THE RESPONSE OF A PYROTECHNIC POWDER UNDER DYNAMIC LOADING CONDITIONS

Abstract

Experimental and analytical results describing the combustion response of a porous pyrotechnic powder under dynamic loading conditions are described. Pyrotechnic powder samples were subjected to dynamic loading using a piston driven porous bed configuration. Piston impact velocities ranged from about 80 to 300 m/sec. The initial loading density of the porous bed ranged from 54 to 56 percent of theoretical maximum density (TMD). The porous bed of pyrotechnic material ignited and burned at all but the lowest impact velocity tested (81 m/sec) where no reaction was observed. Two impact velocity dependent combustion modes were observed in the high speed motion pictures. No accelerating reactions were observed in either the motion pictures or the pressure gage data for the conditions tested. Traditional analytical porous bed combustion techniques were used in the evaluation of the pyrotechnic response under dynamic loading conditions. The NWCDDT porous bed code was used to model the response of the pyrotechnic power to mechanical stimulus. Calculations of the pyrotechnic powder were complicated by the rebounding of the initial compaction wave off of the end of the confining tube.