NERSCPowering Scientific Discovery for 50 Years

Simulation Confirms Method for More Efficient Fusion

Science Highlight

January 29, 2025

By Elizabeth Ball
Contact: cscomms@lbl.gov

inside vessel DIII D

The vessel for a fusion reaction is called a tokamak, like the one at the DIII-D facility in San Diego. (Credit: DIII-D))

Science Breakthrough

With the help of supercomputers at the National Energy Research Scientific Computing Center (NERSC), researchers at the Princeton Plasma Physics Laboratory (PPPL) have confirmed through simulations a method that stops the production of certain unused waves, improving the efficiency of the fusion reaction. Their work was published in the journal Physics of Plasmas.

Science Background

In the process of heating plasma to temperatures required for fusion to occur, a type of wave in the burning plasma known as a slow mode is sometimes produced. These slow modes do not contribute to heating the plasma and are considered wasted energy. But scientists at PPPL were able to find through a series of simulations that placing a metal grate called a Faraday screen at a 5% angle relative to the antenna producing the heating waves (also known as helicon waves) stops the slow modes from forming. In the simulations, the energy that would have gone into the slow modes went instead into heating the plasma, making a more efficient reaction.

Science Breakdown

To run the simulations, the team used NERSC’s current flagship system, Perlmutter, to continue work that started on NERSC’s Cori supercomputer, which has since been retired. The project incorporated full-wave simulations using the Petra-M Finite Element Method (FEM) platform developed by Dr. Syun'ichi Shiraiwa at PPPL. Petra-M efficiently analyzes radio frequency waves—like helicon waves—in both fusion and space plasmas.

Fine-meshed simulations are needed to accurately capture the slow modes. Petra-M's ability to generate non-uniform meshes allowed the researchers to efficiently conduct simulations in both 2D and 3D. They carried out a numerical survey consisting of over 100 different 2D simulations with varying physics parameters.

Research Lead

E.H. Kim

Co-authors

M. Ono, S. Shiraiwa, N. Bertelli, M. Poulos, B. Van Compernolle, A. Bortolon, R. I. Pinsker

Publication

Phys. Plasmas 31, 102102 (2024) https://doi.org/10.1063/5.0222413

Funding

U.S. DOE Office of Science, Office of Advanced Scientific Computing Research, Office of Fusion Energy Sciences


About NERSC and Berkeley Lab
The National Energy Research Scientific Computing Center (NERSC) is a U.S. Department of Energy Office of Science User Facility that serves as the primary high performance computing center for scientific research sponsored by the Office of Science. Located at Lawrence Berkeley National Laboratory, NERSC serves almost 10,000 scientists at national laboratories and universities researching a wide range of problems in climate, fusion energy, materials science, physics, chemistry, computational biology, and other disciplines. Berkeley Lab is a DOE national laboratory located in Berkeley, California. It conducts unclassified scientific research and is managed by the University of California for the U.S. Department of Energy. »Learn more about computing sciences at Berkeley Lab.