US scientist proposes ‘tungsten shotgun’ to enhance fusion reactor stability
Given its exceptional strength and resilience to extremely high temperatures, tungsten already plays a crucial role in the construction of fusion reactor walls.
Researchers at Los Alamos National Laboratory (LANL) are exploring a novel approach to mitigate a critical challenge in fusion energy development, i.e., the detrimental effects of runaway electrons. Electron runaway arises from plasma instabilities within fusion reactors.
“Fusion reactors work by extracting tremendous sums of energy from the fusion of lighter atomic nuclei into a heavier nucleus,” said LANL in a press release.
To achieve this, scientists need to create a superheated plasma, a state of matter where electrons are stripped from atoms, reaching temperatures exceeding 150 million degrees Celsius.
“But instability breeds in extreme conditions. The plasma is wildly unruly and often tries to escape the reactor,” highlighted the press release.
“One severe byproduct of this instability is runaway electrons.”
‘Tungsten shotgun’ for runaway electrons
These electrons, accelerated to near-light speed, can escape the magnetic fields designed to contain them and collide with the reactor walls.
These collisions can cause significant damage, potentially leading to costly repairs and operational downtime.
“It isn’t damage over time. In one event, the beam can punch a hole in a solid tungsten wall, damaging the subsurface cooling mechanism beneath,” remarked Michael Lively, a fusion expert at Los Alamos, who has proposed a solution to this issue.
Lively suggests the implementation of a “tungsten shotgun.”