焊接工艺参数对船舶加筋板结构的声振特性影响研究

Influence of welding residual stress on dynamic and acoustic behavior of typical ship structures

[目的]焊接是舰船结构连接的常用方法,焊接对结构的声振特性有一定影响,因此需进一步研究焊接参数对结构声振特性的影响规律。[方法]联合运用热弹塑性有限元法和声固耦合有限元法,探究焊接工艺参数对船舶典型加筋板结构声振特性的影响规律。[结果]结果表明:焊接残余应力受焊接输入功率和焊接速度影响明显,焊接输入功率越高焊接残余应力分布范围越大,焊接速度越慢焊接残余应力分布范围越大。船舶典型加筋板结构声振仿真计及残余应力时,其结构固有频率,加速度响应和辐射声压级频谱曲线等均发生改变。其中固有频率随输入功率增加而下降明显。[结论]仿真模型考虑焊接残余应力将提高结构低阶固有频率和响应预报的准确度,研究可为低噪声焊接工艺制定提供指导。

[Objective]Welding is a common method for connecting ship structures,but it obviously affects their acoustic and vibration characteristics.Thus,it is necessary to study the influence of welding process parameters on the acoustic and vibration characteristics of structures.[Method]In this paper,the thermo-elastoplastic finite element method and acoustic-structure coupling finite element method are combined to study the influence of welding parameters on the acoustic and vibration characteristics of typical ship stiffened plate structures.[Results]The results show that welding residual stress is significantly affected by welding input power and speed.Higher welding input power and lower welding speeds both result in a larger welding residual stress distribution range which causes changes to the natural frequency,vibration response and radiated sound pressure of typical stiffened plate structures.[Conclusion]Welding residual stress should be analyzed to determine the acoustic and vibration response of low-damping welded structures,thereby providing guidance for the formulation of low-noise welding processes.