Investigation of In-Flight Alumina Particle Interaction with a Plasma Jet in a Thermal Plasma Reactor

The present study presents the results of an analytical and experimental investigation on the behaviour of Al₂O₃ particles injected into the plasma jet. The dependence of the temperature of the particles and velocity profiles on particle size was estimated by numerically simulating the specific plasma jet in the plasma chemical reactor. The velocity of the particle was investigated experimentally using the ParticleMaster shadowgraphy laser imaging system. The heat flux from the plasma jet to the particles was estimated numerically, and the results were compared with the experimental measurements. Mineral fibre and granules were produced during the plasma spraying process. The studies performed showed that the interaction of the plasma jet and dispersed particles in the reactor mainly depends on the particle’s size, velocity, and temperature of the plasma flow. The modelling and measurements were performed under plasma conditions chosen below the full melting temperature of alumina to avoid particle deposition on the walls while still representative of the reactor environment where finer fractions contribute to melt and fibre formation. The heat flux to the particles inside the reactor increased with the increase in the particle-plasma mass ratio in the reactor.