Impact of phase-space turbulence on drift-wave transport in toroidal fusion plasmas

发现了等离子体波对粒子的非线性俘获对等离子体扰动和流动的影响。为此，我们开发了一种新的数学模型，并编制了相应的数值模拟程序。模拟与大型螺旋装置上的实验定性一致，并提出了一种新的不稳定机制，这需要实空间非线性和相空间非线性之间的持续合作。此外，我们还讨论了等离子体湍流动力学模拟中的伪熵产生问题，它与非线性捕获引起的约束问题密切相关。我们展示了这种熵误差如何取决于模拟和物理参数。这些结果总结在四篇论文中，其中一篇提交给物理评论快报，另一篇提交给计算机物理通讯，另外两篇正在准备中。

We identified a new way that nonlinear trapping of particles by plasma wave can affect the perturbations and flows of plasma. To do this, we have developed a new mathematical model, and the corresponding numerical simulation code. The simulations are in qualitative agreement with experiments on the Large Helical Device, and suggest a new mechanism of instability, which requires a sustained collaboration between real-space nonlinearities, and phase-space nonlinearities. In addition, we discussed the problem of spurious entropy production in kinetic simulations of plasma turbulence, which is tied to the filamentation problem due to nonlinear trapping. We showed how this entropy error depends on simulation and physical parameters. These results are summarized in four papers, one of which is submitted to Physical Review Letter, another one is submitted to Computer Physics Communication, and two others are in preparation.