Cant a power down of japans nuclear power plants prevent the meltdown?

Franklin

I'm not totally sure of how these things work, but a meltdown is a result of an overheating reactor right? So if there is no coolant/water to cool the reactor, wouldn't stopping the reaction completely stop producing the heat without further cooling needed?



Cassville

No - the process of nuclear fission is self-sustaining. Without coolant, the core just generates more and more heat as the atoms split and cause other atoms to split as well, and the rate in which the atoms fissure will simply rise. The increasing number of reactions generates heat, and more heat causes the normally-solid fuel rods to melt.



Pennsauken

latent heat is caused by the decay of daughter particles from the primary reactions in the power plant.. the longer the plant has been operating the more daughter products there are.. the longer it generates latent heat. japan has been running those reactors for close to 40 years. the heat will continue to build up and the primary containment will fail if they can't provide cooling... however as long as secondary and tertiary containment holds all you will end up with is a building you can't enter



Salem

Rods holding nuclear materials are becoming exposed. Once they reach a certain degree, they melt & explosions result. Sea water is being pumped in but it may be too late. Powering down helps nothing. Such a reaction has a life of ITS OWN.