by DoctorDoom » Sat 21 Aug 2004, 16:12:01
It did indeed, thanks for posting it. Skeptics, don't laugh, you really can get fusion to occur using vacuum tube technology. In fact there was an article about this in a science magazine just a few years ago, with plans sufficiently detailed that someone could (and, I believe, did) build a device as a science fair project. The device is about the size of Mr. Fusion from "Back to the Future" - it looks like a coffee-maker-sized tube of thick glass with a wire mesh ball mounted on a pedastal in the center, and some other wires inside it. My vague recollection is that the electric field starts deuterium ions moving in a path that goes straight into the center of the device and back out the other side (because the "ball" attracting them is made of a mesh, so most of them don't hit anything). They go back and forth like this from all sides, in a roughly spherical pattern, the idea being that the odds of a sufficiently energetic collision are higher in the center than they'd be if the ions moved around at random.
There's a catch, of course - very little fusion actually occurs. Only very high-energy ions colliding virtually head-on will fuse. So little fusion occurs that there's no radiation danger at all, and in fact you'd need very sensitive instruments to even measure that things are working. A lot more energy goes into the device than you could possibly extract. I have the magazine, I just wish I could find an on-line reference to it. It's way cool to think you can build a fusion reactor at home, even if it's not a practical energy source!