A breakthrough in fusion research has led to a significant improvement in plasma heating efficiency, thanks to the strategic placement of metal screens. Researchers at the US Department of Energy’s Princeton Plasma Physics Laboratory (PPPL) have developed a technique that prevents the production of unwanted waves, known as slow modes, which can waste energy and hinder the fusion process.
The team used 2D computer simulations to explore how to reduce slow modes in plasma devices. They discovered that positioning a Faraday screen at a slight five-degree slant with respect to the antenna producing heating waves stops the production of slow modes. This design tweak boosts the heat put into the plasma, increasing the efficiency of fusion reactions.
The researchers simulated various conditions, including different antenna alignments and Faraday screen angles. Their findings showed that when the Faraday screen is aligned at an angle of five degrees or less from the antenna’s orientation, it effectively short-circuits slow modes, making them dissipate before they can propagate into the plasma.
The suppression of slow modes depends on the Faraday screen’s alignment, with even small deviations causing a significant increase in slow mode growth. This knowledge can be used to optimize the design of new fusion facilities, making their heating more powerful and efficient. Future research plans include running simulations that consider more of the plasma’s properties and factor in additional information about the antenna to further improve slow mode suppression.
This breakthrough has the potential to lead to more efficient plasma heating and an easier path to fusion energy, a goal that has been pursued by scientists for decades.
Source: https://phys.org/news/2024-12-plasma-efficiency-fusion-devices-boosted.html