On the basis of gyrokinetic theory, we derive nonlinear equations for the zonal flow (ZF) generation in intermediate-scale electron temperature gradient (ETG) turbulence (with wavelength much shorter than the ion Larmor radius but much longer than the electron Larmor radius) in nonuniform tokamak plasmas. Both the spontaneous and forced generation of ZFs are kept on the same footing. The resultant Schrdinger equation for the ETG amplitude is characterized by a Navier–Stokes type nonlinearity, which is typically stronger than the Hasegawa–Mima type nonlinearity resulting from the fluid approximation. The physics underlying the three stages of ZF generation process is clarified, and the role of parallel mode structure decoupling is discussed. It is found that ZFs can be more easily excited in the intermediate-scale ETG turbulence than in the short wavelength regime.

在陀螺动力学理论的基础上，我们推导出了中尺度电子温度梯度（ETG）湍流（波长远短于离子拉莫尔半径但远大于电子拉莫尔半径）中纬向流（ZF）生成的非线性方程。不均匀的托卡马克等离子体。ZF 的自发生成和强制生成都保持在同一基础上。ETG 振幅的合成 Schrdinger 方程具有 Navier-Stokes 型非线性特征，其通常强于由流体近似产生的 Hasegawa-Mima 型非线性。阐明了 ZF 生成过程三个阶段的物理原理，并讨论了并行模式结构解耦的作用。