Modelling and simulation of DC Arc plasma involving arc fluctuation and non-equilibrium mixing effects
About this project
The application of near atmospheric thermal plasma in chemical processing can be characterised by the use of the arc column or the tail flame. While the use of hot tail flame has led to the proliferation of plasma-based waste destruction processes, the plasma-activated chemical synthesis requiring high activation energy is primarily dependent on reaction within the arc column. A few examples includes plasma assisted cyanide and acetylene production. The plasma-chemical process is distinguishable from conventional thermal chemical reactions in 2 ways: (i) smashing the reactants under the high energy to generate ionic species, and (ii) quenching the species under specified conditions to provide thermodynamic conditions of interest for making desired product. To achieve effective molecular activation, a good mixing of reactant species within the plasma is desirable. However the anomalous behaviour of gas viscosities and densities, at temperature > 5000 oC, hinders molecular mixing and results in formation of non-equilibrium zone in the reactor. It is therefore imperative to understand the transport pattern of the ionic species, primarily under the non-equilibrium conditions to optimise a plasma reactor. Visualization of the arc inside the plasma torch is challenging even using the most advanced imaging technology.
Fortunately, advances in computational capability can help bridge the knowledge gap. The modelling of arc discharge in thermal plasma requires the combination of mutually related fluid-dynamics and electromagnetic phenomenon. Where the conventional models based on local thermodynamic equilibrium(LTE) assumptions fails to provide a real description of plasma formation, the proposed research will dwell into the NLTE modelling to capture the true mixing behaviour of reactive species in the plasma reactor. The modelling approach will also involve coupling a set of chemical kinetic together with plasma dynamics model to specifically investigate the slow reaction dynamics near the cold boundary walls.
Develop and deliver a NLTE model of a plasma system to simulate the plasma flow dynamics using CFD codes.
Determine the optimal dosing method of cold reactant gas into the plasma devise to enhance mixing between reactants and plasma species.
Experimental validation of model outcome on laboratory scale plasma devise.
Coupling of reaction kinetics with the plasma species transport model to develop a comprehensive model package.
Application of chemical-plasma model to determine the efficiency of hydrogen production via plasma hydrocarbon and plasma waste pyrolysis.
Information for applicants
CFD modelling skills, Competent in solving stiff partial differential equations, Strong foundation in heat transfer and fluid flow dynamics.
Knowledge of Electromagnetic phenomenon, Skill in thermal plasma plume modelling,
Expected qualifications (Course/Degrees etc.)
Chemical Engineering, Mechanical Engineering, Mathematics, Physics,