AI 中文总结
研究平衡态\(\vec{E}\times \vec{B}\)流剪切对等离子体湍流的影响，通过陀螺动力学模拟等方法，发现施加剪切会破坏自生带状流致输运上升，简化模型揭示原因，且球形托卡马克放电模拟表明环形旋转受热量注入限制。
AI 中文摘要
平衡态剪切\(\vec{E}\times \vec{B}\)流这一标准的等离子体湍流解决方案可能会适得其反。在新确定的一种状态的陀螺动力学模拟中，施加的剪切与固有带状剪切相当，会破坏调节湍流的自生带状流：在更强的剪切抑制它之前，输运会急剧上升。一个简化的流体模型将此归因于施加的剪切层和带状剪切层的不相容性。球形托卡马克放电模拟表明，推断出的旋转剪切处于急剧输运增加的阈值或略低于该阈值，这意味着环形旋转可能主要受热量而非动量注入的限制。
英文摘要
A novel physical mechanism whereby sheared equilibrium flow enables temperature-gradient-driven turbulence is identified. Gyrokinetic simulations of ion-scale plasma turbulence show that imposed equilibrium $\vec{E}\times \vec{B}$ flow shear can destroy the self-generated zonal flows that regulate the turbulence. This results in transport that increases sharply with flow shear. A reduced fluid model demonstrates that this is due to the spatial incompatibility of imposed and zonal shear layers. Simulations of spherical tokamak discharges place the inferred rotation shear at, or just below, the threshold of the sharp transport increase, implying that the toroidal rotation can be determined primarily by heat, rather than momentum, injection.
