29000t散货船上层建筑振动特性预报

Prediction of Vibration Characteristics of Bulk Carrier Superstructure

近年来,各类货船机舱布置在尾部,高耸而单薄的上层建筑就在机舱之上,螺旋桨脉动压力、主机干扰力激起的上层建筑剧烈振动的事故时有发生。为了在设计阶段对上层建筑振动特性进行控制,本文应用上层建筑加船体梁的简化模型分析了29000t散装货船上层建筑的振动,在设计阶段预报了该船上层建筑的振动特性,为改进设计提供了依据。计算结果得到DNV的认可。与整船体离散模型(节点10000以上,单元40000之多)相比,该模型节点单元少(1000左右),费用省,适应我国现有的计算机条件。该分析方法具有实用意义。

The engine room of a bulk carrier is usually arranged at the stern with high and thin superstructure on it. Violent superstructure vibration may occur, caused by the propeller and the engine. In order to prevent such a harmful condition, the authors presont a simplified model (Superstructure+ girder) for the prediction of vibration characteristics of a 29000 DWT bulk cargo carrier superstructure at early design stage. Compared with the whole hull discreted model, the simplified model uses fewer nodals and elements. So this approach is efficient, practical and suitable for moderate sized computer. This simplified model enables the designer to modify the original scheme if necessary.