by Chris Peterson » Sun May 17, 2015 5:06 pm
geckzilla wrote:That's a really odd question. We know Chernobyl's fuel melted straight down through concrete, steel, or whatever else was in its way. If it is enough to reach
critcial mass then we get a firework. I kind of imagine it melting into a ball and then the heaviest matter making its way to the center, the fissile material being the heaviest, so an explosion is a good possibility. Prior to reaching criticality, yeah, it would glow. It would never be like Ceres's white spots, though, unless you think, say, snow and glowing hot metal blackbody spectrum are the same.
I doubt it would become critical. Most of the mass of the reactor is non-fissile, and there are materials which are neutron absorbers that would get mixed in. Also, while self gravity would tend to pull the densest stuff towards the center, the force of gravity for such a low total mass would be very small. I think that convection inside the molten, or partially molten zone would dominate and keep things stirred up.
It would glow in the IR, for sure. I don't think that the entire structure would be hot enough to glow visibly, though. In fact, I think most of the structure would remain unmelted, so we'd have surviving structure hiding the actual melted core elements.
[quote="geckzilla"]That's a really odd question. We know Chernobyl's fuel melted straight down through concrete, steel, or whatever else was in its way. If it is enough to reach [url=http://en.wikipedia.org/wiki/Critical_mass]critcial mass[/url] then we get a firework. I kind of imagine it melting into a ball and then the heaviest matter making its way to the center, the fissile material being the heaviest, so an explosion is a good possibility. Prior to reaching criticality, yeah, it would glow. It would never be like Ceres's white spots, though, unless you think, say, snow and glowing hot metal blackbody spectrum are the same.[/quote]
I doubt it would become critical. Most of the mass of the reactor is non-fissile, and there are materials which are neutron absorbers that would get mixed in. Also, while self gravity would tend to pull the densest stuff towards the center, the force of gravity for such a low total mass would be very small. I think that convection inside the molten, or partially molten zone would dominate and keep things stirred up.
It would glow in the IR, for sure. I don't think that the entire structure would be hot enough to glow visibly, though. In fact, I think most of the structure would remain unmelted, so we'd have surviving structure hiding the actual melted core elements.