船舶下行过弯船位摆置方法数值计算

Calculation method for positioning a ship preparing to go down stream through a curved channel

随着船舶大型化发展,越来越多的海船进出内河航道,然而我国内河弯曲航道宽度有限,加上受弯曲航道扫弯水的影响,大型船舶在内河弯曲航道航行潜在一定风险。船位摆置决定了航行于航道中的船舶能否顺利过弯,在长期航行实践中,主要采用“挂高取矮”这一经典过弯航法。目前,国内外对船舶过弯时船位摆置的量化研究较少,驾引人员大多只凭借经验,并不能根据实际水流条件,准确判断船舶过弯时应摆置的船位。因此,基于“挂高取矮”航法,建立船舶过弯船位摆置数学模型,通过Matlab分别对过弯船舶横移量和航迹带宽度与偏航角和横流的关系进行数值计算,量化研究船舶船位摆置方法。结合尹公洲弯曲航道,利用船舶操纵模拟器进行仿真模拟,仿真结果与数值计算结果基本一致,表明数值计算结论可信,且具有一定工程应用价值。

A ship,especially a larger one,has to take an appropriate start position in a river to smoothly travel through a river bend.That start position has been chosen according to experience gained in long navigation practice.A pithy formular"taking higher side and aiming for lower side"has been the general guidance.This paper quantitatively analyzes the process of ship travelling through a river bend and develops a method to calculate the position where a ship starts to sail through a river bend according to actual water flow in the river.A positioning model is built based on ship motion process and the ship lateral displacement and track width are calculated against the yaw angle and transverse flow by means of Matlab.The position the ship should take before starting to travel through a river bend is decided based on the calculation results.The calculation for Yingongzhou curved waterway is checked through simulation and proved.