8000M机械合金自蔓延燃烧反应-都柏林三一学院(爱尔兰)

Mechanically-induced combustion reactions were carried out in a transparent quartz vial.
The combustion processes were followed by high-speed video recording and optical
pyrometers. Depending on the vial dynamics, the powder particles were seen to gather in a
periodic collective motion, behaving like a granular gas characterised by subsequent
changes in its density. After ignition, a considerable increase of brightness was observed,
due to the extremely rapid propagation of the high-temperature reaction to the whole mass
of powder. Experimental observations ?nd a very good correlation if compared to the
results of numerical calculations simulating the particle system dynamics. Balls and
powder dynamics were reproduced according to a well-known visco-elastic force scheme,
while chemical conversion of each powder particle was described by a conventional
nucleation-and-growth kinetics. The propagation mechanism of the reaction was studied
and related to the dynamic features of the whole system.