基于时频分析技术的爆炸波能量分布及分离

By means of Fourier transform, short time Fourier transform (STFT), continuous wavelet transform (CWT), Wigner-Ville distribution(WVD), an experimental recording signal of blast wave induced by an explosion in near cavity of concrete was analyzed. Then the characteristic of spectrogram of time frequency distribution of explosive wave was obtained and the energy was separated quantitatively. The presented results show that the energy of explosion shock wave distributed in 4-10,13-840KHz and the detonation gas action energy lies in 10-28, 13-175KHz on spectrogram of time frequency distribution. The energy of explosion wave mainly distributed in the frequency bands of 13-840KHz, and it accounted for 74.7% of total energy in 13-234 KHz. Continuous wavelet transform method is the best way to obtain the low and high frequencies information details of explosion and to calculate energy with precision than other time-frequency methods. The shock wave energy of explosion accounted for 24% of total energy in the first 10 and the gaseous expanding energy can accounted for 67.8% in 10-28 by CWD method.