Effects of the gas puffing neutral on the plasma parameters in the end-cell of GAMMA 10/PDX by using the multi-fluid code “LINDA”

Abstract This research numerically investigates the behavior of plasma flow in GAMMA 10/PDX. The impact of impurity gases seeding into the divertorregion on the plasma parametersand the energy loss processes has been investigated numerically by using the multi-fluid code “LINDA”. The neutral particlesare injected into the bulk hydrogen plasma and the upstream plasma parameterson the z -axis are n i = 1.0 × 10 19 m − 3 , T i = 100 eV , T e = 30 eV . A reduction in the plasma temperature has been observed with the increasing H neutral injection. The ionization and Charge-exchange (CX) power loss increase almost linearly with the increasing H neutral density, which induce a reduction in the plasma temperature. During H seeding, Ar and Ne are seeded simultaneously to observe the influence of Ar and Ne on the electron and ion energy loss mechanism. In this study, the fraction of impurity density to upstream plasma density ( n z / n i ) is used to be 10%. A comparison between Ar and Ne shows that Ar is effective on the electron cooling. The radiation power loss of Ar is found to be higher than that of Ne. The radiation cooling effect and CX loss significantly reduces the electron and ion temperature, respectively. A slight influence of Ar and Ne seeding on the ion energy loss terms has been observed. The electron energy loss terms increase significantly during impurity gas Ar and Ne seeding. These outcomes represent the impact of gas seeding for reducing the plasma energy on the divertortarget plates.