Description
Abstract
The edge radial electric field (EREF) plays an important role in the L-H transition, and the ion orbit loss is thought crucial in the generation of the EREF in the tokamak plasma [1,2]. The gyrokinetic (GK) simulation is useful for investigating the ion orbit loss effect [2,3], so we extend the function of the nonlinear GK global code NLT [4] to simulate the edge plasma with limiter configuration, and perform some benchmark tests with the analytical results [1]. We also implement the ion-orbit-flux diagnostic module [2] in the NLT code to quantitatively measure the ion orbit loss effect. In our simulation, the EREF is generated by the ion orbit loss of the initial Maxwellian distribution with uniform radial profile. The width of the EREF pedestal is about the banana width compressed by the EREF, and the magnitude of the edge electrostatic potential is roughly proportional to the edge ion temperature. The ion orbit loss is almost reduced to a negligible level with the established EREF. These simulation results are consistent with the analytical and experimental results [1,5].
References
[1] X. Xiao, L. Liu, X. Zhang, and S. Wang, Phys. Plasmas 18, 032504 (2011)
[2] H. Zhu, T. Stoltzfus-Dueck, R. Hager, S. Ku, and C. S. Chang, Nucl. Fusion 62, 066012 (2022)
[3] M. A. Dorf, M. R. Dorr, J. A. Hittinger, R. H. Cohen, and T. D. Rognlien, Phys. Plasmas 23, 056102 (2016)
[4] L. Ye, Y. Xu, X. Xiao, Z. Dai, and S. Wang, J. Comput. Phys. 316, 180-192 (2016)
[5] E. J. Doyle et al, Plasma Physics and Controlled Nuclear Fusion Research 1992 (IAEA, Vienna, 1993), Vol. 1, pp. 235-247