Fretting wear behaviors of a dual-cooled nuclear fuel rod under a simulated rod vibration

摘要: Recently, a dual-cooled fuel (i.e., annular fuel) that is compatible with current operating PWR plants has been proposed in order to realize both considerable amount of power uprating and an increase safety margins. As the design concept should be plants, however, it shows narrow gap between rods when compared solid nuclear arrays needs modify spacer grid shapes their positions. In this study, fretting wear tests have performed evaluate resistance by using spring dimple grids cantilever type hemispherical shape, respectively. result, volume specimen gradually increases as contact condition changed from certain gap, just positive force. However, specimen, large volume. addition, circular rod motion at upper region surface increased its diametric size depends on depth increase. Based test results, analyzed comparing measurement results detail.