Nuclear explosion in Japan

[AtW]

Someone has written a nicely researched post on HPC

Notice what we saw blowing up on TV (the top bit of the diagram below) is a structure made, at least in part, of blow-out panels. No wonder it looked as if it had been vaporised in the 'blast', it's meant to blow up like that when things start to go a little bit wrong.

Yes, that's a very nice explanation thanks...

But I am still

[TimberWolf]

Do these modern Jap reactors have Boron Balls to drop in case of an emergency if dropping the control rods doesn't stop the reaction, like I think happened at Chernobyl and they didn't have Boron Balls though that's from memory, haven't googled it yet.

I don't think so, it's quite an old design but not the disaster waiting to happen as with Chernobyl:

The RBMK reactor at Chernobyl uses water as a neutron absorber not a moderator. Thus if the coolant water in the reactor boils off, the chain reaction actually speeds up producing more heat and boiling more coolant producing more heat and so on. The BWR design [as used at Fukushima] uses water as a moderator and so with a total loss of coolant, the chain reaction will stop and any subsequent core damage will be contained by the multiple containment layers around the reactor.
Explosion At Fukushima - House Price Crash forum - Page 16

[TimberWolf]

Japan's TEPCO preparing to release radiation from second reactor | Reuters

Maybe vent it outside this time? You're not supposed to blow the bloody reactor doors off. The steam should only contain short lived radioactive nitrogen I believe.

[NickFitz]

Someone has written a nicely researched post on HPC

That is a truly excellent post

Down the pub tonight I drew on it to explain to a number of friends (including a journalist) that it was actually a good thing that the building blew to bits so easily: that way, the force of the explosion was allowed to escape outwards, whereas a stronger structure would have reflected the explosive force back on to the containment vessel of the reactor, which isn't a good thing to do to a reactor containment vessel

It turns out normal people (and even journalists) can understand science and engineering when they're clearly explained

[centurian]

Western style reactors are a negative void co-efficient - in very simple terms this means that constant interaction is required to maintain the nuclear chain reaction. If left alone, the reactor would simply shut down on it's own accord.

Chernobyl was a positive void co-efficient - meaning that it required constant interaction to keep it under control. This meant it could deliver very high power output with quite low grade of uranium. You don't need to be a genuis to work out the disadvantages of this design - even before 1986

[centurian]

Explosion At Fukushima - House Price Crash forum - Page 16

I was going to ask "So as a Daily Mail reader, what does this mean for house prices", but I see it's already being discussed.

[centurian]

Sky News is reporting that the danger is not over yet - in fact it is escaling. One reactor is starting to melt down

[Pogle]

Sky News is reporting that the danger is not over yet - in fact it is escaling. One reactor is starting to melt down

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[centurian]

Clearly the meaning is Japanese is different, but calling a nuclear power plant Fuku....

[suityou01]

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