Localizing the leak

Honey bees can be trained to sniff out explosives such as TNT, so why not use them for localizing leaks within the ITER vacuum system? Or how about tiny flying robots that take off to explore the intestines of the system? Of course, there are also less fancy but nevertheless very efficient methods such as visible spectroscopy to detect the micron-sized (one millionth of a metre) leak in the system that could shut down the whole machine.

A number of technologies and ideas on how to localize leaks were presented in the recently held brainstorm meeting organized by the ITER Vacuum Group in collaboration with the European Domestic Agency. More than 65 participants from industry and science labs all over the world convened for a three-day "think tank" near Orange, France, to assess what technology exists and what will be required for ITER. "We saw and heard about many very promising technologies," explains Robert Pearce, Vacuum Pumping Section Leader. "But the key issue of ITER is its complexity and restricted accessibility. That makes it different from, and more challenging than, all the working systems we know of today."

The workshop was organized as an intense three-and-a-half day event which alternated between presentations and brainstorming in small working groups. Many of the delegates became so captivated by the issues that some discussions continued until the small hours of the morning. ITER Leak Technical Engineer and Deputy Working Group Chair Liam Worth explains. "The intensive working group format was an excellent way to brainstorm, with the discussions bearing more fruit as the group members began to understand the complexities of ITER systems and the challenge of leak localization."

Soon, the assessment reports from the five working groups will be presented. The next step then will be to define the road ahead, including designs to optimize and technology to investigate further.