Study on the factors influencing the interaction and coalescence of shock waves from multiple explosion sources in free field

The interaction and coalescence of shock waves originating from multiple explosion sources were studied using numerical simulations and theoretical analysis. The effects of the mass distribution, layout, and quantity of explosion sources were considered, and an engineering calculation model for shock wave parameters at the focus center was established. The results show that the peak overpressure at the focus center is significantly changed only when the mass ratio of the two explosion sources increases beyond two. Overall, the peak overpressure at the focus center decreases with the increase in mass ratio. The focus effect of multiple explosion sources is the greatest when the sources are uniformly distributed on a circle. When the number of explosion sources is less than four, the peak overpressure and specific impulse at the focus center increase with the increase of the number of explosion sources. Increasing the number of explosion sources from one to four results in an increase in the peak overpressure by a factor of 0.73–5.23 and an increase in the specific impulse gain by a factor of 1.59–4.71. The results from simulations and experiments verify the validity of the model used to characterize multiple explosion sources.