大型LNG船双轴系非平行布置设计

Twin Shafting Non-Parallel Design Applied on Large Scale LNG Carriers

从LNG贸易市场发展角度出发,节能型LNG船是未来发展的主要方向,采用双轴系非平行布置设计能够有效提高大型LNG船的推进系统效率。通过水动力CFD模拟计算分析双轴系非平行布置的技术特点发现,双轴系非平行布置设计能够使螺旋桨进水更加充分,还可以有效降低船舶尾部结构受到的水流冲击力,具有节能提效的潜能。重点研究该设计在实船应用中遇到的特殊齿轮箱基座结构设计、起吊设施的倾斜布置、机舱底层设备紧凑化布置、全悬挂舵的匹配安装等技术挑战,分析问题并提出相应的解决方案。通过实船试航的验证试验,一方面证明非平行布置双轴系推进系统的可靠性,另一方面也确认了双轴系非平行布置设计达到预想的节能指标。

It is believed that the energy saving type LNG carriers will be more popular in future considering the latest development of LNG trade market.And the twin shafting non parallel design is proposed to improve the efficiency of ship propulsion system.The technical characteristics of the twin shafting non parallel design is analyzed by the hydrodynamic CFD simulation calculation,and it is found that the twin shafting non parallel design can increase the propeller water inlet and reduce the force working on ship's bottom structure.That means there is some potential to save energy and improve efficiency of the propulsion system.The technical challenges caused by the design application are focused on,such as the special gearbox foundation design,the inclined arrangement of the lifting facilities,the compact equipment arrangement on tank bottom level of engine room,the installation of the full spade rudder,etc.The possible technical problems are expatiated and the typical solutions are proposed.The twin shafting non parallel design is verified by sea trail.On one hand,the reliability of the propulsion system is proved,and on the other hand,the improvement of energy saving is confirmed.