Here’s what you’ll learn when you read this story:
- A fusion reactor could be a source of virtually endless energy, but it’s difficult to track critical particle collisions.
- Scientists in South Korea created a virtual model of their reactor that uses an algorithm meant for a video game to track collisions.
- The video game-boosted digital reactor performed so well it could lead to great improvements in reactor technology.
A fusion reactor’s main job is smashing subatomic particles together in a searing hot, high-energy plasma cloud.
The main event of most tokamaks—toroidal-shaped fusion reactors—is the collision and fusing of the heavy isotopes of hydrogen, called deuterium and tritium. But that’s only one important collision that needs to take place in these reactors, such as the International Thermonuclear Experiment Reactor (ITER) currently being built in southern France. Another type of collision involves “fast ions,” which carry the lion’s share of the plasma’s kinetic energy as they slam into bulk ions, which make up the main bulk of the plasma. This collision is what keeps the plasma hot enough for any fusion reaction to occur in the first place. In other words, these collisions are the whole ballgame. Yet, keeping track of them, especially in the chaotic environment of a fusion reactor, is enormously difficult.
A promising method is to make a digital recreation—and researchers in South Korea recently found inspiration in video games. It turns out that the most accurate visualization of ultrafast ion collisions in a 3D digital space comes from a video game algorithm.
Scientists from Ulsan National Institute of Science and Technology in Korea (UNIST) decided to track these collisions in a more hospitable environment than an actual tokamak. Known as a “digital twin” of the Korea Superconducting Tokamak Advanced Research (KSTAR), it’s an engineering technique that creates a digital copy of a physical device, so scientists can experiment more rapidly and still get accurate results. Virtual KSTAR, or V-KSTAR, creates a unified framework that integrates machine and fusion data, providing a necessary step between lab-based reactors and commercial fusion.
For years UNIST and the Korea Institute of Fusion Energy (KFE) have been perfecting a digital twin of KSTAR—one of the premiere fusion reactors in the world. In 2024, the reactor broke records by sustaining a high-temperature plasma for 48 seconds at 100 degrees Celsius. While other reactors, particularly the WEST reactor in France and EAST reactor in China, have maintained plasmas for upwards of 22 minutes, neither have reached temperatures hot enough for a fusion reaction to take place.
To improve that impressive fusion record, scientists developed an accurate digital recreation using Unity, a popular video game engine that’s been available for more than 20 years. In a new paper published in the journal Computer Physics Communications, scientists detail using use a specific video game tool that typically detects a bullet hitting a virtual target. Instead, they used the tool to detect fast ion collisions. Previously, this detection process required constant calculations to track 300,000 particles as they slammed into the 70,000 wall triangles making up the collision area. The authors estimate that the video game-boosted algorithm could increase fusion reactor analysis by a factor of 15, while reducing 99.9 percent of those calculations. That’s because the algorithm only activates when a collision is likely.
Accuracy and efficiency are particularly essential for keeping tabs on a plasma heating method known as neutral beam injection. This method injects high-energy particles into the plasma that cause collisions and helps keep the plasma many times hotter than the core of the sun. However, those particles can sometimes smack into the reactor wall, which can significantly impact the fusion process.
“Our algorithm has enabled KFE to enhance its neutral particle beam simulator by extending it into a three-dimensional [virtual] framework,” UNIST’s Eisung Yoon, Ph.D., the senior author of the new study, said in a press statement. “This advancement allows for improved visualization of light path distributions in optical diagnostic equipment and supports the analysis of magnetic field perturbations [which can alert researchers to plasma imbalances].”
V-KSTAR isn’t just some kind of hyper-accurate video game called Fusion Reactor Simulator (though honestly I would play it). As fusion reactors evolve from the experimental to the everyday, these virtual reactors—especially when they integrate with artificial intelligence and machine learning—will become an invaluable diagnostic tool.
For the fusion dream to become a physical reality, we may first need to play with virtual fusion reactors—and that’s where video games reign supreme.
Darren lives in Portland, has a cat, and writes/edits about sci-fi and how our world works. You can find his previous stuff at Gizmodo and Paste if you look hard enough.
