A two-dimensional nodal model with turbulent effects for the synthesis of Si nano-particles by inductively coupled thermal plasmas

Nano-particles synthesis by means of inductively coupled plasma torches is a material process of large technological interest. Numerous parameters concur in the optimization of this process; hence the development of numerical models for the prediction of thermal and magneto fluid dynamics fields, precursor powder trajectories and thermal history as well as nano-particles formation and growth is necessary for the up-scaling of these devices from laboratory batch production to an industrial continuous process. In this work, a 2-D discrete-type model (nodal model) for the analysis of nano-powders nucleation and growth is presented, taking into account convection, diffusion and turbulent effects on particle formation. Discrete-type models feature high precision and reveal much information useful for clarifying the nano-particles formation process. Using Si as precursor material, 2-D simulations of a nano-particle synthesis RF plasma apparatus with a reaction chamber have been carried out. Good agreement has been found comparing results obtained with this model with the ones coming from well-established nucleation-coupled moment method. Moreover, the extended amount of obtainable information that characterizes the nodal model has been underlined.