Newswise — Vincent Graber, a doctoral student in mechanical engineering at Lehigh University, has won a highly competitive award from the U.S Department of Energy (DOE) that he will use to conduct research at the DOE’s Princeton Plasma Physics Laboratory (PPPL) on the design of a critical device to help bring the fusion energy that powers the sun and stars to Earth. The award, one of 62 recently announced by DOE under the Office of Science Graduate Student Research (SCGSR) Program, enables standout graduate students in science and engineering to pursue part of their doctoral theses  in collaboration with a researcher at a DOE national laboratory.

Control burning plasmas

Graber will work with PPPL physicist Dan Boyer during the six-month award, whose start has been delayed until he can be physically present at the Laboratory. His research will explore techniques to control burning plasmas — largely self-heating fusion reactions that the international fusion experiment ITER is being built in France to demonstrate. “This will be a great learning and training opportunity for me,” said Graber, who received his Bachelor of Science degree from Lehigh in 2017 and is entering his fourth year of graduate school. “This project will be invaluable for my doctoral thesis research.”

Boyer, who earned his Ph.D. from Lehigh under Professor Eugenio Schuster, who now advises Graber, will help the graduate student carry out his plans. “Vincent is looking forward to the new control challenges we will face during burning plasma operations on ITER,” Boyer said. “He has developed sophisticated methods for handling the complexity of the problem, and has demonstrated their performance on reduced models. Since we cannot test his proposed approaches experimentally until several years into ITER operations,” he adds, “the critical next step is to use high-fidelity simulations to test and refine these approaches.”

Graber also will work with PPPL physicist Francesca Poli, who is developing simulations of ITER burn control methods on TRANSP, the PPPL-developed computer code that is used throughout the world to analyze and predict fusion experiments on doughnut-shaped tokamak fusion facilities.  “TRANSP will be a great testbed,” Graber said.

His project will seek to control fusion reactions, which combine light elements in the form of plasma — the state of matter composed of free electrons and atomic nuclei that makes up 99 percent of the visible universe — to generate massive amounts of energy. Researchers around the world are developing science and facilities to reproduce fusion on Earth for a virtually inexhaustible supply of safe and clean power to generate electricity.  

Extend feedback

When Graber arrives at PPPL he plans to extend plasma feedback on TRANSP to include the regulation of burning plasma conditions such as the temperature and density of plasma particles. He next will evaluate the performance of burn control models in TRANSP simulations configured for ITER, and will test models that diagnose the simulated conditions and activate control systems. “By the end of the project we’ll have better judgement of the competence of the controllers we are modeling and testing,” Graber said.

He first became interested in plasma physics during a nuclear engineering course taught by Schuster that he took as an undergraduate. He later became a graduate researcher for the professor and has coauthored papers and poster presentations with him, including a burn control talk last year at the 58th IEEE Conference on Fusion and Control in Nice, France.

Graber’s interest in fusion has continued to grow. He has visited ITER and PPPL and last year attended a plasma physics summer school at the Culham Centre for Fusion Energy in England. His thesis will marry his scholarly interests. “That’s very much so,” he says. “It’s mechanical engineering, it’s control systems, it’s fusion — it’s all three of those things brought together.”

PPPL, on Princeton University's Forrestal Campus in Plainsboro, N.J., is devoted to creating new knowledge about the physics of plasmas — ultra-hot, charged gases — and to developing practical solutions for the creation of fusion energy. The Laboratory is managed by the University for the U.S. Department of Energy’s Office of Science, which is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit