Quote:
Originally Posted by 'Hamas' Jenkins
I'd actually be more interested to know about the engineering challenges facing the reactors.
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I really can't speak to ITER as much as I can NIF. With NIF you have a hohlraum, which is basically a little metal cylinder that holds the fuel you plan to fuse.
NIF has 192 lasers that they fire simultaneously at the hohlraum which are supposed to create the necessary heat and pressure to cause ignition. The problem so far has been that the compression hasn't been even... and it has to be. There are two ways to address the issue. 1)you mess with the hohlraum 2)you mess with the lasers. There are quite a few who think it's simply a question of increasing the laser output which is of course easier said than done.
They were making gains on these fronts when Congress and Obama decided to redirect their resources and scale back the project. They are still moving forward but at a much slower rate.
The most frustrating thing about NIF is that everyone agrees that it SHOULD work right now. They have met the requirements that everything we know to create the computer models say we need to meet. As with anything like this it may never work, BUT they are so close "in theory" that they could try one thing and get ignition tomorrow. Of course they get fewer and fewer chances to try different things with less and less funding.
Ok that was a very simplified version of the main issues they face at NIF. NIF is a mix of engineering issues (increasing the laser power, hohlraum shape, size, material, etc) and the fundamental physics issue of why it doesn't work now when the models say it should.
It;s important to remember that NIF is BRAND NEW and already people are giving up on it. The facility was supposed to achieve ignition in September of 2012. They are only what, 8 months behind?
Fun fact for those who have seen the new Star Trek movie... the warp core in the movie... that's NIF! (well parts of it at least)
