当前位置: X-MOL 学术Plasma Phys. Control. Fusion › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Nonlocal effects in negative triangularity TCV plasmas
Plasma Physics and Controlled Fusion ( IF 2.2 ) Pub Date : 2021-03-03 , DOI: 10.1088/1361-6587/abe39d
G Merlo 1 , Z Huang 2 , C Marini 3 , S Brunner 4 , S Coda 4 , D Hatch 5 , D Jarema 6 , F Jenko 1, 6 , O Sauter 4 , L Villard 4
Affiliation  

Global gradient driven gyrokinetic simulations performed with the Gyrokinetic Electromagnetic Numerical Experiment (GENE) code are used to investigate Tokamak configuration variable (TCV) plasmas with negative triangularity. Considering limited L-mode plasmas, the numerical results are able to reproduce the actual transport level over a major fraction of the plasma minor radius for a plasma with $\delta_{\textrm{LCFS}} = -0.3$ and its equivalent with standard positive triangularity δ. For the same heat flux, a larger electron temperature gradient is sustained by $\delta\lt0$, in turn resulting in an improved electron energy confinement. In agreement with the experiments, a reduction of the electron density fluctuations is also seen. Local flux-tube simulations are used to gauge the magnitude of nonlocal effects. Surprisingly, very little differences are found between local and global approaches for $\delta\gt0$, while local results yield a strong overestimation of the heat fluxes when $\delta\lt0$. Despite the high sensitivity of the turbulence level with respect to the input parameters, global effects appear to play a crucial role in the negative triangularity plasma and must be retained to reconcile simulations and experiments. Finally, a general stabilizing effect of negative triangularity, reducing fluxes and fluctuations by a factor dependent on the actual profiles, is recovered.



中文翻译:

负三角形TCV等离子体中的非局部效应

使用陀螺动力学电磁数值实验(GENE)代码执行的全局梯度驱动的陀螺动力学模拟,用于研究具有负三角形性的Tokamak配置变量(TCV)等离子体。考虑到有限的L模式等离子体,数值结果能够再现在具有$ \ delta _ {\ textrm {LCFS}} = -0.3 $和等于标准正三角形δ的等离子体的等离子体短半径的主要部分上的实际传输能级。对于相同的热通量,通过$ \ delta \ lt0 $进而导致改善的电子能量约束。与实验一致,也看到了电子密度波动的减小。局部通量管模拟用于评估非局部效应的大小。令人惊讶的是,在的局部和全局方法之间发现的差异很小$ \ delta \ gt0 $,而局部结果对时的热通量有很强的高估$ \ delta \ lt0 $。尽管湍流水平相对于输入参数具有很高的灵敏度,但是全局效应似乎在负三角形等离子体中起着至关重要的作用,必须保持这种平衡以调和模拟和实验。最后,恢复了负三角形的总体稳定效果,将通量和波动减少了取决于实际轮廓的一个因素。

更新日期:2021-03-03
down
wechat
bug