In a power reactor the fuel will be operating under very severe conditions. Consequently before a fuel element can be designed it must be tested under conditions which are similar to those in the reactor, and the effect of a large number of variables on the behavior of the fuel must be investigated.
This paper discusses the fuel development program at Chalk River with special reference to the testing of uranium oxide reactor fuels in loops inserted in the NRX reactor. In these loops water may be recirculated over the test elements at temperatures up to 550°F. and pressures up to 2000 psi. The characteristics of a loop are described and the results of various tests are briefly discussed.
The testing of sheathing materials such as Zircaloy-2 and aluminum-nickel alloys is also described.