Testing of research reactor fuel in the high flux reactor (Petten)

The two types of fuel most frequently used by the main research reactors are metallic : highly enriched uranium (>90%) and silicide low enriched uranium (<20%) at 4,8 g/cm(3). However, a need exists for research on new reactor fuel. This would permit some plants to convert without losses in flux or in cycle length and would allow new reactor projects to achieve higher possibilities especially in fluxes. In these cases research is made either on silicide with higher density, or on other types of fuel (UMo, etc.). In all cases when new fuel is proposed, there is a need, for safety reasons, to test it, especially regarding the mechanical evolution due to burn-up (swelling, etc.). Initially, such tests are often made with separate plates, but lately, using entire elements. Destructive examinations are often necessary. For this type of test, the High Flux Reactor, located in Petten (The Netherlands) has many specific advantages : a large core, providing a variety of interesting positions with high fluence rate a downward coolant flow simplifies the engineering of the device there exists easy access with all handling possibilities to the hot-cells the high number of operating days (>280 days/year), together with the high flux, gives a possibility to reach quickly the high burn-up needs an experienced engineering department capable of translating specific requirements to tailor-made experimental devices a well equipped hot-cell laboratory an site to perform all necessary measurements (swelling, gamma-scanning, profilometry) and all destructive examinations. In conclusion, the HFR reactor readily permits experimental research on specific fuels used for research reactors with all the necessary facilities on the Petten site.