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Simulation study of the influences of beryllium on the tokamak start-up process

Published online by Cambridge University Press:  25 October 2023

Yanli Peng
Affiliation:
School of Science, East China University of Technology, Nanchang 330013, PR China
Yan Qiu
Affiliation:
School of Science, East China University of Technology, Nanchang 330013, PR China
Shiqiu Zhao
Affiliation:
School of Science, East China University of Technology, Nanchang 330013, PR China
Shali Yang*
Affiliation:
College of Science, University of Shanghai for Science and Technology, Shanghai 200093, PR China
*
Email address for correspondence: yangshali@usst.edu.cn

Abstract

Tokamak start-up is strongly dependent on the state of the initial plasma formed during plasma breakdown. To acquire a better understanding of the process and to estimate the influence of the impurity of beryllium on the ohmic heating tokamak start-up process, one-dimensional particle-in-cell coupled with a Monte Carlo collision method has been developed. The main aim is to investigate the plasma performance under various amounts of beryllium with different discharge parameters. Tokamak breakdown with the impurity of beryllium in the ohmic heating strategy has been simulated. The simulation results show that with the impurity of beryllium, the increase of plasma density is suppressed compared with the case without beryllium. The breakdown time is delayed by the impurity. Moreover, the successful breakdown has a much higher requirement on discharge parameters with a low electric field operational scenario, since in the low electric field discharge the influence of beryllium impurity is greater. As the plasma density increases, the effect of beryllium impurity on plasma becomes more critical. It indicates that impurities cannot be neglected in the high plasma density.

Type
Research Article
Copyright
Copyright © The Author(s), 2023. Published by Cambridge University Press

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