Numerical Solutions to the Grad–Shafranov Equation for Studying Plasma Equilibrium of Alvand Tokamak

Document Type : Research Paper

Authors

1 Assistant Professor, Plasma and nuclear fusion research school, nuclear science and technology research institute (NSTRI), Tehran, Iran.

2 Assistant Professor, Plasma and nuclear fusion research school, nuclear science and technology research institute (NSTRI), Tehran, Iran

Abstract

Alvand tokamak is a small-sized research tokamak for magnetically confined plasma studies. The plasma cross-section of this tokamak is circular, and its simpler structure compared to tokamaks with an elongated cross-section allows for more fundamental physics research. One of the important topics in the stability of tokamak plasma and increasing the confinement time is the study of plasma equilibrium according to the geometry and boundary conditions of the tokamak. In this research, the Grad-Shafranov equilibrium equation for Alvand tokamak geometry was investigated and analyzed numerically. The data obtained from the calculations showed that for a plasma current of about 30 kA and a vertical field coil, a current of 1400 A, the lowest aspect ratio for the plasma cross section is obtained, which will be equal to 4.2. Plasma production with this aspect ratio leads to the presence of plasma in the entire area allowed by the limiters and thus there will be the largest possible volume of plasma in the tokamak chamber.

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