Interlocks

Over the past week or so I've been working on some of the electrical aspects of our experiment. We've decided that instead of having different components run at different voltages, we're going to run all of it at high voltage (around 30,000V). We decided to do this because if you've got one component running at high voltage and another at a much lower voltage, the possibility of a discharge between the two is much higher. Also, if such a discharge were to occur, it could be very dangerous. Ohm's law states that voltage is proportional to current via a constant, resistance. Hence, V = I*R. Assuming a constant resistance, the higher the voltage difference between to points, the higher the current between them. Air is actually a wonderful insulator, but it's just safer (and easier) to hold everything at high voltage.

There is still danger, though. You don't want people running around the the high voltage area while it's running, so we're having to design an interlock and grounding hook system (I think I mentioned this a few posts back? Now for more details!). The power supplies we use have two jumper screws on the back of them. Normally, there's a small wire that connects the two. If they are connected, then the power supply runs. If they're disconnected, it won't turn on. We're going to have a large cage built around the high voltage components and have a system such that if you open one of the three doors a switch will open, which opens the circuit between the jumper screws, and will shut off the high voltage power supply. Essentially, this is three switches in series that are normally closed when the doors are closed.

We've also got to have a way to discharge any latent charge in the components. Enter the grounding hooks! Each door will have a fiberglass rod with a metal hook running through it blocking the door during operation. Each rod is independently connected to a common ground (zero voltage). To enter the room, a door must be opened. Then, the hook has to be removed and then hooked onto a predesignated spot that will discharge any latent charge in the system. Voila! Safety!

I think I've found what I want to do research on during my Ph.D. Dr. Carter is trying to get a collaborative program between Nuclear Engineers and Nuclear Physicists started here at the lab. He wants to do decay heat measurements relevant to nuclear reactors. When a radioactive element decays from one species to the next, there is a significant release of energy (the decay heat). This energy is what's used to power nuclear reactors. Having a better understanding of all the different decay processes will allow better control of those processes which, in turn, allow for more efficient reactors. I talked to a guy at UT who will be working on this project once funding comes in and he was really excited about my background at Tech in physics. He was also excited to hear that I was working on the helium jet. What's awesome is that if I decide to work with this guy I could be using the same helium jet that I helped develop!

There's a problem, though: funding. The group may have funding come September, but there's no guarantee. If there's no funding, then I can't be hired. If I can't get hired, then my tuition isn't waived (which is stupid expensive, being an out of state student). This isn't all bad, though, since I've been told that funding will almost certainly happen... they're just not sure when. I've been assured that I'll have a job here at the lab until the end of the year. I may just have to wait until Spring to start classes if funding comes a little late. No big deal, but I'd rather start sooner than later.

I'm also talking to a few other professors about their research. One guy does measurements pertaining to space radiation protection as well as developing materials that will protect astronauts from this radiation. Another guy does research in nuclear non-proliferation, which essentially means keeping dangerous nuclear technology out of the wrong hands. All three professors are essentially doing applied nuclear physics research and tip-toe the line between nuclear engineering and physics. This just so happens to be the exact sort of thing I'd like to do!

A bunch of Psi U's are going on a cabin trip in the Blue Ridge mountains this weekend and I'm super pumped! It's supposed to be warm and sunny until late Sunday, so plenty of awesome nature things to see.