Equipped with armor tiles, DIII-D takes “negative triangularity” plasma to new highs

April 26, 2023, 7:00AMNuclear News
A side-by-side comparison of a standard plasma configuration (at left) and the plasma created during the negative triangularity campaign at DIII-D, which was made possible by the installation of a temporary divertor region. (Image: General Atomics)

The DIII-D National Fusion Facility in San Diego, Calif., has completed a monthlong research campaign using a negative triangularity plasma configuration inside its fusion tokamak and produced initial data that “appear very encouraging,” according to an April 24 news release from General Atomics (GA), which operates the Office of Science user facility on behalf of the Department of Energy. Full experimental results on “the highest-powered negative triangularity experiments in the history of the U.S. fusion research program” are expected this summer, according to GA.

Changing things up at the DIII-D National Fusion Facility

July 28, 2022, 12:06PMNuclear News
The new TRFS provides for automated adjustment of the direction of the DIII-D primary magnetic field. (Photos: GA and PPPL)

The DIII-D National Fusion Facility now boasts a unique automated system that allows for a quick reversal of the direction of its magnetic field, expanding the range of possible fusion experiments while reducing downtime. General Atomics, which operates the DIII-D for the Department of Energy’s Office of Science, announced the new Toroidal Field Reversing Switch (TFRS) on July 26.

DIII-D divertor to test tungsten tiles

April 29, 2022, 7:04AMNuclear News
[CLICK to see entire image] Overview of the SAS-VW program at DIII-D. A research concept map illustrates how intense plasma exhaust power entering the divertor leads to the emergence of impurities that can migrate into the plasma core. After identifying the research requirements for the SAS-VW, a process of engineering design, prototyping, and implementation is performed. (Image: General Atomics)

Researchers at the DIII-D National Fusion Facility (DIII-D) are preparing to test a new method that could enable future fusion power plants to withstand the heat and particle flow created by the fusion reaction, General Atomics reported this week.

DIII-D tokamak used to test spacecraft heat shield materials

November 16, 2021, 3:00PMNuclear News
A set of graphite rods was exposed to hot plasma in the DIII-D tokamak. Researchers measured the ablation behavior under extreme heat and particle flow to simulate conditions experienced by spacecraft heat shields during atmospheric entry. (Image: General Atomics)

As a spacecraft on a research mission hurtles at up to 100,000 miles per hour toward the surface of a gas giant like Jupiter, the atmospheric gases surrounding the spacecraft turn to plasma, and spacecraft temperatures increase to more than 10,000 °F.

General Atomics’ compact fusion design shows net-electric potential

April 6, 2021, 12:00PMNuclear News
The outside of the DIII-D tokamak, where testing that supports the development of the Compact Advanced Tokamak has been performed. Photo: General Atomics

Scientists at the DIII-D National Fusion Facility have published research on a compact fusion reactor design they say could be used to develop a pilot-scale fusion power plant. According to General Atomics (GA), which operates DIII-D as a national user facility for the Department of Energy’s Office of Science, the Compact Advanced Tokamak (CAT) concept uses a self-sustaining configuration that can hold energy more efficiently than in typical pulsed configurations, allowing the plant to be built at a reduced scale and cost.

New model stretches the limits of fusion torus control

August 17, 2020, 7:37AMNuclear News

PPPL physicists Raffi Nazikian (left) and Qiming Hu, with a figure from their research. Photo: PPPL/Elle Starkman

Stars contain their plasma with the force of gravity, but here on earth, plasma in fusion tokamaks must be magnetically confined. That confinement is tenuous, because tokamaks are subject to edge localized modes (ELM)—intense bursts of heat and particles that must be controlled to prevent instabilities and damage to the fusion reactor.

Researchers at the Department of Energy’s Princeton Plasma Physics Laboratory (PPPL) and at General Atomics (GA) recently published a paper in Physical Review Letters explaining this tokamak restriction and a potential path to overcome it. They have developed a new model for ELM suppression in the DIII-D National Fusion Facility, which is operated by GA for the DOE. PPPL physicists Qiming Hu and Raffi Nazikian are the lead authors of the paper, which was announced on August 10 by PPPL.