浮态对船舶操纵性的影响研究

Research on the Effects of Floatation Condition on Ship Manoeuvrability

针对装货、卸货、压载水等导致的船舶浮态变化对其操纵性影响的问题,以超大型原油轮KVLCC2为对象,首先采用基于开源CFD软件Open FOAM二次开发的RANS求解器,计算KVLCC2在6个浮态(考虑2个吃水和3个纵倾角)下的斜航与圆周耦合运动水动力,分析浮态对操纵水动力的影响,然后运用回归水动力得到的水动力导数,采用MMG模型仿真各浮态的KVLCC2回转运动和Z形运动,分析浮态对纵距、横距和超越角等特征参数的影响。将部分水动力计算结果和回转、Z形运动仿真结果与试验数据进行比较,吻合良好,验证了研究方法的正确性。

To investigate the influence of varies of floatation conditions,which is caused by load,unload and ballast water,on ship manoeuvrability,a super large oil tank KVLCC2 is employed.At the first,a RANS solver,which is secondary developed based on an open source CFD software named OpenFOAM,is adopted to compute the hydrodynamic forces under six floatation conditions(2 drafts,3 trims)of KVLCC2 in the oblique and circular coupled motion,and the effect of the floatation condition on the hydrodynamic forces is analysed.Then,the hydrodynamic derivatives,which is regressed from the hydrodynamic forces,is used to simulate the turning and zigzag motion of KVLCC2 in each floatation condition by a MMG-type model.The effect of floatation condition on the characteristic parameters(such as advance,tactical diameter and overshoot angle,etc)is analysed.Some computed results of hydrodynamic forces and simulated results of turning and zigzag motion are compared with the experimental data.The results show that the computed results and the simulated results of turning and zigzag motion are in good agreement with the experimental data,which verifies the correctness of the research method adopted in this paper.