Analysis of Ar impurity transport in the large tandem mirror device GAMMA 10/PDX plasmas

The purpose of this study is to understand the Ar impurity transport process in the GAMMA 10/PDX. In the present study, the initial simulation using LINDA code and IMPGYRO code has been done to establish the basis of further understanding of the Ar impurity transport. The validity of the simulation model has been discussed by comparisons with those by the theoretical estimations of the friction force and the thermal force. The simulation results show that the Ar impurities with Z = 1 are transported towards the core region, since the thermal force dominates over the friction force under the present calculation conditions. The tendency does not contradict the experimental results and is reasonably explained by the theoretical prediction, i.e., the force balance between the thermal force and the friction force. The robust basis for further model validation and understanding of the Ar transport in the GAMMA 10/PDX has been established.