Inverse evaluation of explosion yield in accident scenarios based on audio-video information fusion

With the continuous increase in the suddenness and frequency of explosion accidents, the rapid acquisition of the explosion yield, as a key parameter for evaluating the explosion power, plays a crucial role in damage assessment and emergency response. Therefore, this paper proposes a method for inverting the explosion yield based on audio and video information of the explosion. By analyzing the time difference between the appearance of firelight and the arrival of the wave, a quantitative assessment of the explosion power is achieved. Based on the Hopkinson-Cranz proportionality law, the Rankine-Hugoniot equation, and the free-field and near-ground overpressure models, the critical proportion distance parameter during the attenuation of the shock wave to the sound wave stage is introduced, and a theoretical model for yield inversion based on the travel time of the two waves is constructed. Through near-ground and air explosion experiments, the wave velocity variation laws under the two conditions are revealed, the validity and applicability of the established model are verified, and the influences of explosion height, frame rate, and frame extraction method on the prediction accuracy of the three models are analyzed. The results show that in the near-ground explosion condition, the ground reflection effect significantly increases the propagation speed of the explosion wave. Compared with the empirical formula based on the travel time of the shock wave and the improved formula combining the travel time of the sound wave, the dual-wave theoretical model proposed in this paper fully considers the differences in the propagation characteristics of the shock wave and the sound wave and the ground reflection effect in near-ground explosions. Under the influence of multiple factors such as explosion height, frame rate, and frame extraction method, it shows better stability and higher prediction accuracy. The audio-video fusion inversion method proposed in this study provides a new technical approach for the rapid assessment of the explosion yield and has broad application prospects in the field of public safety emergency response and protection.