抄録
This paper investigates the applicability of direct simulation considering a stratified atmosphere to an unsteady analysis of a blast wave caused by a meteorite explosion. Axi-symmetric Euler equations with a gravity term that considers a horizontally stratified atmosphere are numerically solved to analyze blast wave propagation from the source of meteorite explosion to the ground. Computations are made to reproduce the blast wave generated by the Chelyabinsk meteorite in 2013, assuming a spherically uniform high-pressure and high-temperature core as the source of explosion. The amount of energy released by the explosion at an altitude of 25 km is assumed to be 500 kt of trinitrotoluene, and the computational domain ranges over a radial distance of 50 km from the center of the explosion. The simulation results in a uniform atmosphere agree well with the results of well-known Brode’s empirical formula, and the blast wave obtained from the simulation considering a standard atmosphere is expected to cause serious damage to the ground, as experienced at the time of the Chelyabinsk event. Moreover, the simulation results clarify the characteristics of blast wave propagation through uniform, isothermal, and standard atmospheres.
