Chernobyl, blamed on operators (which may be true) also had a seismic "anomaly beforehand. They were unable to lower the rods to safety. Think of the effect of gradual beta decay directly over an operating reactor, warping the control rods/covers preventing proper SCRAM. http://www.rri.kyoto-u.ac.jp/NSRG/reports/kr139/pdf/karpan.pdf
On Fri, Nov 23, 2012 at 12:46 PM, Jed Rothwell <[email protected]>wrote: > Vorl Bek <[email protected]> wrote: > > > >> I thought that reactors were designed so that inserting rods of >> some material would kill the reaction. I imagine they would have >> battery power for long enough to insert the rods; heck, maybe >> they even have a manual way to crank the motor to do it. >> > > They can all be gravity actuated as far as I know. The rods are above, and > they fall straight down into the reactor core. That is called a reactor > SCRAM. It does stop the reaction. Every reactor undergoes an emergency > SCRAM from time to time, usually in response to a stuck valve or a clogged > pipe. The Three Mile Island reactor accident began with a SCRAM from > clogged pipe. Fukushima was scrammed in the first seconds of the > earthquake. However, that is not enough to prevent a catastrophe. At > Fukushima the tsunami destroyed their generator capacity, and cut their > connection to the network, which led to the destruction of the reactors and > the hydrogen explosions. > > - Jed > >
