Abstract: It is essential for the innovation, transformation and industrial reform of the domestic shipbuilding industry to overcome the design challenges of large Liquefied Natural Gas (LNG) ships and thus solve bottleneck technologies. However, the large LNG ships generally adopt the design of double shafting with double shafting lines of inward inclination angles. This unique design results in an extremely complex flow field at the stern of the ship with increased lateral forces on the shafting, adversely affecting the safe and stable operation of the shafting. The calculation method for the shafting alignment is studied thoroughly by examining the hull deformation, propeller hydrodynamics and bearing oil film thickness of a large LNG double shafting ship. This method more truly reproduces the actual operating state of the shafting, improves the safety margin of the shafting, and obtains a forward-looking, feasible and stable calculation scheme for the dynamic alignment of the double shafting.

Key words: liquefied natural gas (LNG) ship, finite element, shafting alignment, calculation method

摘要： 攻克大型液化天然气（liquefied natural gas,LNG）船舶的设计难题,解决卡脖子技术,是我国造船业创新发展、转型升级和产业改革的必经之路。LNG船通常采用双轴系设计,且双轴线通常具有内偏角度,这种特殊的设计方案令船体尾部流场变得极为复杂,使轴系横向力增大,给其安全稳定运行带来不利影响。该文基于某大型LNG双轴系船舶,从船体变形、螺旋桨水动力、轴承油膜厚度等方面出发,对轴系校中的计算方法开展深入研究。该方法更加真实地还原了船舶轴系的实际运行状态,提高了轴系的安全裕度,得到了具有前瞻性、可行性和稳定性的双轴系动态校中计算方案。

关键词: 液化天然气船, 有限元, 轴系校中, 计算方法