Abstract
Numerical simulation is performed for silicon nanopowder production by means of an argon thermal plasma jet. A simple model is developed to describe a collective growth and convective-diffusive transport of nanopowder. A high-temperature plasma flow which entrains ambient low-temperature gas is simulated successfully; and the spatial distributions and time evolutions of the nanoparticle concentration and mean volume diameter are also clarified. A large number of small nanoparticles are produced especially around the plasma. The regions where the nanopowder has large sizes almost correspond to those where the nanopowder shows low concentrations because the nanopowder grows by coagulation as well as condensation.
