Plasma Physics (Physics/ECE/NE 922) Seminars |
Events on Monday, February 17th, 2020
- Understanding, Predicting, and Manipulating Reduced Transport Regimes in Fusion Plasmas
- Time: 12:05 pm - 12:55 pm
- Place: 2241 Chamberlin Hall
- Speaker: David Hatch, Institute for Fusion Studies, University of Texas at Austin
- Abstract: Following a half century of extraordinary progress in plasma magnetic confinement via tokamaks, with, for example, the fusion triple product increasing at a rate surpassing Moore’s law, magnetic confinement finds itself poised on the brink of high fusion gain. The narrow transport barrier that forms at the edge of an H-mode fusion plasma will, perhaps, be the largest determining factor in making the final step to a burning plasma. This transport barrier arises when the conventional plasma turbulence mechanisms are suppressed. This allows a ‘pedestal’—a region of steep pressure gradients—to form, drastically boosting the plasma confinement. ITER, and nearly all other prospective burning plasma devices, are designed to exploit edge transport barriers to achieve their goals.
This talk presents recent breakthroughs in understanding and predicting the ‘residual’ turbulence in transport barriers, which has been difficult to model due to the extreme conditions characteristic of a transport barrier. I will survey the classes of fluctuations that remain in transport barriers; describe how high performance computing is enabling unprecedented physics understanding; discuss how pedestal transport may extrapolate to unfamiliar parameter regimes (e.g., ITER); and describe connections between transport barriers in tokamaks and stellarators. The developing capacity to understand, predict, and manipulate turbulent transport has the potential to enable the realization of optimized configurations that will enable fusion gain on faster time scales and at greatly reduced cost. - Host: Jan Egedal