板壳结构在声振联合试验下的振动响应耦合分析

Analysis of Response Coupling of Plate Shell Structure under Vibro-acoustic Test

目的研究具有工程实践意义的板壳组合结构在声振联合作用下的响应预测方法。方法在噪声试验、振动试验和声振联合试验响应曲线的基础上,分析板壳组合结构在噪声和振动同时激励下的响应耦合规律,并根据噪声试验和振动试验的响应极值包络法,来预测在声振联合试验作用下板壳结构的响应分布。结果声振联合试验响应曲线近似于噪声试验和振动试验的最大值包络线,噪声的面激励和随机振动的基础激励在不同的频率范围内对结构响应起着主要影响。试验件的噪声试验和振动试验响应曲线在给定的频率点出现相交,小于交越频率的声振联合试验响应与振动试验高度吻合,高于交越频率的响应则以噪声试验为主。结论在工程实际中,可以直接利用振动试验和噪声试验的响应数据对声振联合试验的响应进行预测。由于交越频率难以事先获得,因此响应叠加法在实践中更易于实现。

The work aims to propose an engineering method with practical significance to predict the response of plate shell structure under vibro-acoustic coupling.Based on the response curves of noise test,vibration test and vibro-acoustic test,the response coupling law of plate shell structure under simultaneous excitation of noise and vibration was analyzed,and the response distribution of plate shell structure under vibro-acoustic test was predicted according to the response extremum envelope method of noise test and vibration test.The response curve of vibro-acoustic test was approximately the maximum envelope line of the noise test and vibration test.The surface excitation of noise and the basic excitation of random vibration mainly impacted the structural response in different frequency ranges.Response curves of noise test and vibration test intersected at the given frequency point.The response of vibro-acoustic test below the crossing frequency was highly consistent with the result of vibration test,while the response above the crossing frequency was mainly similar to the noise test.Based on these results,the extremum envelope method can be used to predict the response of plate shell structure under vibro-acoustic test by the response data of noise test and vibration test in engineering practices.In addition,the response superposition method is more suitable because it is difficult to obtain the crossing frequency in advance.