Design and Analysis of a Plasma Chamber for Thermal Processing Applications

Thermal Plasma processing has many applications in medical and environmental fields like melting, smelting and waste disposal. Here, the primary vessel known as plasma chamber is preheated to a high temperature of around ∼1000◦C using plasma arcs. In this design process, CFD (Computational Fluid Dynamics) analysis has played a major role in defining the design of the plasma chamber. The simulation methodology has been benchmarked based on comparison of experiment and CFD simulation carried out for an experimental system available at IPR (Institute for Plasma Research). Transient thermal profile of the chamber has been evaluated using CFD analysis to design a higher capacity plasma chamber for scaled up systems. The analysis helped in identifying the desired material properties, dimensions of chamber and thickness of insulation, refractory materials to be used for the construction of chamber. The design focusses on uniformity of temperatures inside the chamber, identification of hotspot locations and faster ramp up time to desired process temperatures. Temperature at the outer most surface of plasma chamber have also been evaluated using the CFD analysis for human safety. The CFD analysis is computationally expensive and time consuming due to large size, transient behaviour and inclusion of radiation transport.