Numerical Simulations and Theoretical Studies of the Plasma Dynamo and Couette Flow Experiment

该奖项资助进行数值模拟的研究，以支持等离子发电机和库埃特流实验。一个等离子体库埃特实验，首次建立，以研究磁旋转不稳定性（MRI）在一个热，非磁化和快速流动的等离子体。等离子体受到等离子体表面强大的多极磁场的限制。实验的目的是研究高磁雷诺数（适用于天体物理等离子体）下磁共振驱动湍流的核磁共振和可能的磁场自生。如果成功，这个概念可以很容易地扩展到一个更大的，基于等离子体的发电机实验，研究磁场的自生（MHD发电机），但通过流体动力驱动的湍流在一个受限的等离子体。数值模拟和理论研究对于促进对这两个实验的理解和确保它们的最终成功至关重要。利用扩展的MHD代码NIMROD进行数值模拟，并将数值结果与实验测量结果直接进行比较。数值模拟也有望为实验设计提供指导。NIMROD代码的仿真将极大地促进NIMROD代码的验证，NIMROD代码在磁聚变界广泛使用。此外，磁旋转不稳定性（MRI）被认为在许多天体物理环境中起着至关重要的作用。因此，有必要开展一系列物理实验和计算模型，以测试、指导和挑战目前在MRI理论模型中应用的许多规则。该提案已提交给NSF-DoE等离子体科学与工程合作项目联合招标08-589。该奖项由数学和物理科学理事会的物理和天文科学部联合资助。

This award funds research to carry out numerical simulations in support of Plasma Dynamo and Couette Flow experiments. A Plasma Couette experiment, the first of its kind, has been constructed to study Magnetorotational Instability (MRI) in a hot, unmagnetized and fast flowing plasma. Plasma is confined by a strong multipole magnetic field at the plasma surface. The goals of the experiment are to study the MRI and possible self-generation of magnetic field by MRI-driven turbulence at high magnetic Reynolds numbers (the regime applicable to astrophysical plasmas). If successful, the concept could be readily extended to a larger, plasma-based dynamo experiment, studying the self-generation of magnetic field (MHD dynamo) but through hydrodynamic-driven turbulence in a confined plasma. Numerical modeling and theoretical studies are crucial for advancing the understanding of these two experiments and assuring their ultimate success. Numerical simulations using the extended MHD code, NIMROD, will be done and the numerical results will be directly compared with the experimental measurements. Numerical simulations are also expected to provide a guidance for the experimental design.The proposed simulations with NIMROD code would strongly benefit the validation of a code, NIMROD, extensively used by the Magnetic Fusion community. In addition, the Magneto-rotational Instability (MRI) is thought to play a vital role in many astrophysical settings. Thus it is essential to have a line of physical experiments and computational models carried out that can test, guide and perhaps challenge many of the precepts now being applied in theoretical models with regard to MRI. This proposal was submitted to the NSF-DoE Partnership in Plasma Science and Engineering joint solicitation 08-589. This award is being funded jointly by the Divisions of Physics and Astronomical Sciences of the Mathematical and Physical Sciences Directorate.