Speaker
Description
It is critical to control the heat load onto the divertor target for the future fusion reactor. While the resonant magnetic perturbation (RMP) is proved to be an effective way to control the transient heat load due to the burst of edge-localized modes (ELMs) [1], the distribution of the inter-ELM divertor heat load will be significantly affected simultaneously [2] due to the three-dimensional (3D) magnetic perturbations. To understand the effect 3D fields on the transport of scrape-off layer (SOL) plasma, the 3D code EMC3-EIRENE [3] based on Monte Carlo method is widely used. On the other hand, pronounced effects on the SOL plasma have been found due to the drifts, which can be well simulated in the 2D code SOLPS-ITER [4] based on the finite volume method. To simulate the SOL plasma with both effects of 3D field and drifts, one possible solution is to develop a 3D code based on finite volume method and find a proper way to introduce the 3D field effect.
In this work, we will report our progress on the development of the 3D SOL plasma transport code based on the finite-volume method. According to the 3D fluid equations of continuity, parallel momentum and ion and electron internal energy, which are derived in a similar way of SOLPS-ITER equations without the restriction of toroidal symmetry, the 3D code is developed using C++ based on the finite volume method. The numerical calculations are performed on the collocated grid, where the convection term is discretized using a hybrid scheme, the diffusion term is discretized using a central difference scheme, and the time differential term is discretized using a first-order fully implicit scheme. The 3D code is preliminarily tested based on an RMP experiment of EAST. The simulation results showed that additional particle flux peaks appeared on the divertor target plate, which reflects the 3D field effect reasonably.
[1] T.E. Evans, et al., Nat. Phys. 2 (2006) 419-423.
[2] J-W. Ahn, et al., Plasma Phys. Control. Fusion 59 (2017) 084002.
[3] Y. Feng, et al., Contrib. Plasma Phys. 44 (2004) 57–69.
[4] X. Bonnin, et al., Plasma Fusion Res. 11 (2016) 1403102.