破冰船在层冰中运动的数值模拟方法

为研究破冰船在层冰中运动的特点与海冰的破坏方式，该文建立了包含冰载荷、敞水阻力、螺旋桨推力与舵力的六自由度动力学方程。考虑海冰的弹性弯曲对破冰力的影响，引入海冰的二次断裂与动态弯曲破坏准则，提出了更加精确、完善的船-冰动态接触模型。在此基础上，对瑞典破冰船Tor Viking Ⅱ在层冰中的直航与回转运动进行了数值模拟，并与全尺寸试验数据对比，验证了数值模拟结果的合理性。结果表明:模拟运动轨迹与真实运动轨迹相符，最大回转直径的相对误差仅为3.32%，因此本文建立的数值模拟方法能够真实地模拟破冰船在层冰中的运动。

NUMERICAL SIMULATION METHOD FOR MOTIONS OF THE ICEBREAKER IN LEVEL ICE

To study the motion characteristics of the icebreaker in level ice and the failure mode of sea ice,a six-degrees-of-freedom kinetic equation is established including ice loads,open water resistance,propeller thrust and rudder forces.Considering the influence of the elastic bending of sea ice on icebreaking force,the secondary fracture and the dynamic bending failure criterion of sea ice are introduced,so that a more accurate and perfect ship-ice dynamic contact model is proposed.Based on these theories,the direct sailing and the turning motions of the Swedish icebreaker,Tor Viking II,are simulated in level ice.The numerical simulation results are compared with full-scale trial data to verify its rationality.The results indicate that the simulated trajectory is consistent with the real trajectory.The relative error of the maximum turning diameter is only 3.32%.Therefore,the numerical simulation method established in this paper is able to authentically simulate the motions of the icebreaker in level ice.