The correlation theory of turbulence suppression (Zhang and Mahajan 1993 Phys. Fluids B5 2000) by velocity shear was constructed by invoking the ansatz of potential vorticity conservation (PVC) that holds for relatively simple (slab) models of drift wave turbulence. It is, therefore, surprising that a detailed modern simulation of the H mode pedestal, using the gyrokinetic code GENE (Hatch et al 2018 Plasma Phys. Control. Fusion 60 084003), found ‘striking agreement’ with the predictions of the analytic model. To understand the reasons for this remarkable agreement, an extended theory that contains finite (magnetic) curvature, and which does not conserve potential vorticity, is developed and ‘solved’ by calculating an inhomogeneous Green function reflecting the fact that the new system has a potential vorticity source. It is, then, demonstrated that the effect of the broken PVC is insignificant for the normal operation parameters in tokamaks; the correction due to curvature is at the order of , where is the scale length of the local gradient and is the major radius. The excellent agreement between simulation and slab model 1993 theory is therefore not accidental; the latter can be applied with confidence to the tokamak pedestal.

通过调用电位涡度守恒（PVC）的ansatz来构造通过速度剪切抑制湍流的相关理论（Zhang and Mahajan 1993 Phys。Fluids B5 2000），该理论适用于相对简单的（平板）漂移波湍流模型。因此，令人惊讶的是，使用陀螺动力学代码GENE对H模式基座进行了详细的现代仿真（Hatch等人2018 Plasma Phys.Control.Fusion 60084003），发现分析模型的预测具有“显着性”。为了理解达成这一惊人协议的原因，通过计算反映新系统具有潜力的事实的不均匀格林函数，开发并“解决了”包含有限（磁）曲率且不保留潜在涡度的扩展理论。涡度源。因此，证明了破碎的PVC的影响对于托卡马克中的正常操作参数而言是微不足道的。由于曲率引起的校正约为，其中是局部梯度的标度长度和是主要半径。因此，模拟与平板模型1993理论之间的出色一致性并不是偶然的；它不是偶然的。后者可以放心地应用于托卡马克底座。