水下爆炸船体结构壁压信号时频特征分析

为了研究水下爆炸条件下船体结构壁压信号时频特征,基于某船体结构模型水下爆炸实验壁压数据,利用小波变换良好的时频局部化性质,对壁压信号进行时频特征分析,得到壁压信号在不同频带上的压力时程曲线和能量分布.结果表明,利用小波变换可以方便地获得壁压信号强度、频率和持续时间等时频细节信息.能量统计表明,壁压信号频带分布很广,超过80%的能量主要集中在20kHz以下,5kHz以下频带能量最大.

Analysis of time-frequency characteristics of wall pressure signals of hull structure subjected to underwater explosion

With a view to obtaining the time-frequency characteristics of wall pressure signals of hull structure subjected to underwater explosion, based on the experimental wall pressure data of a hull structure model subjected to underwater explosion, the time-frequency characteristics of the wall pressure signals were studied by means of wavelet transform characterized with good time-frequency localization. By using these wall pressure signals, the pressure-time curves and the energy distributions in different frequency bands were obtained. The experimental results show that it is easy to get the time-frequency information details of the wall pressure signals by the wavelet transform, such as intensity, frequency and duration, etc.. Energy statistics show that frequency bands of the wall pressure signals have a wide distribution, more than 80% of the energy of the wall pressure signals is mainly concentrated in the area of less than 20 kHz and the highest level of energy is below the frequency of 5 kHz.