Facing Plasma's Challenge
Deep in the French countryside northeast of idyllic Marseilles, an international team of scientists are cooking up something big. Construction will begin in 2009 in Cadarache on the 15-story, $15 billion ITER, the International Thermonuclear Experimental Reactor. ITER, which means “the way” in Latin, promises to demonstrate the scientific and technological feasibility of fusion energy for peaceful purposes. “This is the most complex technology made by man,” says Purdue’s Jeffrey Brooks, a research professor in the School of Nuclear Engineering, “and it’s also one of the most important.”
Brooks is into important projects. Not content merely to go about replicating the energy of stars to help solve the global energy crisis, Brooks is also involved in numerous other areas. He works on national defense projects; he consults on fluid dynamics models to numerically simulate blood flow in the heart and coronary arteries to predict where life-threatening clots will form; and he creates software to simulate complex physical processes such as those used by the semi-conductor industry, which uses plasmas in microchip production. “I try to identify what I think are the key questions,” says Brooks, who admits that his hunger for challenge seems to stem from the simple fact that he “gets bored easily.”
Brooks’ job on the ITER project is anything but boring. He must figure out the right recipe for the material inside the fusion reactor. “Designing the plasma-facing surfaces of the reactor remains one of the biggest challenges in developing reliable nuclear fusion,” says Brooks. The plasma is confined by magnetic fields, but it interacts with the surfaces it touches. Such contact can be harmful both to the walls, which are subject to erosion from intense local heating, and to the plasma, which is easily contaminated and cooled—“put out”—by impurities. The trick for Brooks as the chair of the Department of Energy’s Plasma-Facing Component Systems Group will be to determine the best design for a surface material that can stand up to these forces and protect the plasma so it can one day be harnessed to produce energy.
A new proposal is in the works for Brooks and his friend and colleague Ahmed Hassanein, a professor of nuclear engineering, whom he met at the Argonne National Laboratory. Together they hope to work out mathematical models on super computers that will help focus ITER research. An ITER experiment will cost about $1 million per “plasma shot.” In a shot, the plasma is turned on for 400-1,000 seconds. By applying data gleaned from computer simulations, Brooks and Hassanein have an opportunity to “optimize the shot,” that is, guide the parameters of the experiment to maximize the experiment time and cost.
And timing is everything. ITER is slated to be up and running by 2016, a very tight window by all accounts. Finely tuned experimentation will help push the theoretical goal towards the technological realization.
The promise of fusion energy is tantalizing to scientists like Brooks. “If fusion works, the impact will be fantastic,” he says. “The fuel mostly comes from water, the fuel is essentially free, and the possibility exists for an unlimited source of energy. It would be an extremely important addition to the world’s energy portfolio.”
He also points out that a fusion reaction is inherently safe; it cannot meltdown. Further, very little long-term nuclear waste is produced, and no carbon dioxide or greenhouse gases are released during the reaction. Clean, safe, limitless energy will not come easily, though. “Fusion presents some of the most technologically advanced challenges,” Brooks says, “but it promises the highest payoff.” And that’s just the kind of job Brooks likes best.
- Gina Vozenilek