焊缝对环肋圆柱壳振动声辐射的影响

摘要

This paper studies the effect of welding residual stress on the structure's vibration and acoustic radiation,by choosing the natural frequency as the intermediate quantity. First,the relationship between welding residual stress and natural frequency is analyzed and validated with the experimental method;the result shows that the welding residual stress directly affects the natural frequency. Then,the theoretical derivation about the sensitivity between the natural frequency and acoustic radiated power is conducted, which indicates that the natural frequency serves as an important variable to the acoustic radiated power. In conclusion,the welding residual stress is closely related to the structure's acoustic radiated power and should not be ignored when performing dynamic analysis.%将结构固有频率作为中间变量，研究焊接残余应力、结构固有频率和结构声辐射特性之间的关系。首先，分析焊接残余应力与结构固有频率之间的关系，并通过实验进行验证，结果显示焊接残余应力使结构固有频率发生了显著改变。然后，对固有频率—声辐射功率的灵敏度进行理论推导，并运用有限元法结合边界元法建立数值模型，计算该模型在指定范围内的固有频率—声辐射功率灵敏度，结果证明结构声辐射功率会随着固有频率的变化而发生显著变化。最后，综合分析焊接残余应力与结构声辐射之间的关系。结果表明，研究复杂结构的振动声辐射等动力学特性时，焊接残余应力是不能忽视的影响因素。