Thermal Science 2003 Volume 7, Issue 1, Pages: 63-99
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Numerical modeling of disperse material evaporation in axisymmetric thermal plasma reactor
Stefanović Predrag Lj., Cvetinović Dejan B., Živković Goran, Oka Simeon N., Pavlović Pavle B.
A numerical 3D Euler-Lagrangian stochastic-deterministic (LSD) model of two-phase flow laden with solid particles was developed. The model includes the relevant physical effects, namely phase interaction, panicle dispersion by turbulence, lift forces, particle-particle collisions, particle-wall collisions, heat and mass transfer between phases, melting and evaporation of particles, vapour diffusion in the gas flow. It was applied to simulate the processes in thermal plasma reactors, designed for the production of the ceramic powders. Paper presents results of extensive numerical simulation provided (a) to determine critical mechanism of interphase heat and mass transfer in plasma flows, (b) to show relative influence of some plasma reactor parameters on solid precursor evaporation efficiency: 1 - inlet plasma temperature, 2 - inlet plasma velocity, 3 - particle initial diameter, 4 - particle injection angle a, and 5 - reactor wall temperature, (c) to analyze the possibilities for high evaporation efficiency of different starting solid precursors (Si, Al, Ti, and B2O3 powder), and (d) to compare different plasma reactor configurations in conjunction with disperse material evaporation efficiency.
Keywords: two-phase flow, thermal plasma, heat and mass transfer, turbulence, solid particles evaporation, ceramic powders synthesis, numerical modeling