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Name: Unknown
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993

Texts say Chernobyl was a high-pressure water reactor, navy nuclear expert says it used sodium. Does anybody know and can suggest references?

Here are the facts. The RBMK-1000 is water cooled. The water is under pressure. The moderator was graphite which did not have a separate cooling system so when the primary cooling system (the only one) was shut down, the moderator got very hot and being graphite could actually burn in oxygen. It contained 115 Kg of uranium in fuel assemblies that each contained 18, 13.6mm diameter rods of Uranium. The water was not deuterium oxide, but regular water. The confinement system was not complete and that is why it went up. We have a lecture that was given here at Argonne by a safety engineer and if you are interested we could send you a copy. It is very technical. IF you would write a letter to S. Bowen, DEP, ANL, Argonne, IL 60439, I would pass the request for references on to our local expert. The moderator is graphite. You are right. The collisions are to be elastic. There are some small inelastic energy transfers to vibrations in the moderator. In practice there will be both types of collisions with the moderator. The inelastic collisions will cool the neutrons and the elastic will rearrange the momentum distributions.

Sam Bowen

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