Enviro Tech Aug 10 2016
A major breakthrough from a team of scientists at the Massachusetts Institute of Technology (MIT) might just have opened the door to a clean, almost endless supply of energy to solve our current crisis. By using sophisticated computer technology, the researchers were able to create a model of conditions inside the fusion reactor and analyse why the operation was stalling.
Though overcoming all of the obstacles to mastering this incredible source of energy is far from complete, we are now one step closer to understanding exactly how the process works and achieving a self-sustaining nuclear fusion which can provide enough power for us all.
We need to talk about fusion
At a fundamental level, nuclear fusion is brought about by subjecting heavy hydrogen atoms (known as deuterium) to intense levels of heat and pressure. This in turn makes them overcome their natural resistance to one another and stick together, forming helium, at which point fusion has occurred and immense amounts of energy are released.
However, scientists have had real trouble in maintaining these high temperatures. Turbulence occurs inside the plasma reactor for unknown reasons, causing the temperature to fluctuate unpredictably. This not only breaks the fusion process due to the falling thermostat, but also raises potential safety concerns, since we are effectively unable to predict how the turbulence will behave.
A ground-breaking discovery
Earlier this year, a team of scientists at MIT’s Plasma Science and Fusion Centre worked in collaboration with others from Princeton and the University of California (UCAL) San Diego to assess what might be causing the turbulence. Previously, it had been assumed that turbulence caused by ions would obliterate smaller disturbances among electrons, since the latter are almost two orders of magnitude tinier.
However, this conventional wisdom was thrown out of the window when it was realised that not only did the larger turbulence not completely absorb the smaller turbulence, but that the two were intrinsically linked and interacted with each other in ways scientists had never previously before imagined possible.
In order to investigate these interactions further, the team had to run an extensive computer model incorporating turbulence both on the ion and electron scale. Since they are so far apart, an incredible amount of processing time was needed to run through all possible scenarios. In fact, each simulation demanded around 15 million hours of computer processing time, which was executed over a 37-day period using 17,000 processors. To give you an idea of perspective, the same job being carried out on an everyday MacBook would have taken the best part of 3,000 years.
The next step
Now that scientists are aware that electron-scale turbulence is not wiped out by its bigger brother, they can factor it into their research more effectively. Previously, researchers had attempted to cut down on computer processing time by simply running two separate models (one for ion, one for electron) and compiling the results.
However, the new breakthrough demonstrates that such an approach yields inaccurate results, and that by creating a faster, more streamlined software package capable of analysing both turbulence streams on the same model, we can gain a better insight as to how nuclear fusion works.
Armed with this knowledge, scientists hope to be able to work to combat the turbulence (or at least channel it to minimalize its impact on plasma temperatures), thus paving the way for nuclear fusion as a viable energy source. At a moment when the renewable energy economy is thriving, such a breakthrough couldn’t be more conveniently timed.
Image Source: Matthias Weinberger