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 the 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 the 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 the enhancement of the electron temperature in the bulk region and the decrease of the plasma density. The power deposition in the plasma is mainly balanced by the collisional processes and the axial diffusion, whereas it is compensated by the 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 two fluid models show the consistency. The local power balance especially near the wall is improved when the conductive heat is taken into account.

Analysis of Wave Propagation with Different Magnetic Configurations in Helicon Plasmas

“…Once all EM fields have been determined, the power deposition in plasmas can be calculated. The time-averaged power density in plasmas for each m mode is [26,37]…”

“…The influence of background magnetic fields plays a vital role in determining the performance of helicon sources [26]. Traditionally, theoretical and numerical studies have predominantly assumed the applied magnetic fields to be homogeneous, aiming to simplify their inherent complexity.…”