Effects of plate curvature on thermo-mechanical performance of U-10Mo monolithic fuel plates

Abstract

Monolithic fuel is a candidate fuel form being considered for the conversion of high-performance research reactors. This plate-type fuel consists of a high-density, U-Mo fuel in a monolithic form that is sandwiched between zirconium diffusion barriers, and encapsulated in an aluminum cladding. To date, large number of plates have been irradiated with satisfactory performance. The program is now moving into the qualification phase, a predecessor to the timely conversion of the target reactors. Since each reactor employs distinct fuel plate geometries for various consideration, resulting nearly 50 distinct plate geometries with unique plate design features, a single “generic” plate geometry capturing all of the extremities is not achievable. This limitation consequently requires much more cautious performance evaluations, as thermal and mechanical response of a plate with certain geometry may not be representative for a plate with a different geometry. To evaluate the performance of the plates for various geometric parameters, parametric sensitives studies have been employed. One of the important geometric parameters may have potential effects on the performance is the plate curvature. In this study, curved-plates were parametrically simulated to investigate if this geometric parameter has any effects on overall performance, In particular, radius of curvatures of the plates were varied between the bounding values, and the plates were simulated for comparable irradiation histories. The resulted temperature, deformation, stress-strain results were comparatively evaluated. The results have indicated that preferential deformations occur. This consequently caused shifting of plate centerline on curved plates. The magnitude of centerline shifts increased with increasing plate curvatures.