Combustion of magnesium particles in carbon dioxide under microgravity conditions

Magnesium particles (1-2 mm) are ignited by a hot wire in room-temperature CO2 environment under microgravity and normal gravity conditions. In about 50% of experiments, regardless of the gravity level, a pulsating combustion regime is obtained which may be associated with the relatively low heat re lease in such oxidizer as CO2 and high heat losses. For stable combustion r egime, the burning times measured in microgravity follows a quadratic depen dence with the particle size, which is typical for the diffusion-controlled combustion. Good quantitative agreement with previous data obtained for pa rticles of different sizes indicates that combustion mechanisms of magnesiu m in CO2 are identical in the range of particle sizes 0.05-5 mm.