In the relentless pursuit of clean, sustainable energy, scientists are continually pushing the boundaries of fusion research. Recent findings from the Experimental Advanced Superconducting Tokamak (EAST) in China have shed new light on the intricate dance between edge-localized modes (ELMs) and internal transport barriers (ITBs) in plasma, a phenomenon that could significantly impact the future of fusion energy.
Dr. X. Gao, a researcher at the Institute of Plasma Physics, Chinese Academy of Sciences, led a study that delves into the behavior of ELMs and their penetration into ITB plasmas. The research, published in the journal “Nuclear Fusion” (translated to English), reveals that when ELMs penetrate deeply into the plasma, they can cause the ITB to shrink or even collapse.
The EAST tokamak, with its flat central safety factor profile, provided an ideal setting for this study. “We observed that when the ELM inward penetration radius reaches the ITB foot region, it has a significant influence on the ITB plasma,” Dr. Gao explained. This influence can lead to the collapse of the ITB, a critical component in maintaining the stability and efficiency of fusion reactions.
The study found that large ELM penetrations can trigger off-axis sawtooth events, which further decrease the core stored energy. The reversal surface of these off-axis sawteeth is situated around the ITB foot, and the delay between ELM penetration and ITB collapse is about 2–3 milliseconds. “The expanding of ITB is related to the net heating power,” Dr. Gao added, highlighting the complex interplay between various factors in fusion plasmas.
Understanding these dynamics is crucial for the development of commercial fusion reactors. ELMs, while natural occurrences in tokamak plasmas, can pose significant challenges to the integrity of the reactor walls. By gaining insights into how ELMs interact with ITBs, scientists can develop strategies to mitigate their impact and enhance the stability of fusion reactions.
The findings from Dr. Gao’s research could shape future developments in the field, paving the way for more stable and efficient fusion reactors. As the world looks to fusion energy as a potential solution to its energy needs, such advancements bring us one step closer to a sustainable energy future.
The study, “ELM penetration in ITB plasma on EAST tokamak,” offers a deeper understanding of the complex behaviors within fusion plasmas. As Dr. Gao and his team continue to unravel these mysteries, the energy sector watches closely, eager to harness the power of fusion for a cleaner, brighter tomorrow.