Investigation of radial heat conduction with 1D self-consistent model in helicon plasmas

Abstract

A 1D radially self-consistent model in helicon plasmas has been established to investigate the influence of radial heat conduction on plasma transport and wave propagation. Two kinds of 1D radial fluid models, with and without considering heat conduction, have been developed to couple the 1D plasma–wave interaction model, and self-consistent solutions have been obtained. It is concluded that in the low magnetic field range the radial heat conduction plays a moderate role in the transport of helicon plasmas and the importance depends on the application of the helicon source. It influences the local energy balance leading to enhancement of the electron temperature in the bulk region and a decrease in plasma density. The power deposition in the plasma is mainly balanced by collisional processes and axial diffusion, whereas it is compensated by heat conduction in the bulk region and consumed near the boundary. The role of radial heat conduction in the large magnetic field regime becomes negligible and the two fluid models show consistency. The local power balance, especially near the wall, is improved when conductive heat is taken into account.