Research and Publications

At PPPL, there are three distinct phases of research throughout a graduate career. The first year, we have an experimental project; the second year, we have a theoretical project; finally, in the third year, we begin thesis work.

Thesis Research, 2008-present: Advised by Dr. Greg Hammett and Dr. David Mikkelsen.

Fusion is a promising clean energy source. With a virtually inexhaustible fuel supply of hydrogen isotopes, found in sea water, it could release us from oil dependence. Fusion energy also would not contribute to climate change or have a proliferation risk. One idea for a fusion reactor is a stellarator: a twisted donut-shaped device that uses magnetic fields to contain plasma. To make fusion, we need to keep the plasma very hot and dense for a long enough time. However, turbulence can cool the plasma and break confinement by transporting heat and particles out to the edge near the stellarator walls.

Mathematically, turbulence can be described by gyrokinetics. For my thesis research, I am computationally studying turbulence in stellarator plasmas.

We are improving the gyrokinetic code GS2 to make it more flexible and able to study drift wave stability in a variety of non-axisymmetric magnetic geometries. We've clarified the geometry implementation in the original sequence of grid generating codes. I recently developed a new grid generator to create the geometry input file for GS2. We are benchmarking GS2's linear stability results against three other gyrokinetic codes for a couple of stellarator geometries, and applying GS2 to systematically study the effect of several plasma parameters on linear instabilities in current and under-construction stellarators.

• Simulating Gyrokinetic Microinstabilities in Stellarator Geometry with GS2, Physics of Plasmas 18, 122301 (2011)
• APS DPP 2011
• ICNSP 2011 poster (pdf)
• APS DPP 2010 poster (pdf)
• APS DPP 2010 abstract
• APS DPP 2009 abstract

Practicum, Summer 2008: As a recipient of the U.S. DOE Fusion Energy Sciences fellowship, I spent twelve weeks working with Professor Bill Dorland at the University of Maryland, College Park. I studied in detail and derived the gyrokinetic equation, instabilities, and stellarator geometry and began to use GS2 to study critical gradients in stellarators. Results were presented in a PPPL Graduate Seminar talk during fall semester 2008, and as a poster in the 50th annual APS DPP meeting held November 17-21, 2008, in Dallas, Texas: abstract.

Second-year Project, 2007-2008: In my second year, I worked with Dr. Steve Jardin developing code to solve the 3D, reduced magnetohydrodynamic (MHD) equations in toroidal geometry.

First-year Project, 2006-2007: In my first year, I studied active perturbations in the Magnetic Reconnection Experiment (MRX) current sheet. Results were presented in a PPPL Graduate Seminar talk during fall semester 2007, and as a poster in the 49th annual APS DPP meeting held November 12-16th, 2007, in Orlando, Florida: abstract.