In the present paper, we revisit observations performed in FT-2 tokamak from previous works. Improvements of core confinement are observed and believed to be caused by wide orbits going from collisionless to collisional regimes. Similar phenomena can occur whenever gradient lengths are comparable to the orbit widths at the top of the pedestal and the loss cone is continuously and increasingly filled by heated particles, collisions and turbulent effects. The lower hybrid heating operator is introduced into the ELMFIRE code to increase the ion temperature during the simulations while keeping the edge temperature low with logical boundary condition at the limiter. Particular focus is given on how the radial electric field deviates from the neoclassical value while introducing turbulent effects.

中文翻译：

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重新审视改进的 FT-2 托卡马克核心约束模拟

在本文中，我们重新审视了以前工作中在 FT-2 托卡马克中进行的观察。观察到核心约束的改进并被认为是由从无碰撞状态到碰撞状态的宽轨道引起的。只要梯度长度与基座顶部的轨道宽度相当，并且损失锥不断地且越来越多地被加热的粒子、碰撞和湍流效应填充，就会发生类似的现象。ELMFIRE 代码中引入了较低的混合加热算子，以在模拟过程中提高离子温度，同时在限制器处使用逻辑边界条件保持边缘温度较低。特别关注径向电场如何在引入湍流效应时偏离新古典值。