Abstract
Unsteady flow loading of fuel assemblies in Pressurised Water Reactors power plants is a potential cause of deformation and of fretting wear damage. Inside a fuel assembly, rods are arranged in 17 x 17 bundles. The rod diameter is equal to about 9 mm, and the gap between two rods is equal to about 2 mm. Each rod is several meters long, and mixing grids are arranged every 0.4 m. The axial flow velocity is equal to about 5 m/s, so that the Reynolds number reaches 5 x 105 in the reactor configuration. Due to the complexity of the turbulent flow pattern, an accurate description of the fluid-structure interaction is still a challenging task, and only a few data about this issue are available today in literature. Recent Computational Fluid Dynamics results are revisited from the point of view of classical axial turbulence-induced vibrations. The unsteady pressure force Power Spectral Densities are determined, a convective velocity is derived, and an estimation of the axial correlation length for the pressure force is given. The results agree reasonably well with the scientific literature.
| Original language | English |
|---|---|
| Pages (from-to) | 251-259 |
| Number of pages | 9 |
| Journal | American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP |
| Volume | 4 |
| DOIs | |
| Publication status | Published - 1 Dec 2011 |
| Externally published | Yes |
| Event | ASME 2011 Pressure Vessels and Piping Conference, PVP 2011 - Baltimore, MD, United States Duration: 17 Jul 2011 → 21 Jul 2011 |