Shock wave dynamics and venting overpressure hazards induced by indoor premixed hydrogen/air explosion

To further investigate the venting shock wave dynamics and overpressure hazards induced by indoor hydrogen/air explosion, an explosion-venting model of 6 m × 3 m × 2.5 m with a vent was established by computational fluid dynamics (CFD) technology. The results show that the combustion rate structure of venting flame composed of three peaks completely reflects the evolution of the venting flow field, and the significance and arrival time of the peak R₃ reflect the severity and hysteresis of the external explosion; The propagation of the external explosion wave in two directions, away from and near the vent, resulting in the evolution of the traditional two-wave and three-area structure into a three-wave and four-area structure. The new wave structure contains the reverse cancellation of the external explosion wave and explosion-venting wave, and the co-direction superposition with the precursor wave, in which the wave-wave superposition forms a new significant peak P_s-max; The distribution characteristics of venting overpressure hazard under the external explosion and wave-wave superposition become unpredictable. The severe damage zone to building will evolve repeatedly on the explosion-venting path, and the dead zone may appear far away from the vent. The research results provide a scientific basis for the prevention and mitigation of explosion disasters in hydrogen-related industrial plants.