Explosion air shock wave waveform testing device and method based on spring dynamic response
Xiaoci Zhao, Jingjing Song, Minzu Liang, Zizhen Qi, Jiaqiang Wu, Yuliang Lin, Yuwu Zhang, Rong ChenElectrical measurement and equivalent methods, the two main techniques for testing explosion air shock waves, suffer, respectively, from electromagnetic interference and an inability to record waveform evolution over time. Here, we describe a spring-dynamic-response apparatus designed to circumvent these problems. The device uses an array of spring-loaded pins with graded stiffness to sample discrete points on the shock wave curve. From the measured displacements of these pins, the peak overpressure and the positive pressure duration are determined. We calibrated the sensitivity coefficients of the device through light-gas-gun impact experiments and validated the method by conducting spherical-charge trinitrotoluene explosion tests. A data processing scheme based on impulse conservation is also developed. Our experimental results demonstrate that the apparatus successfully reconstructs shock wave waveforms, with errors in peak overpressure and positive pressure duration falling within 18.0% and 10.4%, respectively. In addition, by introducing a compensation coefficient σ derived from specific test conditions to compensate for system losses caused by friction and other factors, the overall error can be reduced to ∼3.5%. This work provides a practical alternative for shock wave testing in harsh environments and extends the engineering applicability of waveform measurement techniques.