船冰碰撞是船舶碰撞研究领域的热点之一,对冰材料的模拟是船冰碰撞的研究重点。提出一种利用理想弹塑性模型模拟的冰材料本构模型,利用半隐式图形算法计算单元塑性阶段的应力,利用Tsai-Wu屈服准则和经验失效公式用来描述冰的力学行为。利用二次开发功能,将冰材料模型嵌入LS_DYNA程序,并验证该模型的准确性和适用性。研究中针对不同局部形状的冰块与船侧碰撞场景,通过比较分析碰撞力、能量耗散等,探讨冰块的局部形状对碰撞场景的影响。研究结果表明:冰材料模型在大接触面的条件下压力与已有标准吻合较好;在不同的冰块局部形状条件下,船冰碰撞的相互作用过程不同;较钝形状的冰块表现近乎刚体,较尖锐形状的冰块较易破碎。更多还原

【Abstract】 Ship-ice interaction is currently one of the hot topics of the ship collision research, and the modeling of ice material is one of the key issues in ship-ice collision research. A constitutive model of ice material for ship-ice interaction based on the ideal elastic-plastic property is proposed in this paper, which calculate the element stress in plastic stage with the semi-implicit return mapping algorithm and describes the ice mechanical behavior with the Tsai-Wu yield criterion and empirical failure formula. Secondary development function is used to incorporate the ice material model into LS_DYNA program to validate the accuracy and applicability of the model. In accordance with the scenarios of collisions between a ship and ice blocks of different shapes, the study compares and analyzes the collision force, energy dissipation and etc. to discuss the influence of the ice shape on collision scenarios. The result shows that the pressure of the ice material model agrees well with existing standards in case the contact surface is large. The interaction processes of the ship-ice collision are different with different ice shapes. The blunt-shaped ice performs like a rigid body, while sharp-shaped ice is easy to be broken.更多还原