Study of end-cell plasma parameters of GAMMA 10/PDX by the LINDA code

Abstract

This research numerically investigates the plasma behavior during neutral gases puffing into the west end-cell of the linear plasma confinement device GAMMA 10/PDX. A multi-fluid code named ‘LINDA’ is developed and applied at the west end-cell of the device to explore the processes of plasma detachment and energy loss mechanism during plasma-neutral interactions. The ion heat flux limiter is newly introduced in the LINDA code. In the paper, we investigate the influence of the ion heat flux limiter in our divertor plasma models to understand how the ion heat flux limiter affects the computed plasma parameters. The upstream plasma parameters are The effect of ion heat flux limiting reduces the ion temperature and heat flux in the direction of the target plate. The ion temperature profile is shown to be similar when the heat flux limiting factor (αi) is varied from 0.2 to 2.0. The effect of Hydrogen (H) and Argon (Ar) gas puffing has been investigated under the condition of ion heat flux limiting factors αi = 1.0. The ion temperature is shown to be similar between Ar and without Ar puffing. On the other hand, Te reduces remarkably for Ar puffing by enhancing the radiation cooling of Ar. The ion and electron loss are greatly enhanced for combined puffing of Ar and H. The ionization loss is found to be slightly higher and the charge-exchange loss is found to be slightly lower during the ion heat flux limiting case. These outcomes may contribute to understanding the plasma detachment processes in fusion devices.