Critical temperature for nanoparticle cloud formation during combustion of single micron-sized iron particle

Temporally, spatially, and thermally resolved measurements of in situ nanoparticle cloud formation during combustion of single micron-sized iron particles are carried out. The critical particle temperature for the cloud formation is identified using high-speed and high-magnification shadowgraphy, recording the evolution of a nanoparticle cloud, synchronized with two-color pyrometry probing the surface temperature of the burning micron particle. The finding could serve as an important criterion to minimize nanoparticle generation in the flame of iron-particle suspensions, making iron powders a cleaner and more recyclable fuel