College of Engineering
University of Wisconsin - Madison
University of Wisconsin Nuclear Reactor Tour
The fuel we use at the UWNR is
Uranium. Our fuel contains Uranium-235
and Uranium-238. Uranium
is mined out of the ground and is about 1% U-235 and 99% U-238. The Uranium
in our fuel is processed and enriched to have a higher concentration
of U-235. Each fuel element is about a meter long, which includes a top and bottom end fitting.
Inside the center of the fuel pin is a mixture of Uranium,
Zirconium, Erbium, and Hydrogen. On either end of this fuel section is a plug of graphite which
helps to reflect neutrons
back toward the fuel, thereby increasing the efficiency of the reactor.
Four of these fuel pins are put together to form a fuel bundle.
A fuel bundle has a square bottom fitting so that it can be positioned in the grid box. It also has a top
fitting which has a handle on it so the bundle can moved around as needed for different tests and experiments.
There are several dozen fuel bundles in the reactor
arranged in a nearly square shaped pattern with the control elemets mized in.
On to the next part of the tour- the control elements.
This is how the fission process works.
Back to the reactor.