In this work a coupled model for the production of nanoparticles in an inductively coupled plasma reactor is proposed. A Lagrangian approach is used to describe the evaporation of precursor particles and an Eulerian model accounting for particle nucleation, condensation, and fractal aggregation. The models of the precursor and nanoparticles are coupled with the magneto-hydrodynamic equations describing the plasma. The purpose of this study is to develop a model for the synthesis of particles in a thermal plasma reactor, which can be used to optimize industrial reactors. The growth of aggregates is considered by introducing a power law exponent D f . Results are compared qualitatively and quantitatively with existing experimental data from plasma reactors at a relatively large laboratory scale. The results obtained from the model confirm the previously observed importance of the quench strategy in defining the morphology of the nanoparticles.

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A numerical model for an air inductively coupled plasma (ICP) torch with a supersonic nozzle is developed using reaction rates under chemical non-equilibrium. The reaction model takes into account 11 species (neutral species: N2, O2, NO, O, N and charged species: , , NO+, O+, N+, e−) in air ICP. The species distribution in the air inductively coupled thermal plasma with a supersonic nozzle is obtained by solving the mass conservation equations taking into account diffusion, convection and chemical reactions. The thermal conductivity, electrical conductivity, viscosity and diffusion coefficient are calculated at every step of the computational process using the method of Chapman and Enskog. The most recent sets of collisions integrals available in the literature are used, taking into account higher-order formulae to compute the electron transport properties.In this work, the deviation from chemical equilibrium (CE) is determined by comparing with the CE calculation result and is found to be very important. The influence of different order formulae to calculate the electron transport properties (electrical conductivity) on electromagnetic fields is also investigated and recommendations can be made according to the range of temperatures, powers and flow rates expected in the plasma torches.

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In this work, a non-equilibrium mathematical model for an air inductively coupled plasma torch with a supersonic nozzle is developed without making thermal and chemical equilibrium assumptions. Reaction rate equations are written, and two coupled energy equations are used, one for the calculation of the translational–rotational temperature Thr and one for the calculation of the electro-vibrational temperature Tev. The viscous dissipation is taken into account in the translational–rotational energy equation.The electro-vibrational energy equation also includes the pressure work of the electrons, the Ohmic heating power and the exchange due to elastic collision.Higher order approximations of the Chapman–Enskog method are used to obtain better accuracy for transport properties, taking advantage of the most recent sets of collisions integrals available in the literature. The results obtained are compared with those obtained using a chemical equilibrium model and a one-temperature chemical non-equilibrium model. The influence of the power and the pressure chamber on the chemical and thermal non-equilibrium is investigated.