分析模型选取对螺旋桨脉动激励引起水下结构振动与声辐射影响研究

Effect of analysis model selection on underwater structure vibration and acoustic radiation caused by propeller disturbing force

由于激振力作用位置的原因,目前关于水下结构振动与辐射噪声特性问题的分析模型多选用舱段或尾部结构,本文用有限元/直接边界元方法,分析螺旋桨—轴系—壳体结构这一典型的尾部受迫振动问题,研究不同模型选取对结构振动及声辐射特性的影响,分析表明,用局部模型将对结构的振动特性、辐射声压分布等特性产生影响,分析结果中略掉了较多结构振动模态,导致分析结果不全面,对于水下结构的振动响应分析,建议采用整体结构作为分析模型。

Because of the action location of disturbing force, the cabin and stern models were often chosen as an analysis model for underwater structure vibration and acoustic radiation. Here, the finite element analysis and the direct boundary element analysis were adopted, the propeller, shafting and shell structure were coupled together as a typical model, the effect of different analysis model selection on underwater structure vibration and acoustic radiation was calculated. The results showed that the stern model has large effects on structure vibration features and underwater sound pressure distribution; but, some structural vibration modes are ignored, this leads to an imperfect analysis; in order to analyze the underwater structure vibration responses perfectly, the model of the whole underwater structure must be adopted.